Chapter 1. Using the Command-Line Interface

Information About Using the Command-Line Interface

Command Modes

Understanding Abbreviated Commands

No and Default Forms of Commands

CLI Error Messages

Configuration Logging

Using the Help System

Configuring the Command History

Changing the Command History Buffer Size

Recalling Commands

Disabling the Command History Feature

Enabling and Disabling Editing Features

Editing Commands Through Keystrokes

Editing Command Lines That Wrap

Searching and Filtering Output of show and more Commands

Accessing the CLI on a Switch Stack

Accessing the CLI Through a Console Connection or Through Telnet

Chapter 2. Using the Web Graphical User Interface

Prerequisites for Using the Web GUI

Information About Using The Web GUI

Web GUI Features

Connecting the Console Port of the Switch

Logging On to the Web GUI

Enabling Web and Secure Web Modes

Configuring the Switch Web GUI

Chapter 3. Configuring Interface Characteristics

Finding Feature Information

Information About Configuring Interface Characteristics

Interface Types

Port-Based VLANs

Switch Ports

Access Ports

Trunk Ports

Tunnel Ports

Routed Ports

Switch Virtual Interfaces

SVI Autostate Exclude

EtherChannel Port Groups

10-Gigabit Ethernet Interfaces

Power over Ethernet Ports

Using the Switch USB Ports

USB Mini-Type B Console Port

Console Port Change Logs

USB Type A Port

Interface Connections

Interface Configuration Mode

Default Ethernet Interface Configuration

Interface Speed and Duplex Mode

Speed and Duplex Configuration Guidelines

IEEE 802.3x Flow Control

Layer 3 Interfaces

How to Configure Interface Characteristics

Configuring Interfaces

Adding a Description for an Interface

Configuring a Range of Interfaces

Configuring and Using Interface Range Macros

Configuring Ethernet Interfaces

Setting the Interface Speed and Duplex Parameters

Configuring IEEE 802.3x Flow Control

Configuring Layer 3 Interfaces

Configuring SVI Autostate Exclude

Shutting Down and Restarting the Interface

Configuring the Console Media Type

Configuring the USB Inactivity Timeout

Monitoring Interface Characteristics

Monitoring Interface Status

Clearing and Resetting Interfaces and Counters

Configuration Examples for Interface Characteristics

Adding a Description to an Interface: Example

Configuring a Range of Interfaces: Examples

Configuring and Using Interface Range Macros: Examples

Setting Interface Speed and Duplex Mode: Example

Configuring Layer 3 Interfaces: Example

Configuring the Console Media Type: Example

Configuring the USB Inactivity Timeout: Example

Additional References for the Interface Characteristics Feature

Feature History and Information for Configuring Interface Characteristics

Chapter 4. Configuring Auto-MDIX

Prerequisites for Auto-MDIX

Restrictions for Auto-MDIX

Information about Configuring Auto-MDIX

Auto-MDIX on an Interface

How to Configure Auto-MDIX

Configuring Auto-MDIX on an Interface

Example for Configuring Auto-MDIX

Additional References

Feature History and Information for Auto-MDIX

Chapter 5. Configuring Ethernet Management Port

Finding Feature Information

Prerequisites for Ethernet Management Ports

Information about the Ethernet Management Port

Ethernet Management Port Direct Connection to a Switch

Ethernet Management Port Connection to Stack Switches using a Hub

Ethernet Management Port and Routing

Supported Features on the Ethernet Management Port

How to Configure the Ethernet Management Port

Disabling and Enabling the Ethernet Management Port

Additional References

Feature Information for Ethernet Management Ports

Chapter 6. Configuring LLDP, LLDP-MED, and Wired Location Service

Finding Feature Information

LLDP, LLDP-MED, and Wired Location Service Overview

LLDP

LLDP Supported TLVs

LLDP and Cisco Switch Stacks

LLDP and Cisco Medianet

LLDP-MED

LLDP-MED Supported TLVs

Wired Location Service

Default LLDP Configuration

Restrictions for LLDP

How to Configure LLDP, LLDP-MED, and Wired Location Service

Enabling LLDP

Configuring LLDP Characteristics

Configuring LLDP-MED TLVs

Configuring Network-Policy TLV

Configuring Location TLV and Wired Location Service

Enabling Wired Location Service on the Switch

Configuration Examples for LLDP, LLDP-MED, and Wired Location Service

Configuring Network-Policy TLV: Examples

Monitoring and Maintaining LLDP, LLDP-MED, and Wired Location Service

Additional References for LLDP, LLDP-MED, and Wired Location Service

Feature Information for LLDP, LLDP-MED, and Wired Location Service

Chapter 7. Configuring System MTU

Finding Feature Information

Information about the MTU

Restrictions for System MTU

System MTU Value Application

How to Configure MTU Sizes

Configuring the System MTU

Configuring Protocol-Specific MTU

Configuration Examples for System MTU

Additional References for System MTU

Feature Information for System MTU

Chapter 8. Configuring Internal Power Supplies

Information About Internal Power Supplies

How to Configure Internal Power Supplies

Configuring Internal Power Supply

Monitoring Internal Power Supplies

Configuration Examples for Internal Power Supplies

Additional References

Feature History and Information for Internal Power Supplies

Chapter 9. Configuring Stack Power

Finding Feature Information

Prerequisites for StackPower

Information About StackPower

Power Supplies for the Stacking Switch

StackPower Modes

Power Priority

Load Shedding

How to Configure StackPower

Configuring PowerStack Parameters

Configuring PowerStack Switch Power Parameters

Configuring PoE Port Priority

Configuration Examples for Stack Power

Immediate Load Shedding: Examples

Configuring PowerStack Parameters: Example

Configuring PowerStack Switch Power Parameters: Example

Configuring PoE Port Priority: Example

Where to Go Next

Additional References for StackPower

Feature History and Information for StackPower

Chapter 10. Configuring PoE

Finding Feature Information

Information about PoE

Power over Ethernet Ports

Supported Protocols and Standards

Powered-Device Detection and Initial Power Allocation

Power Management Modes

Power Monitoring and Power Policing

Power Consumption Values

Cisco Universal Power Over Ethernet

How to Configure PoE

Configuring a Power Management Mode on a PoE Port

Enabling Power on Signal/Spare Pairs

Configuring Power Policing

Monitoring Power Status

Additional References

Feature Information for PoE

Chapter 11. Configuring EEE

Finding Feature Information

Information About EEE

EEE Overview

Default EEE Configuration

Restrictions for EEE

How to Configure EEE

Enabling or Disabling EEE

Monitoring EEE

Configuration Examples for Configuring EEE

Additional References

Feature History and Information for Configuring EEE

Preface

Document Conventions

Related Documentation

Obtaining Documentation and Submitting a Service Request

Copyright Page

Chapter 1. Using the Command-Line Interface

- Information About Using the Command-Line Interface

Information About Using the Command-Line Interface

- Command Modes

- Understanding Abbreviated Commands

- No and Default Forms of Commands

- CLI Error Messages

- Configuration Logging

- Using the Help System

Command Modes

The Cisco IOS user interface is divided into many different modes. The commands available to you depend on which mode you are currently in. Enter a question mark (?) at the system prompt to obtain a list of commands available for each command mode.

You can start a CLI session through a console connection, through Telnet, an SSH, or by using the browser.

When you start a session, you begin in user mode, often called user EXEC mode. Only a limited subset of the commands are available in user EXEC mode. For example, most of the user EXEC commands are one-time commands, such as show commands, which show the current configuration status, and clear commands, which clear counters or interfaces. The user EXEC commands are not saved when the switch reboots.

To have access to all commands, you must enter privileged EXEC mode. Normally, you must enter a password to enter privileged EXEC mode. From this mode, you can enter any privileged EXEC command or enter global configuration mode.

Using the configuration modes (global, interface, and line), you can make changes to the running configuration. If you save the configuration, these commands are stored and used when the switch reboots. To access the various configuration modes, you must start at global configuration mode. From global configuration mode, you can enter interface configuration mode and line configuration mode .

This table describes the main command modes, how to access each one, the prompt you see in that mode, and how to exit the mode.

Command Mode Summary

Mode

Access Method

Prompt

Exit Method

About This Mode

User EXEC

Begin a session using Telnet, SSH, or console.

Switch>

Enter logout or quit.

Use this mode to

- Change terminal settings.

- Perform basic tests.

- Display system information.

Privileged EXEC

While in user EXEC mode, enter the enable command.

Switch#

Enter disable to exit.

Use this mode to verify commands that you have entered. Use a password to protect access to this mode.

Global configuration

While in privileged EXEC mode, enter the configure command.

Switch(config)#

To exit to privileged EXEC mode, enter exit or end, or press Ctrl-Z.

Use this mode to configure parameters that apply to the entire switch.

VLAN configuration

While in global configuration mode, enter the vlan vlan-id command.

Switch(config-vlan)#

To exit to global configuration mode, enter the exit command.

To return to privileged EXEC mode, press Ctrl-Z or enter end.

Use this mode to configure VLAN parameters. When VTP mode is transparent, you can create extended-range VLANs (VLAN IDs greater than 1005) and save configurations in the switch startup configuration file.

Interface configuration

While in global configuration mode, enter the interface command (with a specific interface).

Switch(config-if)#

To exit to global configuration mode, enter exit.

To return to privileged EXEC mode, press Ctrl-Z or enter end.

Use this mode to configure parameters for the Ethernet ports.

Line configuration

While in global configuration mode, specify a line with the line vty or line console command.

Switch(config-line)#

To exit to global configuration mode, enter exit.

To return to privileged EXEC mode, press Ctrl-Z or enter end.

Use this mode to configure parameters for the terminal line.

Understanding Abbreviated Commands

You need to enter only enough characters for the switch to recognize the command as unique.

This example shows how to enter the show configuration privileged EXEC command in an abbreviated form:

Switch# show conf

No and Default Forms of Commands

Almost every configuration command also has a no form. In general, use the no form to disable a feature or function or reverse the action of a command. For example, the no shutdown interface configuration command reverses the shutdown of an interface. Use the command without the keyword no to reenable a disabled feature or to enable a feature that is disabled by default.

Configuration commands can also have a default form. The default form of a command returns the command setting to its default. Most commands are disabled by default, so the default form is the same as the no form. However, some commands are enabled by default and have variables set to certain default values. In these cases, the default command enables the command and sets variables to their default values.

CLI Error Messages

This table lists some error messages that you might encounter while using the CLI to configure your switch.

Common CLI Error Messages

Error Message

Meaning

How to Get Help

% Ambiguous command: "show con"

You did not enter enough characters for your switch to recognize the command.

Reenter the command followed by a question mark (?) without any space between the command and the question mark.

The possible keywords that you can enter with the command appear.

% Incomplete command.

You did not enter all of the keywords or values required by this command.

Reenter the command followed by a question mark (?) with a space between the command and the question mark.

The possible keywords that you can enter with the command appear.

% Invalid input detected at ‘^’ marker.

You entered the command incorrectly. The caret (^) marks the point of the error.

Enter a question mark (?) to display all of the commands that are available in this command mode.

The possible keywords that you can enter with the command appear.

Configuration Logging

You can log and view changes to the switch configuration. You can use the Configuration Change Logging and Notification feature to track changes on a per-session and per-user basis. The logger tracks each configuration command that is applied, the user who entered the command, the time that the command was entered, and the parser return code for the command. This feature includes a mechanism for asynchronous notification to registered applications whenever the configuration changes. You can choose to have the notifications sent to the syslog.

Note

Only CLI or HTTP changes are logged.

Using the Help System

You can enter a question mark (?) at the system prompt to display a list of commands available for each command mode. You can also obtain a list of associated keywords and arguments for any command.

SUMMARY STEPS

1.    help

2.    abbreviated-command-entry ?

3.    abbreviated-command-entry <Tab>

4.    ?

5.    command ?

6.    command keyword ?

DETAILED STEPS

Command or Action

Purpose

Step 1

help

Example:

Switch# help

Obtains a brief description of the help system in any command mode.

Step 2

abbreviated-command-entry ?

Example:

Switch# di?
dir disable disconnect

Obtains a list of commands that begin with a particular character string.

Step 3

abbreviated-command-entry <Tab>

Example:

Switch# sh conf<tab>
Switch# show configuration

Completes a partial command name.

Step 4

?

Example:

Switch> ?

Lists all commands available for a particular command mode.

Step 5

command ?

Example:

Switch> show ?

Lists the associated keywords for a command.

Step 6

command keyword ?

Example:

Switch(config)# cdp holdtime ?
<10-255> Length of time (in sec) that receiver must keep this packet

Lists the associated arguments for a keyword.

Configuring the Command History

The software provides a history or record of commands that you have entered. The command history feature is particularly useful for recalling long or complex commands or entries, including access lists. You can customize this feature to suit your needs.

- Changing the Command History Buffer Size

- Recalling Commands

- Disabling the Command History Feature

Changing the Command History Buffer Size

By default, the switch records ten command lines in its history buffer. You can alter this number for a current terminal session or for all sessions on a particular line. This procedure is optional.

SUMMARY STEPS

1.    terminal history [size number-of-lines]

DETAILED STEPS

Command or Action

Purpose

Step 1

terminal history [size number-of-lines]

Example:

Switch# terminal history size 200

Changes the number of command lines that the switch records during the current terminal session in privileged EXEC mode. You can configure the size from 0 to 256.

Recalling Commands

To recall commands from the history buffer, perform one of the actions listed in this table. These actions are optional.

Note

The arrow keys function only on ANSI-compatible terminals such as VT100s.

SUMMARY STEPS

1.    Ctrl-P or use the up arrow key

2.    Ctrl-N or use the down arrow key

3.    show history

DETAILED STEPS

Command or Action

Purpose

Step 1

Ctrl-P or use the up arrow key

Recalls commands in the history buffer, beginning with the most recent command. Repeat the key sequence to recall successively older commands.

Step 2

Ctrl-N or use the down arrow key

Returns to more recent commands in the history buffer after recalling commands with Ctrl-P or the up arrow key. Repeat the key sequence to recall successively more recent commands.

Step 3

show history

Example:

Switch# show history

Lists the last several commands that you just entered in privileged EXEC mode. The number of commands that appear is controlled by the setting of the terminal history global configuration command and the history line configuration command.

Disabling the Command History Feature

The command history feature is automatically enabled. You can disable it for the current terminal session or for the command line. This procedure is optional.

SUMMARY STEPS

1.    terminal no history

DETAILED STEPS

Command or Action

Purpose

Step 1

terminal no history

Example:

Switch# terminal no history

Disables the feature during the current terminal session in privileged EXEC mode.

Enabling and Disabling Editing Features

Although enhanced editing mode is automatically enabled, you can disable it and reenable it.

SUMMARY STEPS

1.    terminal editing

2.    terminal no editing

DETAILED STEPS

Command or Action

Purpose

Step 1

terminal editing

Example:

Switch# terminal editing

Reenables the enhanced editing mode for the current terminal session in privileged EXEC mode.

Step 2

terminal no editing

Example:

Switch# terminal no editing

Disables the enhanced editing mode for the current terminal session in privileged EXEC mode.

- Editing Commands Through Keystrokes

- Editing Command Lines That Wrap

Editing Commands Through Keystrokes

The keystrokes help you to edit the command lines. These keystrokes are optional.

Note

The arrow keys function only on ANSI-compatible terminals such as VT100s.

Editing Commands

Editing Commands

Description

Ctrl-B or use the left arrow key

Moves the cursor back one character.

Ctrl-F or use the right arrow key

Moves the cursor forward one character.

Ctrl-A

Moves the cursor to the beginning of the command line.

Ctrl-E

Moves the cursor to the end of the command line.

Esc B

Moves the cursor back one word.

Esc F

Moves the cursor forward one word.

Ctrl-T

Transposes the character to the left of the cursor with the character located at the cursor.

Delete or Backspace key

Erases the character to the left of the cursor.

Ctrl-D

Deletes the character at the cursor.

Ctrl-K

Deletes all characters from the cursor to the end of the command line.

Ctrl-U or Ctrl-X

Deletes all characters from the cursor to the beginning of the command line.

Ctrl-W

Deletes the word to the left of the cursor.

Esc D

Deletes from the cursor to the end of the word.

Esc C

Capitalizes at the cursor.

Esc L

Changes the word at the cursor to lowercase.

Esc U

Capitalizes letters from the cursor to the end of the word.

Ctrl-V or Esc Q

Designates a particular keystroke as an executable command, perhaps as a shortcut.

Return key

Scrolls down a line or screen on displays that are longer than the terminal screen can display.

Note:
The More prompt is used for any output that has more lines than can be displayed on the terminal screen, including show command output. You can use the Return and Space bar keystrokes whenever you see the More prompt.

Space bar

Scrolls down one screen.

Ctrl-L or Ctrl-R

Redisplays the current command line if the switch suddenly sends a message to your screen.

Editing Command Lines That Wrap

You can use a wraparound feature for commands that extend beyond a single line on the screen. When the cursor reaches the right margin, the command line shifts ten spaces to the left. You cannot see the first ten characters of the line, but you can scroll back and check the syntax at the beginning of the command. The keystroke actions are optional.

To scroll back to the beginning of the command entry, press Ctrl-B or the left arrow key repeatedly. You can also press Ctrl-A to immediately move to the beginning of the line.

Note

The arrow keys function only on ANSI-compatible terminals such as VT100s.

The following example shows how to wrap a command line that extends beyond a single line on the screen.

SUMMARY STEPS

1.    access-list

2.    Ctrl-A

3.    Return key

DETAILED STEPS

Command or Action

Purpose

Step 1

access-list

Example:

Switch(config)# access-list 101 permit tcp 10.15.22.25 255.255.255.0 10.15.22.35
Switch(config)# $ 101 permit tcp 10.15.22.25 255.255.255.0 10.15.22.35 255.25
Switch(config)# $t tcp 10.15.22.25 255.255.255.0 131.108.1.20 255.255.255.0 eq
Switch(config)# $15.22.25 255.255.255.0 10.15.22.35 255.255.255.0 eq 45

Displays the global configuration command entry that extends beyond one line.

When the cursor first reaches the end of the line, the line is shifted ten spaces to the left and redisplayed. The dollar sign ($) shows that the line has been scrolled to the left. Each time the cursor reaches the end of the line, the line is again shifted ten spaces to the left.

Step 2

Ctrl-A

Example:

Switch(config)# access-list 101 permit tcp 10.15.22.25 255.255.255.0 10.15.2$

Checks the complete syntax.

The dollar sign ($) appears at the end of the line to show that the line has been scrolled to the right.

Step 3

Return key

Execute the commands.

The software assumes that you have a terminal screen that is 80 columns wide. If you have a different width, use the terminal width privileged EXEC command to set the width of your terminal.

Use line wrapping with the command history feature to recall and modify previous complex command entries.

Searching and Filtering Output of show and more Commands

You can search and filter the output for show and more commands. This is useful when you need to sort through large amounts of output or if you want to exclude output that you do not need to see. Using these commands is optional.

SUMMARY STEPS

1.    {show | more} command | {begin | include | exclude} regular-expression

DETAILED STEPS

Command or Action

Purpose

Step 1

{show | more} command | {begin | include | exclude} regular-expression

Example:

Switch# show interfaces | include protocol
Vlan1 is up, line protocol is up
Vlan10 is up, line protocol is down
GigabitEthernet1/0/1 is up, line protocol is down
GigabitEthernet1/0/2 is up, line protocol is up

Searches and filters the output.

Expressions are case sensitive. For example, if you enter | exclude output, the lines that contain output are not displayed, but the lines that contain output appear.

Accessing the CLI on a Switch Stack

You can access the CLI through a console connection, through Telnet, a SSH, or by using the browser.

You manage the switch stack and the stack member interfaces through the active switchstack master. You cannot manage stack members on an individual switch basis. You can connect to the active switchstack master through the console port or the Ethernet management port of one or more stack members. Be careful with using multiple CLI sessions on the active switchstack master. Commands that you enter in one session are not displayed in the other sessions. Therefore, it is possible to lose track of the session from which you entered commands.

Note

We recommend using one CLI session when managing the switch stack.

If you want to configure a specific stack member port, you must include the stack member number in the CLI command interface notation.

Accessing the CLI Through a Console Connection or Through Telnet

Before you can access the CLI, you must connect a terminal or a PC to the switch console or connect a PC to the Ethernet management port and then power on the switch, as described in the hardware installation guide that shipped with your switch.

If your switch is already configured, you can access the CLI through a local console connection or through a remote Telnet session, but your switch must first be configured for this type of access.

You can use one of these methods to establish a connection with the switch:

- Connect the switch console port to a management station or dial-up modem, or connect the Ethernet management port to a PC. For information about connecting to the console or Ethernet management port, see the switch hardware installation guide.

- Use any Telnet TCP/IP or encrypted Secure Shell (SSH) package from a remote management station. The switch must have network connectivity with the Telnet or SSH client, and the switch must have an enable secret password configured.

- The switch supports up to 16 simultaneous Telnet sessions. Changes made by one Telnet user are reflected in all other Telnet sessions.

- The switch supports up to five simultaneous secure SSH sessions.

After you connect through the console port, through the Ethernet management port, through a Telnet session or through an SSH session, the user EXEC prompt appears on the management station.

Chapter 2. Using the Web Graphical User Interface

- Prerequisites for Using the Web GUI

- Information About Using The Web GUI

- Connecting the Console Port of the Switch

- Logging On to the Web GUI

- Enabling Web and Secure Web Modes

- Configuring the Switch Web GUI

Prerequisites for Using the Web GUI

- Operating Systems:

- Windows 7

- Windows 8

- Mac OS X 10.8

- Browsers:

- Google Chrome, version 35

- Microsoft Internet Explorer, versions 10 or 11

- Mozilla Firefox, version 30 or later

- Safari, version 6.1

Information About Using The Web GUI

A web browser, or graphical user interface (GUI), is built into each switch.

You can use either the service port interface or the management interface to access the GUI. We recommend that you use the service-port interface. Click Help at the top of any page in the GUI to display online help. You might need to disable your browser’s pop-up blocker to view the online help.

- Web GUI Features

Web GUI Features

The switch web GUI supports the following:

The Configuration Wizard—After initial configuration of the IP address and the local username/password or auth via the authentication server (privilege 15 needed), the wizard provides a method to complete the initial wireless configuration. Start the wizard through Configuration -> Wizard and follow the nine-step process to configure the following:

- Admin Users

- SNMP System Summary

- Management Port

- Wireless Management

- RF Mobility and Country code

- Mobility configuration

- WLANs

- 802.11 Configuration

- Set Time

The Monitor tab:

- Displays summary details of switch, clients, and access points.

- Displays all radio and AP join statistics.

- Displays air quality on access points.

- Displays list of all Cisco Discovery Protocol (CDP) neighbors on all interfaces and the CDP traffic information.

- Displays all rogue access points based on their classification-friendly, malicious, ad hoc, classified, and unclassified.

The Configuration tab:

- Enables you to configure the switch for all initial operation using the web Configuration Wizard. The wizard allows you to configure user details, management interface, and so on.

- Enables you to configure the system, internal DHCP server, management, and mobility management parameters.

- Enables you to configure the switch, WLAN, and radios.

- Enables you to configure and set security policies on your switch.

- Enables you to access the switch operating system software management commands.

The Administration tab enables you to configure system logs.

Connecting the Console Port of the Switch

Before You Begin

Before you can configure the switch for basic operations, you need to connect it to a PC that uses a VT-100 terminal emulation program (such as HyperTerminal, ProComm, Minicom, or Tip).

Step 1

Connect one end of a null-modem serial cable to the switch's RJ-45 console port and the other end to your PC's serial port.

Step 2

Plug the AC power cord into the switch and a grounded 100 to 240 VAC, 50/60-Hz electrical outlet. Turn on the power supply. The bootup script displays operating system software initialization (code download and power-on self-test verification) and basic configuration. If the switch passes the power-on self-test, the bootup script runs the configuration wizard, which prompts you for basic configuration input.

Step 3

Enter yes. Proceed with basic initial setup configuration parameters in the CLI setup wizard. Specify the IP address for the service port which is the gigabitethernet 0/0 interface.
After entering the configuration parameters in the configuration wizard, you can access the Web GUI. Now, the switch is configured with the IP address for service port.

Logging On to the Web GUI

Enter the switch IP address in your browser’s address bar. For a secure connection, enter https://ip-address. For a less secure connection, enter http://ip-address.

Enabling Web and Secure Web Modes

Step 1

Choose Configuration > Management > Protocol Management > HTTP-HTTPS.

The HTTP-HTTPS Configuration page appears.

Step 2

To enable web mode, which allows users to access the switch GUI using “http://ip-address,” choose Enabled from the HTTP Access drop-down list. Otherwise, choose Disabled. Web mode (HTTP) is not a secure connection.

Step 3

To enable secure web mode, which allows users to access the switch GUI using “https://ip-address,” choose Enabled from the HTTPS Access drop-down list. Otherwise, choose Disabled. Secure web mode (HTTPS) is a secure connection.

Step 4

Choose to track the device in the IP Device Tracking check box.

Step 5

Choose to enable the trust point in the Enable check box.

Step 6

Choose the trustpoints from the Trustpoints drop-down list.

Step 7

Enter the amount of time, in seconds, before the web session times out due to inactivity in the HTTP Timeout-policy (1 to 600 sec) text box.
The valid range is from 1 to 600 seconds.

Step 8

Enter the server life time in the Server Life Time (1 to 86400 sec) text box.
The valid range is from1 to 86400 seconds.

Step 9

Enter the maximum number of connection requests that the server can accept in the Maximum number of Requests (1 to 86400) text box.
The valid range is from 1 to 86400 connections.

Step 10

Click Apply.

Step 11

Click Save Configuration.

Configuring the Switch Web GUI

The configuration wizard enables you to configure basic settings on the switch. You can run the wizard after you receive the switch from the factory or after the switch has been reset to factory defaults. The configuration wizard is available in both GUI and CLI formats.

Step 1

Connect your PC to the service port and configure an IPv4 address to use the same subnet as the switch. The switch is loaded with IOS XE image and the service port interface is configured as gigabitethernet 0/0.

Step 2

Start Internet Explorer 10 (or later), Firefox 2.0.0.11 (or later), or Google Chrome on your PC and enter the management interface IP address on the browser window. The management interface IP address is same as the gigabitethernet 0/0 (also known as service port interface). When you log in for the first time, you need to enter HTTP username and password. By default, the username is admin and the password is cisco.
You can use both HTTP and HTTPS when using the service port interface. HTTPS is enabled by default and HTTP can also be enabled.

When you log in for the first time, the <Model Number> <Hostname> page appears.

Step 3

On the page, click the Wireless Web GUI link to access switch web GUI Home page.

Step 4

Choose Configuration > Wizard to perform all steps that you need to configure the switch initially.
The Admin Users page appears.

Step 5

On the Admin Users page, enter the administrative username to be assigned to this switch in the User Name text box and the administrative password to be assigned to this switch in the Password and Confirm Password text boxes. Click Next.
The default username is admin and the default password is cisco. You can also create a new administrator user for the switch. You can enter up to 24 ASCII characters for username and password.

The SNMP System Summary page appears.

Step 6

On the SNMP System Summary page, enter the following SNMP system parameters for the switch, and click Next:

- Customer-definable switch location in the Location text box.

- Customer-definable contact details such as phone number with names in the Contact text box.

- Choose enabled to send SNMP notifications for various SNMP traps or disabled not to send SNMP notifications for various SNMP traps from the SNMP Global Trap drop-down list.

- Choose enabled to send system log messages or disabled not to send system log messages from the SNMP Logging drop-down list.

Note:
The SNMP trap server, must be reachable through the distribution ports (and not through the gigabitethernet0/0 service or management interface).

The Management Port page appears.

Step 7

In the Management Port page, enter the following parameters for the management port interface (gigabitethernet 0/0) and click Next.

- Interface IP address that you assigned for the service port in the IP Address text box.

- Network mask address of the management port interface in the Netmask text box.

- The IPv4 Dynamic Host Configuration Protocol (DHCP) address for the selected port in the IPv4 DHCP Server text box.

The Wireless Management page appears.

Step 8

In the Wireless Management page, enter the following wireless interface management details, and click Next.

- Choose the interface—VLAN, or Ten Gigabit Ethernet from the Select Interface drop-down list.

- VLAN tag identifier, or 0 for no VLAN tag in the VLAN id text box.

- IP address of wireless management interface where access points are connected in the IP Address text box.

- Network mask address of the wireless management interface in the Netmask text box.

- DHCP IPv4 IP address in the IPv4 DHCP Server text box.

When selecting VLAN as interface, you can specify the ports as –Trunk or Access ports from the selected list displayed in the Switch Port Configuration text box.

The RF Mobility and Country Code page appears.

Step 9

In the RF Mobility and Country Code page, enter the RF mobility domain name in the RF Mobility text box, choose current country code from the Country Code drop-down list, and click Next. From the GUI, you can select only one country code.

Note:   Before configuring RF grouping parameters and mobility configuration, ensure that you refer to the relevant conceptual content and then proceed with the configuration.

The Mobility Configuration page with mobility global configuration settings appears.

Step 10

In the Mobility Configuration page, view and enter the following mobility global configuration settings, and click Next.

- Choose Mobility Controller or Mobility Agent from the Mobility Role drop-down list:

- If Mobility Agent is chosen, enter the mobility controller IP address in the Mobility Controller IP Address text box and mobility controller IP address in the Mobility Controller Public IP Address text box.

- If Mobility Controller is chosen, then the mobility controller IP address and mobility controller public IP address are displayed in the respective text boxes.

- Displays mobility protocol port number in the Mobility Protocol Port text box.

- Displays the mobility switch peer group name in the Mobility Switch Peer Group Name text box.

- Displays whether DTLS is enabled in the DTLS Mode text box.

DTLS is a standards-track Internet Engineering Task Force (IETF) protocol based on TLS.

- Displays mobility domain identifier for 802.11 radios in the Mobility Domain ID for 802.11 radios text box.

- The amount of time (in seconds) between each ping request sent to an peer switch in the Mobility Keepalive Interval (1-30)sec text box.

Valid range is from 1 to 30 seconds, and the default value is 10 seconds.

- Number of times a ping request is sent to an peer switch before the peer is considered to be unreachable in the Mobility Keepalive Count (3-20) text box.

The valid range is from 3 to 20, and the default value is 3.

- The DSCP value that you can set for the mobility switch in the Mobility Control Message DSCP Value (0-63) text box.

The valid range is 0 to 63, and the default value is 0.

- Displays the number of mobility switch peer group member configured in the Switch Peer Group Members Configured text box.

The WLANs page appears.

Step 11

In the WLANs page, enter the following WLAN configuration parameters, and click Next.

- WLAN identifier in the WLAN ID text box.

- SSID of the WLAN that the client is associated with in the SSID text box.

- Name of the WLAN used by the client in the Profile Name text box.

The 802.11 Configuration page appears.

Step 12

In the 802.11 Configuration page, check either one or both 802.11a/n/ac and 802.11b/g/n check boxes to enable the 802.11 radios, and click Next.
The Set Time page appears.

Step 13

In the Set Time page, you can configure the time and date on the switch based on the following parameters, and click Next.

- Displays current timestamp on the switch in the Current Time text box.

- Choose either Manual or NTP from the Mode drop-down list.

On using the NTP server, all access points connected to the switch, synchronizes its time based on the NTP server settings available.

- Choose date on the switch from the Year, Month, and Day drop-down list.

- Choose time from the Hours, Minutes, and Seconds drop-down list.

- Enter the time zone in the Zone text box and select the off setting required when compared to the current time configured on the switch from the Offset drop-down list.

The Save Wizard page appears.

Step 14

In the Save Wizard page, you can review the configuration settings performed on the switch using these steps, and if you wish to change any configuration value, click Previous and navigate to that page.
You can save the switch configuration created using the wizard only if a success message is displayed for all the wizards. If the Save Wizard page displays errors, you must recreate the wizard for initial configuration of the switch.

Chapter 3. Configuring Interface Characteristics

- Finding Feature Information

- Information About Configuring Interface Characteristics

- How to Configure Interface Characteristics

- Monitoring Interface Characteristics

- Configuration Examples for Interface Characteristics

- Additional References for the Interface Characteristics Feature

- Feature History and Information for Configuring Interface Characteristics

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to Click Here . An account on Cisco.com is not required.

Information About Configuring Interface Characteristics

- Interface Types

- Using the Switch USB Ports

- Interface Connections

- Interface Configuration Mode

- Default Ethernet Interface Configuration

- Interface Speed and Duplex Mode

- Speed and Duplex Configuration Guidelines

- IEEE 802.3x Flow Control

- Layer 3 Interfaces

Interface Types

This section describes the different types of interfaces supported by the switch. The rest of the chapter describes configuration procedures for physical interface characteristics.

Note

The stack ports on the rear of the stacking-capable switches are not Ethernet ports and cannot be configured.

- Port-Based VLANs

- Switch Ports

- Routed Ports

- Switch Virtual Interfaces

- EtherChannel Port Groups

- 10-Gigabit Ethernet Interfaces

- Power over Ethernet Ports

Port-Based VLANs

A VLAN is a switched network that is logically segmented by function, team, or application, without regard to the physical location of the users. Packets received on a port are forwarded only to ports that belong to the same VLAN as the receiving port. Network devices in different VLANs cannot communicate with one another without a Layer 3 device to route traffic between the VLANs.

VLAN partitions provide hard firewalls for traffic in the VLAN, and each VLAN has its own MAC address table. A VLAN comes into existence when a local port is configured to be associated with the VLAN, when the VLAN Trunking Protocol (VTP) learns of its existence from a neighbor on a trunk, or when a user creates a VLAN. VLANs can be formed with ports across the stack.

To configure VLANs, use the vlan vlan-id global configuration command to enter VLAN configuration mode. The VLAN configurations for normal-range VLANs (VLAN IDs 1 to 1005) are saved in the VLAN database. If VTP is version 1 or 2, to configure extended-range VLANs (VLAN IDs 1006 to 4094), you must first set VTP mode to transparent. Extended-range VLANs created in transparent mode are not added to the VLAN database but are saved in the switch running configuration. With VTP version 3, you can create extended-range VLANs in client or server mode. These VLANs are saved in the VLAN database.

In a switch stack, the VLAN database is downloaded to all switches in a stack, and all switches in the stack build the same VLAN database. The running configuration and the saved configuration are the same for all switches in a stack.

Add ports to a VLAN by using the switchport interface configuration commands:

- Identify the interface.

- For a trunk port, set trunk characteristics, and, if desired, define the VLANs to which it can belong.

- For an access port, set and define the VLAN to which it belongs.

Switch Ports

Switch ports are Layer 2-only interfaces associated with a physical port. Switch ports belong to one or more VLANs. A switch port can be an access port or a trunk port. You can configure a port as an access port or trunk port or let the Dynamic Trunking Protocol (DTP) operate on a per-port basis to set the switchport mode by negotiating with the port on the other end of the link. switch ports are used for managing the physical interface and associated Layer 2 protocols and do not handle routing or bridging.

Configure switch ports by using the switchport interface configuration commands.

- Access Ports

- Trunk Ports

- Tunnel Ports

Access Ports

An access port belongs to and carries the traffic of only one VLAN (unless it is configured as a voice VLAN port). Traffic is received and sent in native formats with no VLAN tagging. Traffic arriving on an access port is assumed to belong to the VLAN assigned to the port. If an access port receives a tagged packet (Inter-Switch Link [ISL] or IEEE 802.1Q tagged), the packet is dropped, and the source address is not learned.

The types of access ports supported are:

- Static access ports are manually assigned to a VLAN (or through a RADIUS server for use with IEEE 802.1x.

You can also configure an access port with an attached Cisco IP Phone to use one VLAN for voice traffic and another VLAN for data traffic from a device attached to the phone.

Trunk Ports

A trunk port carries the traffic of multiple VLANs and by default is a member of all VLANs in the VLAN database.

Although by default, a trunk port is a member of every VLAN known to the VTP, you can limit VLAN membership by configuring an allowed list of VLANs for each trunk port. The list of allowed VLANs does not affect any other port but the associated trunk port. By default, all possible VLANs (VLAN ID 1 to 4094) are in the allowed list. A trunk port can become a member of a VLAN only if VTP knows of the VLAN and if the VLAN is in the enabled state. If VTP learns of a new, enabled VLAN and the VLAN is in the allowed list for a trunk port, the trunk port automatically becomes a member of that VLAN and traffic is forwarded to and from the trunk port for that VLAN. If VTP learns of a new, enabled VLAN that is not in the allowed list for a trunk port, the port does not become a member of the VLAN, and no traffic for the VLAN is forwarded to or from the port.

Tunnel Ports

Tunnel ports are used in IEEE 802.1Q tunneling to segregate the traffic of customers in a service-provider network from other customers who are using the same VLAN number. You configure an asymmetric link from a tunnel port on a service-provider edge switch to an IEEE 802.1Q trunk port on the customer switch. Packets entering the tunnel port on the edge switch, already IEEE 802.1Q-tagged with the customer VLANs, are encapsulated with another layer of an IEEE 802.1Q tag (called the metro tag), containing a VLAN ID unique in the service-provider network, for each customer. The double-tagged packets go through the service-provider network keeping the original customer VLANs separate from those of other customers. At the outbound interface, also a tunnel port, the metro tag is removed, and the original VLAN numbers from the customer network are retrieved.

Tunnel ports cannot be trunk ports or access ports and must belong to a VLAN unique to each customer.

Routed Ports

A routed port is a physical port that acts like a port on a router; it does not have to be connected to a router. A routed port is not associated with a particular VLAN, as is an access port. A routed port behaves like a regular router interface, except that it does not support VLAN subinterfaces. Routed ports can be configured with a Layer 3 routing protocol. A routed port is a Layer 3 interface only and does not support Layer 2 protocols, such as DTP and STP.

Configure routed ports by putting the interface into Layer 3 mode with the no switchport interface configuration command. Then assign an IP address to the port, enable routing, and assign routing protocol characteristics by using the ip routing and router protocol global configuration commands.

Note

Entering a no switchport interface configuration command shuts down the interface and then re-enables it, which might generate messages on the device to which the interface is connected. When you put an interface that is in Layer 2 mode into Layer 3 mode, the previous configuration information related to the affected interface might be lost.

The number of routed ports that you can configure is not limited by software. However, the interrelationship between this number and the number of other features being configured might impact CPU performance because of hardware limitations.

Note

The IP Base image supports static routing and the Routing Information Protocol (RIP). For full Layer 3 routing or for fallback bridging, you must enable the IP Services image on the standalone switch, or the active switch.

Switch Virtual Interfaces

A switch virtual interface (SVI) represents a VLAN of switch ports as one interface to the routing or bridging function in the system. You can associate only one SVI with a VLAN. You configure an SVI for a VLAN only to route between VLANs or to provide IP host connectivity to the switch. By default, an SVI is created for the default VLAN (VLAN 1) to permit remote switch administration. Additional SVIs must be explicitly configured.

Note

You cannot delete interface VLAN 1.

SVIs provide IP host connectivity only to the system. SVIs are created the first time that you enter the vlan interface configuration command for a VLAN interface. The VLAN corresponds to the VLAN tag associated with data frames on an ISL or IEEE 802.1Q encapsulated trunk or the VLAN ID configured for an access port. Configure a VLAN interface for each VLAN for which you want to route traffic, and assign it an IP address.

Although the switch stack or switch supports a total of 1005 VLANs and SVIs, the interrelationship between the number of SVIs and routed ports and the number of other features being configured might impact CPU performance because of hardware limitations.

When you create an SVI, it does not become active until it is associated with a physical port.

- SVI Autostate Exclude

SVI Autostate Exclude

The line state of an SVI with multiple ports on a VLAN is in the up state when it meets these conditions:

- The VLAN exists and is active in the VLAN database on the switch

- The VLAN interface exists and is not administratively down.

- At least one Layer 2 (access or trunk) port exists, has a link in the up state on this VLAN, and is in the spanning-tree forwarding state on the VLAN.

Note

The protocol link state for VLAN interfaces come up when the first switchport belonging to the corresponding VLAN link comes up and is in STP forwarding state.

The default action, when a VLAN has multiple ports, is that the SVI goes down when all ports in the VLAN go down. You can use the SVI autostate exclude feature to configure a port so that it is not included in the SVI line-state up-or-down calculation. For example, if the only active port on the VLAN is a monitoring port, you might configure autostate exclude on that port so that the VLAN goes down when all other ports go down. When enabled on a port, autostate exclude applies to all VLANs that are enabled on that port.

The VLAN interface is brought up when one Layer 2 port in the VLAN has had time to converge (transition from STP listening-learning state to forwarding state). This prevents features such as routing protocols from using the VLAN interface as if it were fully operational and minimizes other problems, such as routing black holes.

EtherChannel Port Groups

EtherChannel port groups treat multiple switch ports as one switch port. These port groups act as a single logical port for high-bandwidth connections between switches or between switches and servers. An EtherChannel balances the traffic load across the links in the channel. If a link within the EtherChannel fails, traffic previously carried over the failed link changes to the remaining links. You can group multiple trunk ports into one logical trunk port, group multiple access ports into one logical access port, group multiple tunnel ports into one logical tunnel port, or group multiple routed ports into one logical routed port. Most protocols operate over either single ports or aggregated switch ports and do not recognize the physical ports within the port group. Exceptions are the DTP, the Cisco Discovery Protocol (CDP), and the Port Aggregation Protocol (PAgP), which operate only on physical ports.

When you configure an EtherChannel, you create a port-channel logical interface and assign an interface to the EtherChannel. For Layer 3 interfaces, you manually create the logical interface by using the interface port-channel global configuration command. Then you manually assign an interface to the EtherChannel by using the channel-group interface configuration command. For Layer 2 interfaces, use the channel-group interface configuration command to dynamically create the port-channel logical interface. This command binds the physical and logical ports together.

10-Gigabit Ethernet Interfaces

A 10-Gigabit Ethernet interface operates only in full-duplex mode. The interface can be configured as a switched or routed port.

For more information about the Cisco TwinGig Converter Module, see the switch hardware installation guide and your transceiver module documentation.

Power over Ethernet Ports

A PoE-capable switch port automatically supplies power to one of these connected devices if the switch senses that there is no power on the circuit:

- a Cisco pre-standard powered device (such as a Cisco IP Phone or a Cisco Aironet Access Point)

- an IEEE 802.3af-compliant powered device

A powered device can receive redundant power when it is connected to a PoE switch port and to an AC power source. The device does not receive redundant power when it is only connected to the PoE port.

Using the Switch USB Ports

The switch has two USB ports on the front panel — a USB mini-Type B console port and a USB Type A port.

- USB Mini-Type B Console Port

- USB Type A Port

USB Mini-Type B Console Port

The switch has the following console ports:

- USB mini-Type B console connection

- RJ-45 console port

Console output appears on devices connected to both ports, but console input is active on only one port at a time. By default, the USB connector takes precedence over the RJ-45 connector.

Note

Windows PCs require a driver for the USB port. See the hardware installation guide for driver installation instructions.

Use the supplied USB Type A-to-USB mini-Type B cable to connect a PC or other device to the switch. The connected device must include a terminal emulation application. When the switch detects a valid USB connection to a powered-on device that supports host functionality (such as a PC), input from the RJ-45 console is immediately disabled, and input from the USB console is enabled. Removing the USB connection immediately reenables input from the RJ-45 console connection. An LED on the switch shows which console connection is in use.

- Console Port Change Logs

Console Port Change Logs

At software startup, a log shows whether the USB or the RJ-45 console is active. Each switch in a stack issues this log. Every switch always first displays the RJ-45 media type.

In the sample output, Switch 1 has a connected USB console cable. Because the bootloader did not change to the USB console, the first log from Switch 1 shows the RJ-45 console. A short time later, the console changes and the USB console log appears. Switch 2 and Switch 3 have connected RJ-45 console cables.

switch-stack-1
*Mar  1 00:01:00.171: %USB_CONSOLE-6-MEDIA_RJ45: Console media-type is RJ45.
*Mar  1 00:01:00.431: %USB_CONSOLE-6-MEDIA_USB: Console media-type is USB.

switch-stack-2
*Mar  1 00:01:09.835: %USB_CONSOLE-6-MEDIA_RJ45: Console media-type is RJ45.

switch-stack-3
*Mar  1 00:01:10.523: %USB_CONSOLE-6-MEDIA_RJ45: Console media-type is RJ45.

When the USB cable is removed or the PC de-activates the USB connection, the hardware automatically changes to the RJ-45 console interface:

switch-stack-1
Mar  1 00:20:48.635: %USB_CONSOLE-6-MEDIA_RJ45: Console media-type is RJ45.

You can configure the console type to always be RJ-45, and you can configure an inactivity timeout for the USB connector.

USB Type A Port

The USB Type A port provides access to external USB flash devices, also known as thumb drives or USB keys. The port supports Cisco USB flash drives with capacities from 128 MB to 8 GB (USB devices with port densities of 128 MB, 256 MB, 1 GB, 4 GB, 8 GB are supported). You can use standard Cisco IOS command- line interface (CLI) commands to read, write, erase, and copy to or from the flash device. You can also configure the switch to boot from the USB flash drive.

Interface Connections

Devices within a single VLAN can communicate directly through any switch. Ports in different VLANs cannot exchange data without going through a routing device. With a standard Layer 2 switch, ports in different VLANs have to exchange information through a router. By using the switch with routing enabled, when you configure both VLAN 20 and VLAN 30 with an SVI to which an IP address is assigned, packets can be sent from Host A to Host B directly through the switch with no need for an external router.

Connecting VLANs with the Switch

When the IP Services image is running on the switch or the active switch, the switch uses two methods to forward traffic between interfaces: routing and fallback bridging. If the IP Base image is on the switch or the active switch, only basic routing (static routing and RIP) is supported. Whenever possible, to maintain high performance, forwarding is done by the switch hardware. However, only IPv4 packets with Ethernet II encapsulation are routed in hardware. Non-IP traffic and traffic with other encapsulation methods are fallback-bridged by hardware.

- The routing function can be enabled on all SVIs and routed ports. The switch routes only IP traffic. When IP routing protocol parameters and address configuration are added to an SVI or routed port, any IP traffic received from these ports is routed.

- Fallback bridging forwards traffic that the switch does not route or traffic belonging to a nonroutable protocol, such as DECnet. Fallback bridging connects multiple VLANs into one bridge domain by bridging between two or more SVIs or routed ports. When configuring fallback bridging, you assign SVIs or routed ports to bridge groups with each SVI or routed port assigned to only one bridge group. All interfaces in the same group belong to the same bridge domain.

Interface Configuration Mode

The switch supports these interface types:

- Physical ports—switch ports and routed ports

- VLANs—switch virtual interfaces

- Port channels—EtherChannel interfaces

You can also configure a range of interfaces.

To configure a physical interface (port), specify the interface type, stack member number (only stacking-capable switches), module number, and switch port number, and enter interface configuration mode.

- Type—Gigabit Ethernet (gigabitethernet or gi) for 10/100/1000 Mb/s Ethernet ports, 10-Gigabit Ethernet (tengigabitethernet or te) for 10,000 Mb/s, or small form-factor pluggable (SFP) module Gigabit Ethernet interfaces (gigabitethernet or gi).

- Stack member number—The number that identifies the switch within the stack. The switch number range is 1 to 9 and is assigned the first time the switch initializes. The default switch number, before it is integrated into a switch stack, is 1. When a switch has been assigned a stack member number, it keeps that number until another is assigned to it.

You can use the switch port LEDs in Stack mode to identify the stack member number of a switch.

- Module number—The module or slot number on the switch: switch (downlink) ports are 0, and uplink ports are 1.

- Port number—The interface number on the switch. The 10/100/1000 port numbers always begin at 1, starting with the far left port when facing the front of the switch, for example, gigabitethernet1/0/1 or gigabitethernet1/0/8.

On a switch with SFP uplink ports, the module number is 1 and the port numbers restart. For example, if the switch has 24 10/100/1000 ports, the SFP module ports are gigabitethernet1/1/1 through gigabitethernet1/1/4 or tengigabitethernet1/1/1 through tengigabitethernet1/1/4.

You can identify physical interfaces by physically checking the interface location on the switch. You can also use the show privileged EXEC commands to display information about a specific interface or all the interfaces on the switch. The remainder of this chapter primarily provides physical interface configuration procedures.

These are examples of how to identify interfaces on a stacking-capable switch:

- To configure 10/100/1000 port 4 on a standalone switch, enter this command:

Switch(config)# interface gigabitethernet1/0/4

- To configure 10-Gigabit Ethernet port 1 on a standalone switch, enter this command:

Switch(config)# interface tengigabitethernet1/0/1

- To configure 10-Gigabit Ethernet port on stack member 3, enter this command:

Switch(config)# interface tengigabitethernet3/0/1

- To configure the first SFP module (uplink) port on a standalone switch, enter this command:

Switch(config)# interface gigabitethernet1/1/1

Default Ethernet Interface Configuration

To configure Layer 2 parameters, if the interface is in Layer 3 mode, you must enter the switchport interface configuration command without any parameters to put the interface into Layer 2 mode. This shuts down the interface and then re-enables it, which might generate messages on the device to which the interface is connected. When you put an interface that is in Layer 3 mode into Layer 2 mode, the previous configuration information related to the affected interface might be lost, and the interface is returned to its default configuration.

This table shows the Ethernet interface default configuration, including some features that apply only to Layer 2 interfaces.

Default Layer 2 Ethernet Interface Configuration

Feature

Default Setting

Operating mode

Layer 2 or switching mode (switchport command).

Allowed VLAN range

VLANs 1– 4094.

Default VLAN (for access ports)

VLAN 1 (Layer 2 interfaces only).

Native VLAN (for IEEE 802.1Q trunks)

VLAN 1 (Layer 2 interfaces only).

VLAN trunking

Switchport mode dynamic auto (supports DTP) (Layer 2 interfaces only).

Port enable state

All ports are enabled.

Port description

None defined.

Speed

Autonegotiate. (Not supported on the 10-Gigabit interfaces.)

Duplex mode

Autonegotiate. (Not supported on the 10-Gigabit interfaces.)

Flow control

Flow control is set to receive: off. It is always off for sent packets.

EtherChannel (PAgP)

Disabled on all Ethernet ports.

Port blocking (unknown multicast and unknown unicast traffic)

Disabled (not blocked) (Layer 2 interfaces only).

Broadcast, multicast, and unicast storm control

Disabled.

Protected port

Disabled (Layer 2 interfaces only).

Port security

Disabled (Layer 2 interfaces only).

Port Fast

Disabled.

Auto-MDIX

Enabled.

Note:
The switch might not support a pre-standard powered device—such as Cisco IP phones and access points that do not fully support IEEE 802.3af—if that powered device is connected to the switch through a crossover cable. This is regardless of whether auto-MIDX is enabled on the switch port.

Power over Ethernet (PoE)

Enabled (auto).

Interface Speed and Duplex Mode

Ethernet interfaces on the switch operate at 10, 100, 1000, or 10,000 Mb/s and in either full- or half-duplex mode. In full-duplex mode, two stations can send and receive traffic at the same time. Normally, 10-Mb/s ports operate in half-duplex mode, which means that stations can either receive or send traffic.

Switch models include Gigabit Ethernet (10/100/1000-Mb/s) ports, 10-Gigabit Ethernet ports, and small form-factor pluggable (SFP) module slots supporting SFP modules.

Speed and Duplex Configuration Guidelines

When configuring an interface speed and duplex mode, note these guidelines:

- The 10-Gigabit Ethernet ports do not support the speed and duplex features. These ports operate only at 10,000 Mb/s and in full-duplex mode.

- Gigabit Ethernet (10/100/1000-Mb/s) ports support all speed options and all duplex options (auto, half, and full). However, Gigabit Ethernet ports operating at 1000 Mb/s do not support half-duplex mode.

- For SFP module ports, the speed and duplex CLI options change depending on the SFP module type:

- The 1000BASE-x (where -x is -BX, -CWDM, -LX, -SX, and -ZX) SFP module ports support the nonegotiate keyword in the speed interface configuration command. Duplex options are not supported.

- The 1000BASE-T SFP module ports support the same speed and duplex options as the 10/100/1000-Mb/s ports.

- If both ends of the line support autonegotiation, we highly recommend the default setting of auto negotiation.

- If one interface supports autonegotiation and the other end does not, configure duplex and speed on both interfaces; do not use the auto setting on the supported side.

- When STP is enabled and a port is reconfigured, the switch can take up to 30 seconds to check for loops. The port LED is amber while STP reconfigures.

Caution

Changing the interface speed and duplex mode configuration might shut down and re-enable the interface during the reconfiguration.

IEEE 802.3x Flow Control

Flow control enables connected Ethernet ports to control traffic rates during congestion by allowing congested nodes to pause link operation at the other end. If one port experiences congestion and cannot receive any more traffic, it notifies the other port by sending a pause frame to stop sending until the condition clears. Upon receipt of a pause frame, the sending device stops sending any data packets, which prevents any loss of data packets during the congestion period.

Note

The switch ports can receive, but not send, pause frames.

You use the flowcontrol interface configuration command to set the interface’s ability to receive pause frames to on, off, or desired. The default state is off.

When set to desired, an interface can operate with an attached device that is required to send flow-control packets or with an attached device that is not required to but can send flow-control packets.

These rules apply to flow control settings on the device:

- receive on (or desired): The port cannot send pause frames but can operate with an attached device that is required to or can send pause frames; the port can receive pause frames.

- receive off: Flow control does not operate in either direction. In case of congestion, no indication is given to the link partner, and no pause frames are sent or received by either device.

Note

For details on the command settings and the resulting flow control resolution on local and remote ports, see the flowcontrol interface configuration command in the command reference for this release.

Layer 3 Interfaces

The switch supports these types of Layer 3 interfaces:

- SVIs: You should configure SVIs for any VLANs for which you want to route traffic. SVIs are created when you enter a VLAN ID following the interface vlan global configuration command. To delete an SVI, use the no interface vlan global configuration command. You cannot delete interface VLAN 1.

Note

When you create an SVI, it does not become active until it is associated with a physical port.

When configuring SVIs, you can also configure SVI autostate exclude on a port in the SVI to exclude that port from being included in determining SVI line-state status.

- Routed ports: Routed ports are physical ports configured to be in Layer 3 mode by using the no switchport interface configuration command.

- Layer 3 EtherChannel ports: EtherChannel interfaces made up of routed ports.

A Layer 3 switch can have an IP address assigned to each routed port and SVI.

There is no defined limit to the number of SVIs and routed ports that can be configured in a switch or in a switch stack. However, the interrelationship between the number of SVIs and routed ports and the number of other features being configured might have an impact on CPU usage because of hardware limitations. If the switch is using its maximum hardware resources, attempts to create a routed port or SVI have these results:

- If you try to create a new routed port, the switch generates a message that there are not enough resources to convert the interface to a routed port, and the interface remains as a switchport.

- If you try to create an extended-range VLAN, an error message is generated, and the extended-range VLAN is rejected.

- If the switch is notified by VLAN Trunking Protocol (VTP) of a new VLAN, it sends a message that there are not enough hardware resources available and shuts down the VLAN. The output of the show vlan user EXEC command shows the VLAN in a suspended state.

- If the switch attempts to boot up with a configuration that has more VLANs and routed ports than hardware can support, the VLANs are created, but the routed ports are shut down, and the switch sends a message that this was due to insufficient hardware resources.

All Layer 3 interfaces require an IP address to route traffic. This procedure shows how to configure an interface as a Layer 3 interface and how to assign an IP address to an interface.

Note

If the physical port is in Layer 2 mode (the default), you must enter the no switchport interface configuration command to put the interface into Layer 3 mode. Entering a no switchport command disables and then re-enables the interface, which might generate messages on the device to which the interface is connected. Furthermore, when you put an interface that is in Layer 2 mode into Layer 3 mode, the previous configuration information related to the affected interface might be lost, and the interface is returned to its default configuration

How to Configure Interface Characteristics

- Configuring Interfaces

- Adding a Description for an Interface

- Configuring a Range of Interfaces

- Configuring and Using Interface Range Macros

- Configuring Ethernet Interfaces

- Configuring IEEE 802.3x Flow Control

- Configuring Layer 3 Interfaces

- Configuring SVI Autostate Exclude

- Shutting Down and Restarting the Interface

- Configuring the Console Media Type

- Configuring the USB Inactivity Timeout

Configuring Interfaces

These general instructions apply to all interface configuration processes.

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters the global configuration mode.

Step 3

interface

Example:

Switch(config)# interface gigabitethernet1/0/1
Switch(config-if)#

Identifies the interface type, the switch number (only on stacking-capable switches), and the number of the connector.

Note:
You do not need to add a space between the interface type and the interface number. For example, in the preceding line, you can specify either gigabitethernet 1/0/1, gigabitethernet1/0/1, gi 1/0/1, or gi1/0/1.

Step 4

Follow each interface command with the interface configuration commands that the interface requires.

Defines the protocols and applications that will run on the interface. The commands are collected and applied to the interface when you enter another interface command or enter end to return to privileged EXEC mode.

Step 5

interface range or interface range macro

(Optional) Configures a range of interfaces.
Note:
Interfaces configured in a range must be the same type and must be configured with the same feature options.

Step 6

show interfaces

Displays a list of all interfaces on or configured for the switch. A report is provided for each interface that the device supports or for the specified interface.

Adding a Description for an Interface

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    interface interface-id

4.    description string

5.    end

6.    show interfaces interface-id description

7.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

interface interface-id

Example:

Switch(config)# interface gigabitethernet1/0/2

Specifies the interface for which you are adding a description, and enter interface configuration mode.

Step 4

description string

Example:

Switch(config-if)# description Connects to Marketing

Adds a description (up to 240 characters) for an interface.

Step 5

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Step 6

show interfaces interface-id description

Verifies your entry.

Step 7

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Configuring a Range of Interfaces

To configure multiple interfaces with the same configuration parameters, use the interface range global configuration command. When you enter the interface-range configuration mode, all command parameters that you enter are attributed to all interfaces within that range until you exit this mode.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    interface range {port-range | macro macro_name}

4.    end

5.    show interfaces [interface-id]

6.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

interface range {port-range | macro macro_name}

Example:

Switch(config)# interface range macro

Specifies the range of interfaces (VLANs or physical ports) to be configured, and enter interface-range configuration mode.

- You can use the interface range command to configure up to five port ranges or a previously defined macro.

- The macro variable is explained in the Configuring and Using Interface Range Macros.

- In a comma-separated port-range, you must enter the interface type for each entry and enter spaces before and after the comma.

- In a hyphen-separated port-range, you do not need to re-enter the interface type, but you must enter a space before the hyphen.

Note:
Use the normal configuration commands to apply the configuration parameters to all interfaces in the range. Each command is executed as it is entered.

Step 4

end

Example:

Switch(config)# end

Returns to privileged EXEC mode.

Step 5

show interfaces [interface-id]

Example:

Switch# show interfaces

Verifies the configuration of the interfaces in the range.

Step 6

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Configuring and Using Interface Range Macros

You can create an interface range macro to automatically select a range of interfaces for configuration. Before you can use the macro keyword in the interface range macro global configuration command string, you must use the define interface-range global configuration command to define the macro.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    define interface-range macro_name interface-range

4.    interface range macro macro_name

5.    end

6.    show running-config | include define

7.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

define interface-range macro_name interface-range

Example:

Switch(config)# define interface-range enet_list gigabitethernet1/0/1 - 2

Defines the interface-range macro, and save it in NVRAM.

- The macro_name is a 32-character maximum character string.

- A macro can contain up to five comma-separated interface ranges.

- Each interface-range must consist of the same port type.

Note:
Before you can use the macro keyword in the interface range macro global configuration command string, you must use the define interface-range global configuration command to define the macro.

Step 4

interface range macro macro_name

Example:

Switch(config)# interface range macro enet_list

Selects the interface range to be configured using the values saved in the interface-range macro called macro_name.

You can now use the normal configuration commands to apply the configuration to all interfaces in the defined macro.

Step 5

end

Example:

Switch(config)# end

Returns to privileged EXEC mode.

Step 6

show running-config | include define

Example:

Switch# show running-config | include define

Shows the defined interface range macro configuration.

Step 7

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Configuring Ethernet Interfaces

- Setting the Interface Speed and Duplex Parameters

Setting the Interface Speed and Duplex Parameters

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    interface interface-id

4.    speed {10 | 100 | 1000 | auto [10 | 100 | 1000] | nonegotiate}

5.    duplex {auto | full | half}

6.    end

7.    show interfaces interface-id

8.    copy running-config startup-config

9.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

interface interface-id

Example:

Switch(config)# interface gigabitethernet1/0/3

Specifies the physical interface to be configured, and enter interface configuration mode.

Step 4

speed {10 | 100 | 1000 | auto [10 | 100 | 1000] | nonegotiate}

Example:

Switch(config-if)# speed 10

This command is not available on a 10-Gigabit Ethernet interface.

Enter the appropriate speed parameter for the interface:

- Enter 10, 100, or 1000 to set a specific speed for the interface. The 1000 keyword is available only for 10/100/1000 Mb/s ports.

- Enter auto to enable the interface to autonegotiate speed with the connected device. If you use the 10, 100, or the 1000 keywords with the auto keyword, the port autonegotiates only at the specified speeds.

- The nonegotiate keyword is available only for SFP module ports. SFP module ports operate only at 1000 Mb/s but can be configured to not negotiate if connected to a device that does not support autonegotiation.

Step 5

duplex {auto | full | half}

Example:

Switch(config-if)# duplex half

This command is not available on a 10-Gigabit Ethernet interface.

Enter the duplex parameter for the interface.

Enable half-duplex mode (for interfaces operating only at 10 or 100 Mb/s). You cannot configure half-duplex mode for interfaces operating at 1000 Mb/s.

You can configure the duplex setting when the speed is set to auto.

Step 6

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Step 7

show interfaces interface-id

Example:

Switch# show interfaces gigabitethernet1/0/3

Displays the interface speed and duplex mode configuration.

Step 8

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Step 9

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Configuring IEEE 802.3x Flow Control

SUMMARY STEPS

1.    configure terminal

2.    interface interface-id

3.    flowcontrol {receive} {on | off | desired}

4.    end

5.    show interfaces interface-id

6.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode

Step 2

interface interface-id

Example:

Switch(config)# interface gigabitethernet1/0/1

Specifies the physical interface to be configured, and enter interface configuration mode.

Step 3

flowcontrol {receive} {on | off | desired}

Example:

Switch(config-if)# flowcontrol receive on

Configures the flow control mode for the port.

Step 4

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Step 5

show interfaces interface-id

Example:

Switch# show interfaces gigabitethernet1/0/1

Verifies the interface flow control settings.

Step 6

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Configuring Layer 3 Interfaces

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    interface {gigabitethernet interface-id} | {vlan vlan-id} | {port-channel port-channel-number}

4.    no switchport

5.    ip address ip_address subnet_mask

6.    no shutdown

7.    end

8.    show interfaces [interface-id]

9.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

interface {gigabitethernet interface-id} | {vlan vlan-id} | {port-channel port-channel-number}

Example:

Switch(config)# interface gigabitethernet1/0/2

Specifies the interface to be configured as a Layer 3 interface, and enter interface configuration mode.

Step 4

no switchport

Example:

Switch(config-if)# no switchport

For physical ports only, enters Layer 3 mode.

Step 5

ip address ip_address subnet_mask

Example:

Switch(config-if)# ip address 192.20.135.21 255.255.255.0

Configures the IP address and IP subnet.

Step 6

no shutdown

Example:

Switch(config-if)# no shutdown

Enables the interface.

Step 7

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Step 8

show interfaces [interface-id]

Verifies the configuration.

Step 9

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Configuring SVI Autostate Exclude

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    interface interface-id

4.    switchport autostate exclude

5.    end

6.    show running config interface interface-id

7.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

interface interface-id

Example:

Switch(config)# interface gigabitethernet1/0/2

Specifies a Layer 2 interface (physical port or port channel), and enter interface configuration mode.

Step 4

switchport autostate exclude

Example:

Switch(config-if)# switchport autostate exclude

Excludes the access or trunk port when defining the status of an SVI line state (up or down)

Step 5

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Step 6

show running config interface interface-id

(Optional) Shows the running configuration.

Verifies the configuration.

Step 7

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Shutting Down and Restarting the Interface

Shutting down an interface disables all functions on the specified interface and marks the interface as unavailable on all monitoring command displays. This information is communicated to other network servers through all dynamic routing protocols. The interface is not mentioned in any routing updates.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    interface {vlan vlan-id} | { gigabitethernetinterface-id} | {port-channel port-channel-number}

4.    shutdown

5.    no shutdown

6.    end

7.    show running-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

interface {vlan vlan-id} | { gigabitethernetinterface-id} | {port-channel port-channel-number}

Example:

Switch(config)# interface gigabitethernet1/0/2

Selects the interface to be configured.

Step 4

shutdown

Example:

Switch(config-if)# shutdown

Shuts down an interface.

Step 5

no shutdown

Example:

Switch(config-if)# no shutdown

Restarts an interface.

Step 6

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Step 7

show running-config

Example:

Switch# show running-config

Verifies your entries.

Configuring the Console Media Type

Follow these steps to set the console media type to RJ-45. If you configure the console as RJ-45, USB console operation is disabled, and input comes only through the RJ-45 connector.

This configuration applies to all switches in a stack.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    line console 0

4.    media-type rj45

5.    end

6.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters the global configuration mode.

Step 3

line console 0

Example:

Switch(config)# line console 0

Configures the console and enters line configuration mode.

Step 4

media-type rj45

Example:

Switch(config-line)# media-type rj45

Configures the console media type to be only RJ-45 port. If you do not enter this command and both types are connected, the USB port is used by default.

Step 5

end

Example:

Switch(config)# end

Returns to privileged EXEC mode.

Step 6

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Configuring the USB Inactivity Timeout

The configurable inactivity timeout reactivates the RJ-45 console port if the USB console port is activated but no input activity occurs on it for a specified time period. When the USB console port is deactivated due to a timeout, you can restore its operation by disconnecting and reconnecting the USB cable.

Note

The configured inactivity timeout applies to all switches in a stack. However, a timeout on one switch does not cause a timeout on other switches in the stack.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    line console 0

4.    usb-inactivity-timeout timeout-minutes

5.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters the global configuration mode.

Step 3

line console 0

Example:

Switch(config)# line console 0

Configures the console and enters line configuration mode.

Step 4

usb-inactivity-timeout timeout-minutes

Example:

Switch(config-line)# usb-inactivity-timeout 30

Specify an inactivity timeout for the console port. The range is 1 to 240 minutes. The default is to have no timeout configured.

Step 5

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Monitoring Interface Characteristics

- Monitoring Interface Status

- Clearing and Resetting Interfaces and Counters

Monitoring Interface Status

Commands entered at the privileged EXEC prompt display information about the interface, including the versions of the software and the hardware, the configuration, and statistics about the interfaces.

Show Commands for Interfaces

Command

Purpose

show interfaces interface-id status [err-disabled]

Displays interface status or a list of interfaces in the error-disabled state.

show interfaces [interface-id] switchport

Displays administrative and operational status of switching (nonrouting) ports. You can use this command to find out if a port is in routing or in switching mode.

show interfaces [interface-id] description

Displays the description configured on an interface or all interfaces and the interface status.

show ip interface [interface-id]

Displays the usability status of all interfaces configured for IP routing or the specified interface.

show interface [interface-id] stats

Displays the input and output packets by the switching path for the interface.

show interfaces interface-id

(Optional) Displays speed and duplex on the interface.

show interfaces transceiver dom-supported-list

(Optional) Displays Digital Optical Monitoring (DOM) status on the connect SFP modules.

show interfaces transceiver properties

(Optional) Displays temperature, voltage, or amount of current on the interface.

show interfaces [interface-id] [{transceiver properties | detail}] module number]

Displays physical and operational status about an SFP module.

show running-config interface [interface-id]

Displays the running configuration in RAM for the interface.

show version

Displays the hardware configuration, software version, the names and sources of configuration files, and the boot images.

show controllers ethernet-controller interface-id phy

Displays the operational state of the auto-MDIX feature on the interface.

Clearing and Resetting Interfaces and Counters

Clear Commands for Interfaces

Command

Purpose

clear counters [interface-id]

Clears interface counters.

clear interface interface-id

Resets the hardware logic on an interface.

clear line [number | console 0 | vty number]

Resets the hardware logic on an asynchronous serial line.

Note

The clear counters privileged EXEC command does not clear counters retrieved by using Simple Network Management Protocol (SNMP), but only those seen with the show interface privileged EXEC command.

Configuration Examples for Interface Characteristics

- Adding a Description to an Interface: Example

- Configuring a Range of Interfaces: Examples

- Configuring and Using Interface Range Macros: Examples

- Setting Interface Speed and Duplex Mode: Example

- Configuring Layer 3 Interfaces: Example

- Configuring the Console Media Type: Example

- Configuring the USB Inactivity Timeout: Example

Adding a Description to an Interface: Example

Switch# configure terminal
Enter configuration commands, one per line. End with CNTRL/Z.
Switch(config)# interface gigabitethernet1/0/2
Switch(config-if)# description Connects to Marketing
Switch(config-if)# end
Switch# show interfaces gigabitethernet1/0/2 description
Interface Status         Protocol Description
Gi1/0/2   admin down     down     Connects to Marketing

Configuring a Range of Interfaces: Examples

This example shows how to use the interface range global configuration command to set the speed to 100 Mb/s on ports 1 to 4 on switch 1:

Switch# configure terminal
Switch(config)# interface range gigabitethernet1/0/1 - 4
Switch(config-if-range)# speed 100

This example shows how to use a comma to add different interface type strings to the range to enable Gigabit Ethernet ports 1 to 3 and 10-Gigabit Ethernet ports 1 and 2 to receive flow-control pause frames:

Switch# configure terminal
Switch(config)# interface range gigabitethernet1/0/1 - 3 , tengigabitethernet1/0/1 - 2
Switch(config-if-range)# flowcontrol receive on

If you enter multiple configuration commands while you are in interface-range mode, each command is executed as it is entered. The commands are not batched and executed after you exit interface-range mode. If you exit interface-range configuration mode while the commands are being executed, some commands might not be executed on all interfaces in the range. Wait until the command prompt reappears before exiting interface-range configuration mode.

Configuring and Using Interface Range Macros: Examples

This example shows how to define an interface-range named enet_list to include ports 1 and 2 on switch 1 and to verify the macro configuration:

Switch# configure terminal
Switch(config)# define interface-range enet_list gigabitethernet1/0/1 - 2
Switch(config)# end
Switch# show running-config | include define
define interface-range enet_list GigabitEthernet1/0/1 - 2

This example shows how to create a multiple-interface macro named macro1:

Switch# configure terminal
Switch(config)# define interface-range macro1 gigabitethernet1/0/1 - 2, gigabitethernet1/0/5 - 7, tengigabitethernet1/0/1 -2
Switch(config)# end

This example shows how to enter interface-range configuration mode for the interface-range macro enet_list:

Switch# configure terminal
Switch(config)# interface range macro enet_list
Switch(config-if-range)#

This example shows how to delete the interface-range macro enet_list and to verify that it was deleted.

Switch# configure terminal
Switch(config)# no define interface-range enet_list
Switch(config)# end
Switch# show run | include define
Switch#

Setting Interface Speed and Duplex Mode: Example

This example shows how to set the interface speed to 100 Mb/s and the duplex mode to half on a 10/100/1000 Mb/s port:

Switch# configure terminal
Switch(config)# interface gigabitethernet1/0/3
Switch(config-if)# speed 10
Switch(config-if)# duplex half

This example shows how to set the interface speed to 100 Mb/s on a 10/100/1000 Mb/s port:

Switch# configure terminal
Switch(config)# interface gigabitethernet1/0/2
Switch(config-if)# speed 100

Configuring Layer 3 Interfaces: Example

Switch# configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Switch(config)# interface gigabitethernet1/0/2
Switch(config-if)# no switchport
Switch(config-if)# ip address 192.20.135.21 255.255.255.0
Switch(config-if)# no shutdown

Configuring the Console Media Type: Example

This example disables the USB console media type and enables the RJ-45 console media type.

Switch# configure terminal
Switch(config)# line console 0
Switch(config-line)# media-type rj45

This configuration terminates any active USB console media type in the stack. A log shows that this termination has occurred. This example shows that the console on switch 1 reverted to RJ-45.

*Mar  1 00:25:36.860: %USB_CONSOLE-6-CONFIG_DISABLE: Console media-type USB disabled by system configuration, media-type reverted to RJ45.

At this point no switches in the stack allow a USB console to have input. A log entry shows when a console cable is attached. If a USB console cable is connected to switch 2, it is prevented from providing input.

*Mar  1 00:34:27.498: %USB_CONSOLE-6-CONFIG_DISALLOW: Console media-type USB is disallowed by system configuration, media-type remains RJ45. (switch-stk-2)

This example reverses the previous configuration and immediately activates any USB console that is connected.

Switch# configure terminal
Switch(config)# line console 0
Switch(config-line)# no media-type rj45

Configuring the USB Inactivity Timeout: Example

This example configures the inactivity timeout to 30 minutes:

Switch# configure terminal
Switch(config)# line console 0
Switch(config-line)# usb-inactivity-timeout 30

To disable the configuration, use these commands:

Switch# configure terminal
Switch(config)# line console 0
Switch(config-line)# no usb-inactivity-timeout

If there is no (input) activity on a USB console port for the configured number of minutes, the inactivity timeout setting applies to the RJ-45 port, and a log shows this occurrence:

*Mar  1 00:47:25.625: %USB_CONSOLE-6-INACTIVITY_DISABLE: Console media-type USB disabled due to inactivity, media-type reverted to RJ45.

At this point, the only way to reactivate the USB console port is to disconnect and reconnect the cable.

When the USB cable on the switch has been disconnected and reconnected, a log similar to this appears:

*Mar  1 00:48:28.640: %USB_CONSOLE-6-MEDIA_USB: Console media-type is USB.

Additional References for the Interface Characteristics Feature

Related Documents

Related Topic

Document Title

Platform-independent command reference

Interface and Hardware Command Reference, Cisco IOS XE Release 3.2SE (Catalyst 3850 Switches)

Platform-independent configuration information

Interface and Hardware Component Configuration Guide, Cisco IOS XE Release 3SE (Catalyst 3850 Switches)

Error Message Decoder

Description

Link

To help you research and resolve system error messages in this release, use the Error Message Decoder tool.

Click Here

Standards and RFCs

Standard/RFC

Title

None

--

MIBs

MIB

MIBs Link

All supported MIBs for this release.

To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

Click Here

Technical Assistance

Description

Link

The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

Click Here

Feature History and Information for Configuring Interface Characteristics

Release

Modification

Cisco IOS XE 3.2SE

This feature was introduced.

Chapter 4. Configuring Auto-MDIX

- Prerequisites for Auto-MDIX

- Restrictions for Auto-MDIX

- Information about Configuring Auto-MDIX

- How to Configure Auto-MDIX

- Example for Configuring Auto-MDIX

- Additional References

- Feature History and Information for Auto-MDIX

Prerequisites for Auto-MDIX

To configure Layer 2 parameters, if the interface is in Layer 3 mode, you must enter the switchport interface configuration command without any parameters to put the interface into Layer 2 mode. This shuts down the interface and then re-enables it, which might generate messages on the device to which the interface is connected. When you put an interface that is in Layer 3 mode into Layer 2 mode, the previous configuration information related to the affected interface might be lost, and the interface is returned to its default configuration.

Automatic medium-dependent interface crossover (auto-MDIX) is enabled by default.

Auto-MDIX is supported on all 10/100/1000-Mb/s and on 10/100/1000BASE-TX small form-factor pluggable (SFP)-module interfaces. It is not supported on 1000BASE-SX or -LX SFP module interfaces.

Restrictions for Auto-MDIX

The switch might not support a pre-standard powered device—such as Cisco IP phones and access points that do not fully support IEEE 802.3af—if that powered device is connected to the switch through a crossover cable. This is regardless of whether auto-MIDX is enabled on the switch port.

Information about Configuring Auto-MDIX

- Auto-MDIX on an Interface

Auto-MDIX on an Interface

When automatic medium-dependent interface crossover (auto-MDIX) is enabled on an interface, the interface automatically detects the required cable connection type (straight through or crossover) and configures the connection appropriately. When connecting switches without the auto-MDIX feature, you must use straight-through cables to connect to devices such as servers, workstations, or routers and crossover cables to connect to other switches or repeaters. With auto-MDIX enabled, you can use either type of cable to connect to other devices, and the interface automatically corrects for any incorrect cabling. For more information about cabling requirements, see the hardware installation guide.

This table shows the link states that result from auto-MDIX settings and correct and incorrect cabling.

Link Conditions and Auto-MDIX Settings

Local Side Auto-MDIX

Remote Side Auto-MDIX

With Correct Cabling

With Incorrect Cabling

On

On

Link up

Link up

On

Off

Link up

Link up

Off

On

Link up

Link up

Off

Off

Link up

Link down

How to Configure Auto-MDIX

- Configuring Auto-MDIX on an Interface

Configuring Auto-MDIX on an Interface

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    interface interface-id

4.    speed auto

5.    duplex auto

6.    end

7.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode

Step 3

interface interface-id

Example:

Switch(config)# interface gigabitethernet1/0/1

Specifies the physical interface to be configured, and enter interface configuration mode.

Step 4

speed auto

Example:

Switch(config-if)# speed auto

Configures the interface to autonegotiate speed with the connected device.

Step 5

duplex auto

Example:

Switch(config-if)# duplex auto

Configures the interface to autonegotiate duplex mode with the connected device.

Step 6

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Step 7

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Example for Configuring Auto-MDIX

This example shows how to enable auto-MDIX on a port:

Switch# configure terminal
Switch(config)# interface gigabitethernet1/0/1
Switch(config-if)# speed auto
Switch(config-if)# duplex auto
Switch(config-if)# mdix auto
Switch(config-if)# end

Additional References

Error Message Decoder

Description

Link

To help you research and resolve system error messages in this release, use the Error Message Decoder tool.

Click Here

MIBs

MIB

MIBs Link

All supported MIBs for this release.

To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

Click Here

Technical Assistance

Description

Link

The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

Click Here

Feature History and Information for Auto-MDIX

Release

Modification

Cisco IOS XE 3.2SE

This feature was introduced.

Chapter 5. Configuring Ethernet Management Port

- Finding Feature Information

- Prerequisites for Ethernet Management Ports

- Information about the Ethernet Management Port

- How to Configure the Ethernet Management Port

- Additional References

- Feature Information for Ethernet Management Ports

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to Click Here . An account on Cisco.com is not required.

Prerequisites for Ethernet Management Ports

When connecting a PC to the Ethernet management port, you must first assign an IP address.

Information about the Ethernet Management Port

The Ethernet management port, also referred to as the Gi0/0 or GigabitEthernet0/0 port, is a VRF (VPN routing/forwarding) interface to which you can connect a PC. You can use the Ethernet management port instead of the switch console port for network management. When managing a switch stack, connect the PC to the Ethernet management port on a stack member.

- Ethernet Management Port Direct Connection to a Switch

- Ethernet Management Port Connection to Stack Switches using a Hub

- Ethernet Management Port and Routing

- Supported Features on the Ethernet Management Port

Ethernet Management Port Direct Connection to a Switch

Connecting a Switch to a PC. This figure displays how to connect the Ethernet management port to the PC for a switch or a standalone switch.

Ethernet Management Port Connection to Stack Switches using a Hub

In a stack with only stack switches, all the Ethernet management ports on the stack members are connected to a hub to which the PC is connected. The active link is from the Ethernet management port on the active switchstack masterthrough the hub, to the PC. If the activeswitch fails and a new active switch is elected, the active link is now from the Ethernet management port on the new active switch to the PC.

Connecting a Switch Stack to a PC. This figure displays how a PC uses a hub to connect to a switch stack.

1

Switch stack

3

Hub

2

Management port

4

PC

Ethernet Management Port and Routing

By default, the Ethernet management port is enabled. The switch cannot route packets from the Ethernet management port to a network port, and the reverse. Even though the Ethernet management port does not support routing, you may need to enable routing protocols on the port.

Network Example with Routing Protocols Enabled. Enable routing protocols on the Ethernet management port when the PC is multiple hops away from the switch and the packets must pass through multiple Layer 3 devices to reach the PC.

In the above figure , if the Ethernet management port and the network ports are associated with the same routing process, the routes are propagated as follows:

- The routes from the Ethernet management port are propagated through the network ports to the network.

- The routes from the network ports are propagated through the Ethernet management port to the network.

Because routing is not supported between the Ethernet management port and the network ports, traffic between these ports cannot be sent or received. If this happens, data packet loops occur between the ports, which disrupt the switch and network operation. To prevent the loops, configure route filters to avoid routes between the Ethernet management port and the network ports.

Supported Features on the Ethernet Management Port

The Ethernet management port supports these features:

- Express Setup (only in switch stacks)

- Network Assistant

- Telnet with passwords

- TFTP

- Secure Shell (SSH)

- DHCP-based autoconfiguration

- SMNP (only the ENTITY-MIB and the IF-MIB)

- IP ping

- Interface features

- Speed—10 Mb/s, 100 Mb/s, 1000 Mb/s, and autonegotiation

- Duplex mode—Full, half, and autonegotiation

- Loopback detection

- Cisco Discovery Protocol (CDP)

- DHCP relay agent

- IPv4 and IPv6 access control lists (ACLs)

- Routing protocols

Caution

Before enabling a feature on the Ethernet management port, make sure that the feature is supported. If you try to configure an unsupported feature on the Ethernet Management port, the feature might not work properly, and the switch might fail.

How to Configure the Ethernet Management Port

- Disabling and Enabling the Ethernet Management Port

Disabling and Enabling the Ethernet Management Port

SUMMARY STEPS

1.    configure terminal

2.    interface gigabitethernet0/0

3.    shutdown

4.    no shutdown

5.    exit

6.    show interfaces gigabitethernet0/0

DETAILED STEPS

Command or Action

Purpose

Step 1

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 2

interface gigabitethernet0/0

Example:

Switch(config)# interface gigabitethernet0/0

Specifies the Ethernet management port in the CLI.

Step 3

shutdown

Example:

Switch(config-if)# shutdown

Disables the Ethernet management port.

Step 4

no shutdown

Example:

Switch(config-if)# no shutdown

Enables the Ethernet management port.

Step 5

exit

Example:

Switch(config-if)# exit

Exits interface configuration mode.

Step 6

show interfaces gigabitethernet0/0

Example:

Switch# show interfaces gigabitethernet0/0

Displays the link status.

To find out the link status to the PC, you can monitor the LED for the Ethernet management port. The LED is green (on) when the link is active, and the LED is off when the link is down. The LED is amber when there is a POST failure.

What to Do Next

Proceed to manage or configure your switch using the Ethernet management port. Refer to the Network Management Configuration Guide (Catalyst 3850 Switches).

Additional References

Related Documents

Related Topic

Document Title

Bootloader configuration

System Management Configuration Guide (Catalyst 3850 Switches)

Bootloader commands

System Management Command Reference (Catalyst 3850 Switches)

Error Message Decoder

Description

Link

To help you research and resolve system error messages in this release, use the Error Message Decoder tool.

Click Here

MIBs

MIB

MIBs Link

All supported MIBs for this release.

To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

Click Here

Technical Assistance

Description

Link

The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

Click Here

Feature Information for Ethernet Management Ports

Release

Modification

Cisco IOS XE 3.2SE

This feature was introduced.

Chapter 6. Configuring LLDP, LLDP-MED, and Wired Location Service

- Finding Feature Information

- LLDP, LLDP-MED, and Wired Location Service Overview

- How to Configure LLDP, LLDP-MED, and Wired Location Service

- Configuration Examples for LLDP, LLDP-MED, and Wired Location Service

- Monitoring and Maintaining LLDP, LLDP-MED, and Wired Location Service

- Additional References for LLDP, LLDP-MED, and Wired Location Service

- Feature Information for LLDP, LLDP-MED, and Wired Location Service

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to Click Here . An account on Cisco.com is not required.

LLDP, LLDP-MED, and Wired Location Service Overview

- LLDP

- LLDP-MED

- Wired Location Service

- Default LLDP Configuration

- Restrictions for LLDP

LLDP

The Cisco Discovery Protocol (CDP) is a device discovery protocol that runs over Layer 2 (the data link layer) on all Cisco-manufactured devices (routers, bridges, access servers, switches, and controllers). CDP allows network management applications to automatically discover and learn about other Cisco devices connected to the network.

To support non-Cisco devices and to allow for interoperability between other devices, the switch supports the IEEE 802.1AB Link Layer Discovery Protocol (LLDP). LLDP is a neighbor discovery protocol that is used for network devices to advertise information about themselves to other devices on the network. This protocol runs over the data-link layer, which allows two systems running different network layer protocols to learn about each other.

- LLDP Supported TLVs

- LLDP and Cisco Switch Stacks

- LLDP and Cisco Medianet

LLDP Supported TLVs

LLDP supports a set of attributes that it uses to discover neighbor devices. These attributes contain type, length, and value descriptions and are referred to as TLVs. LLDP supported devices can use TLVs to receive and send information to their neighbors. This protocol can advertise details such as configuration information, device capabilities, and device identity.

The switch supports these basic management TLVs. These are mandatory LLDP TLVs.

- Port description TLV

- System name TLV

- System description TLV

- System capabilities TLV

- Management address TLV

These organizationally specific LLDP TLVs are also advertised to support LLDP-MED.

- Port VLAN ID TLV (IEEE 802.1 organizationally specific TLVs)

- MAC/PHY configuration/status TLV (IEEE 802.3 organizationally specific TLVs)

LLDP and Cisco Switch Stacks

A switch stack appears as a single switch in the network. Therefore, LLDP discovers the switch stack, not the individual stack members.

LLDP and Cisco Medianet

When you configure LLDP or CDP location information on a per-port basis, remote devices can send Cisco Medianet location information to the switch. For information, go to
Click Here

LLDP-MED

LLDP for Media Endpoint Devices (LLDP-MED) is an extension to LLDP that operates between endpoint devices such as IP phones and network devices such as switches. It specifically provides support for voice over IP (VoIP) applications and provides additional TLVs for capabilities discovery, network policy, Power over Ethernet, inventory management and location information. By default, all LLDP-MED TLVs are enabled.

- LLDP-MED Supported TLVs

LLDP-MED Supported TLVs

LLDP-MED supports these TLVs:

- LLDP-MED capabilities TLV

Allows LLDP-MED endpoints to determine the capabilities that the connected device supports and has enabled.

- Network policy TLV

Allows both network connectivity devices and endpoints to advertise VLAN configurations and associated Layer 2 and Layer 3 attributes for the specific application on that port. For example, the switch can notify a phone of the VLAN number that it should use. The phone can connect to any switch, obtain its VLAN number, and then start communicating with the call control.

By defining a network-policy profile TLV, you can create a profile for voice and voice-signaling by specifying the values for VLAN, class of service (CoS), differentiated services code point (DSCP), and tagging mode. These profile attributes are then maintained centrally on the switch and propagated to the phone.

- Power management TLV

Enables advanced power management between LLDP-MED endpoint and network connectivity devices. Allows switches and phones to convey power information, such as how the device is powered, power priority, and how much power the device needs.

LLDP-MED also supports an extended power TLV to advertise fine-grained power requirements, end-point power priority, and end-point and network connectivity-device power status. LLDP is enabled and power is applied to a port, the power TLV determines the actual power requirement of the endpoint device so that the system power budget can be adjusted accordingly. The switch processes the requests and either grants or denies power based on the current power budget. If the request is granted, the switch updates the power budget. If the request is denied, the switch turns off power to the port, generates a syslog message, and updates the power budget. If LLDP-MED is disabled or if the endpoint does not support the LLDP-MED power TLV, the initial allocation value is used throughout the duration of the connection.

You can change power settings by entering the power inline {auto [max max-wattage] | never | static [max max-wattage]} interface configuration command. By default the PoE interface is in auto mode; If no value is specified, the maximum is allowed (30 W).

- Inventory management TLV

Allows an endpoint to send detailed inventory information about itself to the switch, including information hardware revision, firmware version, software version, serial number, manufacturer name, model name, and asset ID TLV.

- Location TLV

Provides location information from the switch to the endpoint device. The location TLV can send this information:

- Civic location information

Provides the civic address information and postal information. Examples of civic location information are street address, road name, and postal community name information.

- ELIN location information

Provides the location information of a caller. The location is determined by the Emergency location identifier number (ELIN), which is a phone number that routes an emergency call to the local public safety answering point (PSAP) and which the PSAP can use to call back the emergency caller.

- Geographic location information

Provides the geographical details of a switch location such as latitude, longitude, and altitude of a switch.

- custom location

Provides customized name and value of a switch location.

Wired Location Service

The switch uses the location service feature to send location and attachment tracking information for its connected devices to a Cisco Mobility Services Engine (MSE). The tracked device can be a wireless endpoint, a wired endpoint, or a wired switch or controller. The switch notifies the MSE of device link up and link down events through the Network Mobility Services Protocol (NMSP) location and attachment notifications.

The MSE starts the NMSP connection to the switch, which opens a server port. When the MSE connects to the switch there are a set of message exchanges to establish version compatibility and service exchange information followed by location information synchronization. After connection, the switch periodically sends location and attachment notifications to the MSE. Any link up or link down events detected during an interval are aggregated and sent at the end of the interval.

When the switch determines the presence or absence of a device on a link-up or link-down event, it obtains the client-specific information such as the MAC address, IP address, and username. If the client is LLDP-MED- or CDP-capable, the switch obtains the serial number and UDI through the LLDP-MED location TLV or CDP.

Depending on the device capabilities, the switch obtains this client information at link up:

- Slot and port specified in port connection

- MAC address specified in the client MAC address

- IP address specified in port connection

- 802.1X username if applicable

- Device category is specified as a wired station

- State is specified as new

- Serial number, UDI

- Model number

- Time in seconds since the switch detected the association

Depending on the device capabilities, the switch obtains this client information at link down:

- Slot and port that was disconnected

- MAC address

- IP address

- 802.1X username if applicable

- Device category is specified as a wired station

- State is specified as delete

- Serial number, UDI

- Time in seconds since the switch detected the disassociation

When the switch shuts down, it sends an attachment notification with the state delete and the IP address before closing the NMSP connection to the MSE. The MSE interprets this notification as disassociation for all the wired clients associated with the switch.

If you change a location address on the switch, the switch sends an NMSP location notification message that identifies the affected ports and the changed address information.

Default LLDP Configuration

Default LLDP Configuration

Feature

Default Setting

LLDP global state

Disabled

LLDP holdtime (before discarding)

120 seconds

LLDP timer (packet update frequency)

30 seconds

LLDP reinitialization delay

2 seconds

LLDP tlv-select

Disabled to send and receive all TLVs

LLDP interface state

Disabled

LLDP receive

Disabled

LLDP transmit

Disabled

LLDP med-tlv-select

Disabled to send all LLDP-MED TLVs. When LLDP is globally enabled, LLDP-MED-TLV is also enabled.

Restrictions for LLDP

- If the interface is configured as a tunnel port, LLDP is automatically disabled.

- If you first configure a network-policy profile on an interface, you cannot apply the switchport voice vlan command on the interface. If the switchport voice vlan vlan-id is already configured on an interface, you can apply a network-policy profile on the interface. This way the interface has the voice or voice-signaling VLAN network-policy profile applied on the interface.

- You cannot configure static secure MAC addresses on an interface that has a network-policy profile.

How to Configure LLDP, LLDP-MED, and Wired Location Service

- Enabling LLDP

- Configuring LLDP Characteristics

- Configuring LLDP-MED TLVs

- Configuring Network-Policy TLV

- Configuring Location TLV and Wired Location Service

Enabling LLDP

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    lldp run

4.    interface interface-id

5.    lldp transmit

6.    lldp receive

7.    end

8.    show lldp

9.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

lldp run

Example:

Switch (config)# lldp run

Enables LLDP globally on the switch.

Step 4

interface interface-id

Example:

Switch (config)# interface
gigabitethernet2/0/1

Specifies the interface on which you are enabling LLDP, and enter interface configuration mode.

Step 5

lldp transmit

Example:

Switch(config-if)# lldp transmit

Enables the interface to send LLDP packets.

Step 6

lldp receive

Example:

Switch(config-if)# lldp receive

Enables the interface to receive LLDP packets.

Step 7

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Step 8

show lldp

Example:

Switch# show lldp

Verifies the configuration.

Step 9

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Configuring LLDP Characteristics

You can configure the frequency of LLDP updates, the amount of time to hold the information before discarding it, and the initialization delay time. You can also select the LLDP and LLDP-MED TLVs to send and receive.

Note

Steps 2 through 5 are optional and can be performed in any order.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    lldp holdtime seconds

4.    lldp reinit delay

5.    lldp timer rate

6.    lldp tlv-select

7.    interface interface-id

8.    lldp med-tlv-select

9.    end

10.    show lldp

11.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

lldp holdtime seconds

Example:

Switch(config)# lldp holdtime 120

(Optional) Specifies the amount of time a receiving device should hold the information from your device before discarding it.

The range is 0 to 65535 seconds; the default is 120 seconds.

Step 4

lldp reinit delay

Example:

Switch(config)# lldp reinit 2

(Optional) Specifies the delay time in seconds for LLDP to initialize on an interface.

The range is 2 to 5 seconds; the default is 2 seconds.

Step 5

lldp timer rate

Example:

Switch(config)# lldp timer 30

(Optional) Sets the sending frequency of LLDP updates in seconds.

The range is 5 to 65534 seconds; the default is 30 seconds.

Step 6

lldp tlv-select

Example:

Switch(config)# tlv-select

(Optional) Specifies the LLDP TLVs to send or receive.

Step 7

interface interface-id

Example:

Switch (config)# interface
gigabitethernet2/0/1

Specifies the interface on which you are enabling LLDP, and enter interface configuration mode.

Step 8

lldp med-tlv-select

Example:

Switch (config-if)# lldp
med-tlv-select inventory management

(Optional) Specifies the LLDP-MED TLVs to send or receive.

Step 9

end

Example:

Switch (config-if)# end

Returns to privileged EXEC mode.

Step 10

show lldp

Example:

Switch# show lldp

Verifies the configuration.

Step 11

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Configuring LLDP-MED TLVs

By default, the switch only sends LLDP packets until it receives LLDP-MED packets from the end device. It then sends LLDP packets with MED TLVs, as well. When the LLDP-MED entry has been aged out, it again only sends LLDP packets.

By using the lldp interface configuration command, you can configure the interface not to send the TLVs listed in the following table.

LLDP-MED TLVs

LLDP-MED TLV

Description

inventory-management

LLDP-MED inventory management TLV

location

LLDP-MED location TLV

network-policy

LLDP-MED network policy TLV

power-management

LLDP-MED power management TLV

Follow these steps to enable a TLV on an interface:

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    interface interface-id

4.    lldp med-tlv-select

5.    end

6.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

interface interface-id

Example:

Switch (config)# interface
gigabitethernet2/0/1

Specifies the interface on which you are enabling LLDP, and enter interface configuration mode.

Step 4

lldp med-tlv-select

Example:

Switch(config-if)# lldp med-tlv-select
inventory management

Specifies the TLV to enable.

Step 5

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Step 6

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Configuring Network-Policy TLV

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    network-policy profile profile number

4.    {voice | voice-signaling} vlan [vlan-id {cos cvalue | dscp dvalue}] | [[dot1p {cos cvalue | dscp dvalue}] | none | untagged]

5.    exit

6.    interface interface-id

7.    network-policy profile number

8.    lldp med-tlv-select network-policy

9.    end

10.    show network-policy profile

11.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

network-policy profile profile number

Example:

Switch(config)# network-policy profile 1

Specifies the network-policy profile number, and enter network-policy configuration mode. The range is 1 to 4294967295.

Step 4

{voice | voice-signaling} vlan [vlan-id {cos cvalue | dscp dvalue}] | [[dot1p {cos cvalue | dscp dvalue}] | none | untagged]

Example:

Switch(config-network-policy)# voice vlan 100 cos 4

Configures the policy attributes:

- voice—Specifies the voice application type.

- voice-signaling—Specifies the voice-signaling application type.

- vlan—Specifies the native VLAN for voice traffic.

- vlan-id—(Optional) Specifies the VLAN for voice traffic. The range is 1 to 4094.

- cos cvalue—(Optional) Specifies the Layer 2 priority class of service (CoS) for the configured VLAN. The range is 0 to 7; the default is 5.

- dscp dvalue—(Optional) Specifies the differentiated services code point (DSCP) value for the configured VLAN. The range is 0 to 63; the default is 46.

- dot1p—(Optional) Configures the telephone to use IEEE 802.1p priority tagging and use VLAN 0 (the native VLAN).

- none—(Optional) Do not instruct the IP telephone about the voice VLAN. The telephone uses the configuration from the telephone key pad.

- untagged—(Optional) Configures the telephone to send untagged voice traffic. This is the default for the telephone.

- untagged—(Optional) Configures the telephone to send untagged voice traffic. This is the default for the telephone.

Step 5

exit

Example:

Switch(config)# exit

Returns to global configuration mode.

Step 6

interface interface-id

Example:

Switch (config)# interface gigabitethernet2/0/1

Specifies the interface on which you are configuring a network-policy profile, and enter interface configuration mode.

Step 7

network-policy profile number

Example:

Switch(config-if)# network-policy 1

Specifies the network-policy profile number.

Step 8

lldp med-tlv-select network-policy

Example:

Switch(config-if)# lldp med-tlv-select network-policy

Specifies the network-policy TLV.

Step 9

end

Example:

Switch(config)# end

Returns to privileged EXEC mode.

Step 10

show network-policy profile

Example:

Switch# show network-policy profile

Verifies the configuration.

Step 11

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Configuring Location TLV and Wired Location Service

Beginning in privileged EXEC mode, follow these steps to configure location information for an endpoint and to apply it to an interface.

SUMMARY STEPS

1.    configure terminal

2.    location {admin-tag string | civic-location identifier {id | host} | elin-location string identifier id | custom-location identifier {id | host} | geo-location identifier {id | host}}

3.    exit

4.    interface interface-id

5.    location {additional-location-information word | civic-location-id {id | host} | elin-location-id id | custom-location-id {id | host} | geo-location-id {id | host} }

6.    end

7.    Use one of the following:

- show location admin-tag string

- show location civic-location identifier id

- show location elin-location identifier id

8.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 2

location {admin-tag string | civic-location identifier {id | host} | elin-location string identifier id | custom-location identifier {id | host} | geo-location identifier {id | host}}

Example:

Switch(config)# location civic-location identifier 1

Switch(config-civic)# number 3550

Switch(config-civic)# primary-road-name "Cisco Way"

Switch(config-civic)# city "San Jose"

Switch(config-civic)# state CA

Switch(config-civic)# building 19

Switch(config-civic)# room C6

Switch(config-civic)# county "Santa Clara"

Switch(config-civic)# country US

Specifies the location information for an endpoint.

- admin-tag—Specifies an administrative tag or site information.

- civic-location—Specifies civic location information.

- elin-location—Specifies emergency location information (ELIN).

- custom-location—Specifies custom location information.

- geo-location—Specifies geo-spatial location information.

- identifier id—Specifies the ID for the civic, ELIN, custom, or geo location.

- host—Specifies the host civic, custom, or geo location.

- string—Specifies the site or location information in alphanumeric format.

Step 3

exit

Example:

Switch(config-civic)# exit

Returns to global configuration mode.

Step 4

interface interface-id

Example:

Switch (config)# interface gigabitethernet2/0/1

Specifies the interface on which you are configuring the location information, and enter interface configuration mode.

Step 5

location {additional-location-information word | civic-location-id {id | host} | elin-location-id id | custom-location-id {id | host} | geo-location-id {id | host} }

Example:

Switch(config-if)# location elin-location-id 1

Enters location information for an interface:

- additional-location-information—Specifies additional information for a location or place.

- civic-location-id—Specifies global civic location information for an interface.

- elin-location-id—Specifies emergency location information for an interface.

- custom-location-id—Specifies custom location information for an interface.

- geo-location-id—Specifies geo-spatial location information for an interface.

- host—Specifies the host location identifier.

- word—Specifies a word or phrase with additional location information.

- id—Specifies the ID for the civic, ELIN, custom, or geo location. The ID range is 1 to 4095.

Step 6

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Step 7

Use one of the following:

- show location admin-tag string

- show location civic-location identifier id

- show location elin-location identifier id

Example:

Switch# show location admin-tag

or

Switch# show location civic-location
identifier

or

Switch# show location elin-location
identifier

Verifies the configuration.

Step 8

copy running-config startup-config

Example:

Switch# copy running-config
startup-config

(Optional) Saves your entries in the configuration file.

- Enabling Wired Location Service on the Switch

Enabling Wired Location Service on the Switch

Before You Begin

For wired location to function, you must first enter the ip device tracking global configuration command.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    nmsp notification interval {attachment | location} interval-seconds

4.    end

5.    show network-policy profile

6.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

nmsp notification interval {attachment | location} interval-seconds

Example:

Switch(config)# nmsp notification interval location 10

Specifies the NMSP notification interval.

attachment—Specifies the attachment notification interval.

location—Specifies the location notification interval.

interval-seconds—Duration in seconds before the switch sends the MSE the location or attachment updates. The range is 1 to 30; the default is 30.

Step 4

end

Example:

Switch(config)# end

Returns to privileged EXEC mode.

Step 5

show network-policy profile

Example:

Switch# show network-policy profile

Verifies the configuration.

Step 6

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Configuration Examples for LLDP, LLDP-MED, and Wired Location Service

- Configuring Network-Policy TLV: Examples

Configuring Network-Policy TLV: Examples

This example shows how to configure VLAN 100 for voice application with CoS and to enable the network-policy profile and network-policy TLV on an interface:

Switch# configure terminal
Switch(config)# network-policy 1
Switch(config-network-policy)# voice vlan 100 cos 4
Switch(config-network-policy)# exit
Switch(config)# interface gigabitethernet1/0/1
Switch(config-if)# network-policy profile 1
Switch(config-if)# lldp med-tlv-select network-policy

This example shows how to configure the voice application type for the native VLAN with priority tagging:

Switchconfig-network-policy)# voice vlan dot1p cos 4
Switchconfig-network-policy)# voice vlan dot1p dscp 34

Monitoring and Maintaining LLDP, LLDP-MED, and Wired Location Service

Commands for monitoring and maintaining LLDP, LLDP-MED, and wired location service.

Command

Description

clear lldp counters

Resets the traffic counters to zero.

clear lldp table

Deletes the LLDP neighbor information table.

clear nmsp statistics

Clears the NMSP statistic counters.

show lldp

Displays global information, such as frequency of transmissions, the holdtime for packets being sent, and the delay time before LLDP initializes on an interface.

show lldp entry entry-name

Displays information about a specific neighbor.

You can enter an asterisk (*) to display all neighbors, or you can enter the neighbor name.

show lldp interface [interface-id]

Displays information about interfaces with LLDP enabled.

You can limit the display to a specific interface.

show lldp neighbors [interface-id] [detail]

Displays information about neighbors, including device type, interface type and number, holdtime settings, capabilities, and port ID.

You can limit the display to neighbors of a specific interface or expand the display for more detailed information.

show lldp traffic

Displays LLDP counters, including the number of packets sent and received, number of packets discarded, and number of unrecognized TLVs.

show location admin-tag string

Displays the location information for the specified administrative tag or site.

show location civic-location identifier id

Displays the location information for a specific global civic location.

show location elin-location identifier id

Displays the location information for an emergency location

show network-policy profile

Displays the configured network-policy profiles.

show nmsp

Displays the NMSP information

Additional References for LLDP, LLDP-MED, and Wired Location Service

Error Message Decoder

Description

Link

To help you research and resolve system error messages in this release, use the Error Message Decoder tool.

Click Here

MIBs

MIB

MIBs Link

All supported MIBs for this release.

To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

Click Here

Technical Assistance

Description

Link

The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

Click Here

Feature Information for LLDP, LLDP-MED, and Wired Location Service

Release

Modification

Cisco IOS XE 3.2SE

This feature was introduced.

Chapter 7. Configuring System MTU

- Finding Feature Information

- Information about the MTU

- How to Configure MTU Sizes

- Configuration Examples for System MTU

- Additional References for System MTU

- Feature Information for System MTU

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to Click Here . An account on Cisco.com is not required.

Information about the MTU

The default maximum transmission unit (MTU) size for frames received and sent on all switch interfaces is 1500 bytes.

- Restrictions for System MTU

- System MTU Value Application

Restrictions for System MTU

When configuring the system MTU values, follow these guidelines:

- The switch does not support the MTU on a per-interface basis.

- If you enter the system mtu bytes global configuration command, the command does not take effect on the switch. This command only affects the system MTU size on Fast Ethernet switch ports.

System MTU Value Application

This table shows how the MTU values are applied.

MTU Values

Configuration

system mtu command

ip mtu command

ipv6 mtu command

Standalone switch or switch stack

You can enter the system mtu command on a switch or switch stack, but system MTU value does not take effect.

The range is from 1500 to 9198 bytes.

Use the ip mtu bytes command.

The range is from 68 up to the system MTU value (in bytes).
Note:
The IP MTU value is the applied value, not the configured value.

Use the ipv6 mtu bytes command.

The range is from 1280 to the system jumbo MTU value (in bytes).
Note:
The IPv6 MTU value is the applied value, not the configured value.

The upper limit of the IP or IPv6 MTU value is based on the switch or switch stack configuration and refers to the currently applied system MTU value. For more information about setting the MTU sizes, see the system mtu global configuration command in the command reference for this release.

How to Configure MTU Sizes

- Configuring the System MTU

- Configuring Protocol-Specific MTU

Configuring the System MTU

Follow these steps to change the MTU size for switched packets:

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    system mtu bytes

4.    end

5.    copy running-config startup-config

6.    show system mtu

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

system mtu bytes

Example:

Switch(config)# system mtu 1900

(Optional) Changes the MTU size for all Gigabit Ethernet and 10-Gigabit Ethernet interfaces.

Step 4

end

Example:

Switch(config)#  end

Returns to privileged EXEC mode.

Step 5

copy running-config startup-config

Example:

Switch# copy running-config startup-config

Saves your entries in the configuration file.

Step 6

show system mtu

Example:

Switch# show system mtu

Verifies your settings.

Configuring Protocol-Specific MTU

Beginning in privileged EXEC mode, follow these steps to change the MTU size for routed ports:

SUMMARY STEPS

1.    configure terminal

2.    interface interface

3.    ip mtu bytes

4.    ipv6 mtu bytes

5.    end

6.    copy running-config startup-config

7.    show system mtu

DETAILED STEPS

Command or Action

Purpose

Step 1

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 2

interface interface

Example:

Switch(config)# interface gigabitethernet0/0

Enters interface configuration mode.

Step 3

ip mtu bytes

Example:

Switch(config-if)# ip mtu 68

Changes the IPv4 MTU size

Step 4

ipv6 mtu bytes

Example:

Switch(config-if)# ipv6 mtu 1280

(Optional) Changes the IPv6 MTU size.

Step 5

end

Example:

Switch(config-if)#  end

Returns to privileged EXEC mode.

Step 6

copy running-config startup-config

Example:

Switch# copy running-config startup-config

Saves your entries in the configuration file.

Step 7

show system mtu

Example:

Switch# show system mtu

Verifies your settings.

Configuration Examples for System MTU

This example shows how to set the maximum packet size for a Gigabit Ethernet port to 7500 bytes:

Switch(config)# system mtu 7500
Switch(config)#
Switch(config)# exit

If you enter a value that is outside the allowed range for the specific type of interface, the value is not accepted. This example shows the response when you try to set Gigabit Ethernet interfaces to an out-of-range number:

Switch(config)# system mtu 25000
^
% Invalid input detected at '^' marker.

This is an example of output from the show system mtu command:

Switch# show system mtu
Global Ethernet MTU is 1500 bytes.

Additional References for System MTU

Error Message Decoder

Description

Link

To help you research and resolve system error messages in this release, use the Error Message Decoder tool.

Click Here

MIBs

MIB

MIBs Link

All supported MIBs for this release.

To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

Click Here

Technical Assistance

Description

Link

The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

Click Here

Feature Information for System MTU

Release

Modification

Cisco IOS XE 3.2SE

This feature was introduced.

Chapter 8. Configuring Internal Power Supplies

- Information About Internal Power Supplies

- How to Configure Internal Power Supplies

- Monitoring Internal Power Supplies

- Configuration Examples for Internal Power Supplies

- Additional References

- Feature History and Information for Internal Power Supplies

Information About Internal Power Supplies

See the switch installation guide for information about the power supplies.

How to Configure Internal Power Supplies

- Configuring Internal Power Supply

Configuring Internal Power Supply

You can use the power supply EXEC command to configure and manage the internal power supply on the switch. The switch does not support the no power supply EXEC command.

Follow these steps beginning in user EXEC mode:

SUMMARY STEPS

1.    power supply switch_number slot{A | B} { off | on }

2.    show environment power

DETAILED STEPS

Command or Action

Purpose

Step 1

power supply switch_number slot{A | B} { off | on }

Example:

Switch# power supply 1 slot A on

Sets the specified power supply to off or on by using one of these keywords:

- A —Selects the power supply in slot A.

- B —Selects power supply in slot B.

Note:
Power supply slot B is the closest to the outer edge of the switch.

- off —Set the power supply off.

- on —Set the power supply on.

By default, the switch power supply is on.

Step 2

show environment power

Example:

Switch# show environment power

Verifies your settings.

Monitoring Internal Power Supplies

Show Commands for Power Supplies

Command

Purpose

show environment power [ all | switch switch_number ]

(Optional) Displays the status of the internal power supplies for each switch in the stack or for the specified switch. The range is 1 to 9, depending on the switch member numbers in the stack.

Configuration Examples for Internal Power Supplies

This example shows how to set the power supply in slot A to off:

Switch# power supply 1 slot A off
Disabling Power supply A may result in a power loss to PoE devices and/or switches ... Continue? (yes/[no]): yes
Switch#
Jun 10 04:52:54.389: %PLATFORM_ENV-6-FRU_PS_OIR: FRU Power Supply 1 powered off
Jun 10 04:52:56.717: %PLATFORM_ENV-1-FAN_NOT_PRESENT: Fan is not present
Switch#

This example shows how to set the power supply in slot A to on:

Switch# power supply 1 slot A on
Jun 10 04:54:39.600: %PLATFORM_ENV-6-FRU_PS_OIR: FRU Power Supply 1 powered on

This example shows the output of the show env power command:

Switch# show env power

SW  PID                 Serial#     Status           Sys Pwr  PoE Pwr  Watts
--- ------------------  ----------  ---------------  -------  -------  -----
1A  PWR-C1-715WAC       LIT161010UE  OK              Good     Good     715
1B  Not Present

Switch#

show env power Status Descriptions

Field

Description

OK

The power supply is present and power is good.

Not Present

No power supply is installed.

No Input Power

The power supply is present but there is no input power.

Disabled

The power supply and input power are present, but power supply is switched off by CLI.

Not Responding

The power supply is not recognizable or is faulty.

Failure-Fan

The power supply fan is faulty.

Additional References

Error Message Decoder

Description

Link

To help you research and resolve system error messages in this release, use the Error Message Decoder tool.

Click Here

MIBs

MIB

MIBs Link

All supported MIBs for this release.

To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

Click Here

Technical Assistance

Description

Link

The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

Click Here

Feature History and Information for Internal Power Supplies

Release

Modification

Cisco IOS XE 3.2SE

This feature was introduced.

Cisco IOS XE 3.3SE

The slot keyword replaced the frufep keyword.

Chapter 9. Configuring Stack Power

- Finding Feature Information

- Prerequisites for StackPower

- Information About StackPower

- How to Configure StackPower

- Configuration Examples for Stack Power

- Where to Go Next

- Additional References for StackPower

- Feature History and Information for StackPower

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to Click Here . An account on Cisco.com is not required.

Prerequisites for StackPower

StackPower uses these terms:

- Available power is the total power available for PoE from all power supplies in the power stack. To see the available power in a stack, enter the show power inline privileged EXEC command.

- Budgeted power is the power allocated to all powered devices connected to PoE ports in the stack. Budgeted power is referred to as Used (Watts) in the output of the show power inline command.

- Consumed power is the actual power consumed by the powered devices. Consumed power is typically less that the budgeted power. To see the consumed power in a stack, enter the show power inline police privileged EXEC command.

Information About StackPower

- Power Supplies for the Stacking Switch

- StackPower Modes

- Power Priority

- Load Shedding

Power Supplies for the Stacking Switch

The switch has two power supplies per system, allowing the power load to be split between them. This accommodates the increased maximum power of 30 watts per port provided to a powered device to meet the PoE+ standard (802.3at). With PoE+, a 48-port system would need 1440 Watts to provide 30 Watts per powered device for the PoE ports. Systems with fewer powered devices might require only one power supply. In this case, the additional power supply can provide one-to-one redundancy for the active supply.

In addition, the stacking switch supports StackPower, which allows the power supplies to share the load across multiple systems in a stack. By connecting the switches with power stack cables, you can manage the power supplies of up to four stack members as a one large power supply that provides power to all switches and to the powered devices connected to switch ports. Since power supplies are most effective when running at 30 to 90% of their maximum load, taking some of the power supplies offline provides maximum power efficiency. Switches in a power stack must be members of the same switch (data) stack.

StackPower Modes

You can configure the power stack to run in one of two modes:

- In power-sharing mode (the default), all input power is available to be used for power loads. The total available power in all switches in the power stack (up to four) is treated as a single large power supply, with power available to all switches and to all powered devices connected to PoE ports. In this mode, the total available power is used for power budgeting decisions and no power is reserved to accommodate power-supply failures. If a power supply fails, powered devices and switches could be shut down (load shedding).

- In redundant mode, the power from the largest power supply in the system is subtracted from the power budget, which reduces the total available power, but provides backup power in case of a power-supply failure. Although there is less available power in the pool for switches and powered devices to draw from, the possibility of having to shut down switches or powered devices in case of a power failure or extreme power load is reduced.

In addition, you can configure the mode to run a strict power budget or a non-strict (relaxed) power budget. In both modes, power is denied when there is no more power available in the power budget.

- In strict mode, when a power supply fails and the available power drops below the budgeted power, the system balances the budget through load shedding of powered devices, even if the actual power being consumed is less than the available power.

- In non-strict mode, the power stack is allowed to run in an over-allocated state and is stable as long as the actual power does not exceed the available power. In this mode, a powered device drawing more than normal power could cause the power stack to start shedding loads. This is normally not a problem because most devices do not run at full power and the chances of multiple powered devices in the stack requiring maximum power at the same time is small.

You configure power modes at a power-stack level (that is, the mode is the same for all switches in the power stack).

You can also configure a switch connected in a power stack to not participate in the power stack by setting the switch to standalone power mode. This mode shuts down both stack power ports.

Power Priority

You can configure the priority of a switch or powered device to receive power. This priority determines the order in which devices are shut down in case of a power shortage. You can configure three priorities per system: the system (or switch) priority, the priority of the high-priority PoE ports on a switch, and the priority of the low-priority PoE ports on a switch.

You set port priority at the interface level for powered devices connected to a PoE port. By default, all ports are low priority.

You configure the priority values of each switch in the power stack and of all high and low priority ports on that switch to set the order in which switches and ports are shut down when power is lost and load shedding must occur. Priority values are from 1 to 27; switches and ports with highest values are shut down first.

Note

The 27 priorities are used to accommodate power stacks connected in a star configuration with the expandable power supply. In this configuration, there would be nine members (switches) per system with three priorities per switch.

On any switch, the switch priority must be lower than port priorities. and the high priority value must be set lower than the low priority value. We recommend that you configure different priority values for each switch and for its high priority ports and low priority ports. This limits the number of devices shut down at one time during a loss of power. If you try to configure the same priority value on different switches in a power stack, the configuration is allowed, but you receive a warning message.

The default priority ranges, if none are configured, are 1-9 for switches, 10-18 for high-priority ports, and 19-27 for low-priority ports.

Load Shedding

Load shedding is the process of shutting down devices in case of power supply, cable, or system failures. For power stacks in power-sharing mode, there are two types of load-shedding: immediate and graceful.

- Immediate load shed occurs when a failure could cause the power stack to fail very quickly. For example, if the largest power supply in the power stack fails, this could cause the stack to immediately start shutting down powered devices.

- Graceful load-shedding can occur when a smaller power supply fails. Switches and powered devices are shut down in order of their configured priority, starting with devices with priority 27, until the power budget matches the input power.

Graceful load shedding is always enabled and immediate load shedding occurs only when necessary, so both can occur at the same time.

Note

Load shedding does not occur in redundant mode unless two or more power supplies fail, because the largest power supply is used as a backup power source.

Notes on load shedding:

- The method (immediate or graceful) is not user-configurable, but is based on the power budget.

- Immediate load shedding also occurs in the order of configured priority, but occurs very quickly to prevent hardware damage caused by loss of power.

- If a switch is shut down because of load shedding, the output of the show stack-power privileged EXEC command still includes the MAC address of the shut down switch as a neighbor switch, even though the switch is down. This command output shows the StackPower topology, even if there is not enough power to power up a switch.

How to Configure StackPower

Configuring stack power includes these tasks:

- Configuring PowerStack Parameters

- Configuring PowerStack Switch Power Parameters

- Configuring PoE Port Priority

Configuring PowerStack Parameters

SUMMARY STEPS

1.    configure terminal

2.    stack-power stack power stack name

3.    mode {power-sharing | redundant} [strict]

4.    end

5.    show stack-power

DETAILED STEPS

Command or Action

Purpose

Step 1

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 2

stack-power stack power stack name

Example:

Switch(config)# stack-power stack power 1

Enters the stack power stack name and enter power stack configuration mode. The name can be up to 31 characters.

Step 3

mode {power-sharing | redundant} [strict]

Example:

Switch(config-stackpower)# mode redundant

Sets the operating mode for the power stack:

- power-sharing—The input power from all switches in the power stack can be used for loads, and the total available power appears as one huge power supply. This is the default.

- redundant—The largest power supply is removed from the power pool to be used as backup power in case one of the other power supplies fails. This is the recommended mode if enough power is available in the system.

- strict—(Optional) Configures the power stack mode to run a strict power budget. The stack power needs cannot exceed the available power. The default is non-strict.

Step 4

end

Example:

Switch(config-stackpower)# end

Returns to privileged EXEC mode.

Step 5

show stack-power

Example:

Switch# show stack-power

Verifies your entries.

Configuring PowerStack Switch Power Parameters

SUMMARY STEPS

1.    configure terminal

2.    stack-power switch switch-number

3.    stack [power-stack-name]

4.    power-priority switch value

5.    power-priority high value

6.    power-priority low value

7.    end

8.    show stack-power

DETAILED STEPS

Command or Action

Purpose

Step 1

configure terminal

Example:

Switch# configure terminal

Step 2

stack-power switch switch-number

Example:

Switch(config)# stack-power switch 4

Enters global configuration mode.

Enters switch stack power configuration mode for the stack member switch number. The range is from 1 to 9.

Note:
Only four switches can belong to the same power stack.

Step 3

stack [power-stack-name]

Example:

Switch(config-switch-stackpower)# stack power2

Enters the name of the power stack to which the switch belongs. The name can be up to 31 characters. If you do not enter a name and no other switches in the power stack have a name configured, a power-stack name is automatically generated.

Step 4

power-priority switch value

Example:

Switch(config-switch-stackpower)# power-priority switch 5

Sets the power priority of the switch. The range is from 1 to 27. This value must be lower than the value set for the low and high-priority ports.

Step 5

power-priority high value

Example:

Switch(config-switch-stackpower)# power-priority high 12

Sets the power priority of the PoE ports on the switch that are configured as high-priority ports. The range is from 1 to 27, with 1 as the highest priority. The high value must be lower than the value set for the low-priority ports and higher than the value set for the switch.

Step 6

power-priority low value

Example:

Switch(config-switch-stackpower)# power-priority low 20

Sets the power priority of the PoE ports on the switch that are configured as low-priority ports. The range is from 1 to 27. This value must be higher than the value set for the high-priority ports and the value set for the switch.

Step 7

end

Example:

Switch(config-switch-stackpower)# end

Returns to privileged EXEC mode.

Step 8

show stack-power

Example:

Switch# show stack-power

Verifies your entries.

Configuring PoE Port Priority

SUMMARY STEPS

1.    configure terminal

2.    interface interface-id

3.    power inline port priority {high | low}

4.    end

5.    show power inline priority

DETAILED STEPS

Command or Action

Purpose

Step 1

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 2

interface interface-id

Example:

Switch(config)# interface gigabitethernet 1/0/1

Enters the interface ID of the port in the stack and enters interface configuration mode. The interface must be a PoE port.

Step 3

power inline port priority {high | low}

Example:

Switch(config-if)# power inline port priority high

Sets the power priority of the port to high or low. Powered devices connected to low priority ports are shut down first in case of a power reduction. The default is low priority.

Note:
Although the power inline port priority {high | low} command is visible on the nonstacking switch PoE ports, it has no effect because these switches do not participate in stack power.

Step 4

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Step 5

show power inline priority

Example:

Switch# show power inline priority

Verifies your entries.

Configuration Examples for Stack Power

- Immediate Load Shedding: Examples

- Configuring PowerStack Parameters: Example

- Configuring PowerStack Switch Power Parameters: Example

- Configuring PoE Port Priority: Example

Immediate Load Shedding: Examples

For power stacks in power-sharing mode, if a large power supply in the power stack fails, the stack immediately starts shutting down powered devices until the power budget matches the input power. This example has a power stack of four switches (Powerstack1) in power sharing mode and shows which devices would be shut down in the immediate load shedding process caused by loss of either of two power supplies.

The output of the show env all command shows that power supplies included in power sharing are a 715 W power supply in switch 1, and one 350 W and one 1100 W power supply in switch 4. Other power supplies are inactive (disabled or not present).

Switch# show env all
Switch 1 FAN 1 is OK
Switch 1 FAN 2 is OK
Switch 1 FAN 3 is OK
FAN PS-1 is OK
FAN PS-2 is OK
Switch 1: SYSTEM TEMPERATURE is OK
SW  PID                 Serial#     Status           Sys Pwr  PoE Pwr  Watts
--  ------------------  ----------  ---------------  -------  -------  -----
1A  PWR-C1-715WAC       LIT133705FH  OK              Good     Good     715
1B  PWR-C1-715WAC       DTN1341K018  Disabled        Good     Good     715
2A  Not Present
2B  PWR-C1-350WAC       LIT13330FNM  Disabled        Good     Good     350
3A  PWR-C1-350WAC       LIT13330FN3  Disabled        Good     Good     350
3B  Not Present
4A  PWR-C1-350WAC       DTN1342L00T  OK              Good     Good     350
4B  PWR-C1-1100WAC      LIT13370577  OK              Good     Good     1100

The output of the show stack-power privileged EXEC command shows the priorities of the powered devices and switches in the power stack.

Switch# show stack-power
Power stack name: Powerstack1
Stack mode: Power sharing
Switch 1:
Power budget: 206
Low port priority value: 17
High port priority value: 16
Switch priority value: 2
Port A status: Not shut
Port B status: Not shut
Neighbor on port A: 0022.bdcf.ab00
Neighbor on port B: 0022.bdd0.4380

Switch 2:
Power budget: 206
Low port priority value: 12
High port priority value: 11
Switch priority value: 1
Port A status: Not shut
Port B status: Not shut
Neighbor on port A: 0022.bdd0.6d00
Neighbor on port B: 0022.bdcf.af80

Switch 3:
Power budget: 656
Low port priority value: 22
High port priority value: 21
Switch priority value: 3
Port A status: Not shut
Port B status: Not shut
Neighbor on port A: 0022.bdcf.af80
Neighbor on port B: 0022.bdd0.6d00

Switch 4:
Power budget: 682
Low port priority value: 27
High port priority value: 26
Switch priority value: 4
Port A status: Not shut
Port B status: Not shut
Neighbor on port A: 0022.bdd0.4380
Neighbor on port B: 0022.bdcf.ab00

If the 715 W or 1100 W power supply fails, devices (powered devices connected to PoE ports and the switches themselves) would be shut down in the this order until power consumption drops below 105% of the rated power of the remaining power supplies:

- Devices connected to Switch 4 low priority ports (priority 27)

- Devices connected to Switch 4 high priority ports (priority 26)

- Devices connected to Switch 3 low priority ports (priority 22)

- Devices connected to Switch 3 high priority ports (priority 21)

- Devices connected to Switch 1 low priority ports (priority 17)

- Devices connected to Switch 1 high priority ports (priority 16)

- Devices connected to Switch 2 low priority ports (priority 12)

- Devices connected to Switch 2 high priority ports (priority 11)

- Switch 4 (priority 4)

- Switch 3 (priority 3)

- Switch 1 (priority 2)

Switch 2 would never have to be shut down because all power would have been lost by the time priority 1 devices were reached.

Configuring PowerStack Parameters: Example

This is an example of setting the stack power mode for the stack named power1 to redundant power mode. The largest power supply in the stack is removed from the power budget and used as a backup in case of power supply failure.

Switch(config)# stack-power stack power1
Switch(config-stackpower)# mode redundant
Switch(config-stackpower)# exit

Configuring PowerStack Switch Power Parameters: Example

This is an example of setting the switch stack power parameters for switch 3 in the stack that is connected to the power stack with the stack ID power2. If load-shedding becomes necessary, switches and powered devices in the power stack with the higher numbers are shut down first, with shutdown proceeding in order.

Switch(config)# stack-power switch 3
Switch(config-switch-stackpower)# stack power2
Switch(config-switch-stackpower)# power-priority switch 5
Switch(config-switch-stackpower)# power-priority high 12
Switch(config-switch-stackpower)# power-priority low 20
Switch(config-switch-stackpower)# exit
Switch(config-stackpower)# exit

Note

Entering the write erase and reload privileged EXEC commands do not change the power priority or power mode non-default configuration saved in the switch flash memory.

Configuring PoE Port Priority: Example

This is an example of setting the power priority of a port to high so that it is one of the last ports to shut down in case of a power failure.

Switch(config)# interface gigabitetherent1/0/1
Switch(config-if)# power inline port priority high
Switch(config-if)# exit

Where to Go Next

See the hardware installation guide for information

- Designing and connecting the power stack.

- StackPower star and ring configuration

Additional References for StackPower

Error Message Decoder

Description

Link

To help you research and resolve system error messages in this release, use the Error Message Decoder tool.

Click Here

MIBs

MIB

MIBs Link

All supported MIBs for this release.

To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

Click Here

Technical Assistance

Description

Link

The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

Click Here

Feature History and Information for StackPower

Feature Information for StackPower

Release

Modification

Cisco IOS XE 3.2SE

This feature was introduced.

Chapter 10. Configuring PoE

- Finding Feature Information

- Information about PoE

- How to Configure PoE

- Monitoring Power Status

- Additional References

- Feature Information for PoE

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to Click Here . An account on Cisco.com is not required.

Information about PoE

- Power over Ethernet Ports

- Cisco Universal Power Over Ethernet

Power over Ethernet Ports

A PoE-capable switch port automatically supplies power to one of these connected devices if the switch senses that there is no power on the circuit:

- a Cisco pre-standard powered device (such as a Cisco IP Phone or a Cisco Aironet Access Point)

- an IEEE 802.3af-compliant powered device

A powered device can receive redundant power when it is connected to a PoE switch port and to an AC power source. The device does not receive redundant power when it is only connected to the PoE port.

- Supported Protocols and Standards

- Powered-Device Detection and Initial Power Allocation

- Power Management Modes

Supported Protocols and Standards

The switch uses these protocols and standards to support PoE:

- CDP with power consumption—The powered device notifies the switch of the amount of power it is consuming. The switch does not reply to the power-consumption messages. The switch can only supply power to or remove power from the PoE port.

- Cisco intelligent power management—The powered device and the switch negotiate through power-negotiation CDP messages for an agreed-upon power-consumption level. The negotiation allows a high-power Cisco powered device, which consumes more than 7 W, to operate at its highest power mode. The powered device first boots up in low-power mode, consumes less than 7 W, and negotiates to obtain enough power to operate in high-power mode. The device changes to high-power mode only when it receives confirmation from the switch.

High-power devices can operate in low-power mode on switches that do not support power-negotiation CDP.

Cisco intelligent power management is backward-compatible with CDP with power consumption; the switch responds according to the CDP message that it receives. CDP is not supported on third-party powered devices; therefore, the switch uses the IEEE classification to determine the power usage of the device.

- IEEE 802.3af—The major features of this standard are powered-device discovery, power administration, disconnect detection, and optional powered-device power classification. For more information, see the standard.

- The Cisco UPOE feature provides the capability to source up to 60 W of power (2 x 30 W) over both signal and spare pairs of the RJ-45 Ethernet cable by using the Layer-2 power negotiation protocols such as CDP or LLDP. An LLDP and CDP request of 30 W and higher in presence of the 4-wire Cisco Proprietary spare-pair power TLV can provide power on the spare pair.

Powered-Device Detection and Initial Power Allocation

The switch detects a Cisco pre-standard or an IEEE-compliant powered device when the PoE-capable port is in the no-shutdown state, PoE is enabled (the default), and the connected device is not being powered by an AC adaptor.

After device detection, the switch determines the device power requirements based on its type:

- The initial power allocation is the maximum amount of power that a powered device requires. The switch initially allocates this amount of power when it detects and powers the powered device. As the switch receives CDP messages from the powered device and as the powered device negotiates power levels with the switch through CDP power-negotiation messages, the initial power allocation might be adjusted.

- The switch classifies the detected IEEE device within a power consumption class. Based on the available power in the power budget, the switch determines if a port can be powered. Table 1 lists these levels.

IEEE Power Classifications

Class

Maximum Power Level Required from the Switch

0 (class status unknown)

15.4 W

1

4 W

2

7 W

3

15.4 W

4

30 W (For IEEE 802.3at Type 2 powered devices)

The switch monitors and tracks requests for power and grants power only when it is available. The switch tracks its power budget (the amount of power available on the switch for PoE). Theswitch performs power-accounting calculations when a port is granted or denied power to keep the power budget up to date.

After power is applied to the port, the switch uses CDP to determine the CDP-specific power consumption requirement of the connected Cisco powered devices, which is the amount of power to allocate based on the CDP messages. The switch adjusts the power budget accordingly. This does not apply to third-party PoE devices. The switch processes a request and either grants or denies power. If the request is granted, the switch updates the power budget. If the request is denied, the switch ensures that power to the port is turned off, generates a syslog message, and updates the LEDs. Powered devices can also negotiate with the switch for more power.

With PoE+, powered devices use IEEE 802.3at and LLDP power with media dependent interface (MDI) type, length, and value descriptions (TLVs), Power-via-MDI TLVs, for negotiating power up to 30 W. Cisco pre-standard devices and Cisco IEEE powered devices can use CDP or the IEEE 802.3at power-via-MDI power negotiation mechanism to request power levels up to 30 W.

Note

The initial allocation for Class 0, Class 3, and Class 4 powered devices is 15.4 W. When a device starts up and uses CDP or LLDP to send a request for more than 15.4 W, it can be allocated up to the maximum of 30 W.

Note

The CDP-specific power consumption requirement is referred to as the actual power consumption requirement in the software configuration guides and command references.

If the switch detects a fault caused by an undervoltage, overvoltage, overtemperature, oscillator-fault, or short-circuit condition, it turns off power to the port, generates a syslog message, and updates the power budget and LEDs.

The PoE feature operates the same whether or not the switch is a stack member. The power budget is per switch and independent of any other switch in the stack. Election of a new active switch does not affect PoE operation. The active switch keeps track of the PoE status for all switches and ports in the stack and includes the status in output displays.

The stacking-capable switch also supports StackPower, which allows the power supplies to share the load across multiple systems in a stack when you connect the switches with power stack cables. You can manage the power supplies of up to four stack members as a one large power supply.

Power Management Modes

The switch supports these PoE modes:

- auto—The switch automatically detects if the connected device requires power. If the switch discovers a powered device connected to the port and if the switch has enough power, it grants power, updates the power budget, turns on power to the port on a first-come, first-served basis, and updates the LEDs. For LED information, see the hardware installation guide.

If the switch has enough power for all the powered devices, they all come up. If enough power is available for all powered devices connected to the switch, power is turned on to all devices. If there is not enough available PoE, or if a device is disconnected and reconnected while other devices are waiting for power, it cannot be determined which devices are granted or are denied power.

If granting power would exceed the system power budget, the switch denies power, ensures that power to the port is turned off, generates a syslog message, and updates the LEDs. After power has been denied, the switch periodically rechecks the power budget and continues to attempt to grant the request for power.

If a device being powered by the switch is then connected to wall power, the switch might continue to power the device. The switch might continue to report that it is still powering the device whether the device is being powered by the switch or receiving power from an AC power source.

If a powered device is removed, the switch automatically detects the disconnect and removes power from the port. You can connect a nonpowered device without damaging it.

You can specify the maximum wattage that is allowed on the port. If the IEEE class maximum wattage of the powered device is greater than the configured maximum value, the switch does not provide power to the port. If the switch powers a powered device, but the powered device later requests through CDP messages more than the configured maximum value, the switch removes power to the port. The power that was allocated to the powered device is reclaimed into the global power budget. If you do not specify a wattage, the switch delivers the maximum value. Use the auto setting on any PoE port. The auto mode is the default setting.

- static—The switch pre-allocates power to the port (even when no powered device is connected) and guarantees that power will be available for the port. The switch allocates the port configured maximum wattage, and the amount is never adjusted through the IEEE class or by CDP messages from the powered device. Because power is pre-allocated, any powered device that uses less than or equal to the maximum wattage is guaranteed to be powered when it is connected to the static port. The port no longer participates in the first-come, first-served model.

However, if the powered-device IEEE class is greater than the maximum wattage, the switch does not supply power to it. If the switch learns through CDP messages that the powered device is consuming more than the maximum wattage, the switch shuts down the powered device.

If you do not specify a wattage, the switch pre-allocates the maximum value. The switch powers the port only if it discovers a powered device. Use the static setting on a high-priority interface.

- never—The switch disables powered-device detection and never powers the PoE port even if an unpowered device is connected. Use this mode only when you want to make sure that power is never applied to a PoE-capable port, making the port a data-only port.

For most situations, the default configuration (auto mode) works well, providing plug-and-play operation. No further configuration is required. However, perform this task to configure a PoE port for a higher priority, to make it data only, or to specify a maximum wattage to disallow high-power powered devices on a port.

Stacking-capable switches also support StackPower, which allows switch power supplies to share the load across multiple systems in a stack by connecting up to four switches with power stack cables.

- Power Monitoring and Power Policing

- Power Consumption Values

Power Monitoring and Power Policing

When policing of the real-time power consumption is enabled, the switch takes action when a powered device consumes more power than the maximum amount allocated, also referred to as the cutoff-power value.

When PoE is enabled, the switch senses the real-time power consumption of the powered device. The switch monitors the real-time power consumption of the connected powered device; this is called power monitoring or power sensing. The switch also polices the power usage with the power policing feature.

Power monitoring is backward-compatible with Cisco intelligent power management and CDP-based power consumption. It works with these features to ensure that the PoE port can supply power to the powered device.

The switch senses the real-time power consumption of the connected device as follows:

1. The switch monitors the real-time power consumption on individual ports.

2. The switch records the power consumption, including peak power usage. The switch reports the information through the CISCO-POWER-ETHERNET-EXT-MIB.

3. If power policing is enabled, the switch polices power usage by comparing the real-time power consumption to the maximum power allocated to the device. The maximum power consumption is also referred to as the cutoff power on a PoE port.

If the device uses more than the maximum power allocation on the port, the switch can either turn off power to the port, or the switch can generate a syslog message and update the LEDs (the port LED is now blinking amber) while still providing power to the device based on the switch configuration. By default, power-usage policing is disabled on all PoE ports.

If error recovery from the PoE error-disabled state is enabled, the switch automatically takes the PoE port out of the error-disabled state after the specified amount of time.

If error recovery is disabled, you can manually re-enable the PoE port by using the shutdown and no shutdown interface configuration commands.

4. If policing is disabled, no action occurs when the powered device consumes more than the maximum power allocation on the PoE port, which could adversely affect the switch.

Power Consumption Values

You can configure the initial power allocation and the maximum power allocation on a port. However, these values are only the configured values that determine when the switch should turn on or turn off power on the PoE port. The maximum power allocation is not the same as the actual power consumption of the powered device. The actual cutoff power value that the switch uses for power policing is not equal to the configured power value.

When power policing is enabled, the switch polices the power usage at the switch port, which is greater than the power consumption of the device. When you are manually set the maximum power allocation, you must consider the power loss over the cable from the switch port to the powered device. The cutoff power is the sum of the rated power consumption of the powered device and the worst-case power loss over the cable.

We recommend that you enable power policing when PoE is enabled on your switch. For example, if policing is disabled and you set the cutoff-power value by using the power inline auto max 6300 interface configuration command, the configured maximum power allocation on the PoE port is 6.3 W (6300 mW). The switch provides power to the connected devices on the port if the device needs up to 6.3 W. If the CDP-power negotiated value or the IEEE classification value exceeds the configured cutoff value, the switch does not provide power to the connected device. After the switch turns on power on the PoE port, the switch does not police the real-time power consumption of the device, and the device can consume more power than the maximum allocated amount, which could adversely affect the switch and the devices connected to the other PoE ports.

Because a standalone switch supports internal power supplies, the total amount of power available for the powered devices varies depending on the power supply configuration.

- If a power supply is removed and replaced by a new power supply with less power and the switch does not have enough power for the powered devices, the switch denies power to the PoE ports in auto mode in descending order of the port numbers. If the switch still does not have enough power, the switch then denies power to the PoE ports in static mode in descending order of the port numbers.

- If the new power supply supports more power than the previous one and the switch now has more power available, the switch grants power to the PoE ports in static mode in ascending order of the port numbers. If it still has power available, the switch then grants power to the PoE ports in auto mode in ascending order of the port numbers.

The stacking-capable switch also supports StackPower, which allows power supplies to share the load across multiple systems in a stack by connecting the switches with power stack cables. You can collectively manage the power supplies of up to four stack members as a one large power supply.

Cisco Universal Power Over Ethernet

Cisco Universal Power Over Ethernet (Cisco UPOE) is a Cisco proprietary technology that extends the IEEE 802.at PoE standard to provide the capability to source up to 60 W of power over standard Ethernet cabling infrastructure (Class D or better) by using the spare pair of an RJ-45 cable (wires 4,5,7,8) with the signal pair (wires 1,2,3,6). Power on the spare pair is enabled when the switch port and end device mutually identify themselves as Cisco UPOE-capable using CDP or LLDP and the end device requests for power to be enabled on the spare pair. When the spare pair is powered, the end device can negotiate up to 60 W of power from the switch using CDP or LLDP.

If the end device is PoE-capable on both signal and spare pairs but does not support the CDP or LLDP extensions required for Cisco UPOE, a 4-pair forced mode configuration automatically enables power on both signal and spare pairs from the switch port.

How to Configure PoE

- Configuring a Power Management Mode on a PoE Port

- Enabling Power on Signal/Spare Pairs

- Configuring Power Policing

Configuring a Power Management Mode on a PoE Port

Note

When you make PoE configuration changes, the port being configured drops power. Depending on the new configuration, the state of the other PoE ports, and the state of the power budget, the port might not be powered up again. For example, port 1 is in the auto and on state, and you configure it for static mode. The switch removes power from port 1, detects the powered device, and repowers the port. If port 1 is in the auto and on state and you configure it with a maximum wattage of 10 W, the switch removes power from the port and then redetects the powered device. The switch repowers the port only if the powered device is a class 1, class 2, or a Cisco-only powered device.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    interface interface-id

4.    power inline {auto [max max-wattage] | never | static [max max-wattage]}

5.    end

6.    show power inline [interface-id | module switch-number]

7.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

interface interface-id

Example:

Switch(config)# interface gigabitethernet2/0/1

Specifies the physical port to be configured, and enters interface configuration mode.

Step 4

power inline {auto [max max-wattage] | never | static [max max-wattage]}

Example:

Switch(config-if)# power inline auto

Configures the PoE mode on the port. The keywords have these meanings:

- auto—Enables powered-device detection. If enough power is available, automatically allocates power to the PoE port after device detection. This is the default setting.

- max max-wattage—Limits the power allowed on the port. If no value is specified, the maximum is allowed.

- max max-wattage—Limits the power allowed on the port. The range for Cisco UPOE ports is 4000 to 60000 mW. If no value is specified, the maximum is allowed.

- never —Disables device detection, and disable power to the port.

Note:
If a port has a Cisco powered device connected to it, do not use the power inline never command to configure the port. A false link-up can occur, placing the port into the error-disabled state.

- static—Enables powered-device detection. Pre-allocate (reserve) power for a port before the switch discovers the powered device. The switch reserves power for this port even when no device is connected and guarantees that power will be provided upon device detection.

The switch allocates power to a port configured in static mode before it allocates power to a port configured in auto mode.

Step 5

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Step 6

show power inline [interface-id | module switch-number]

Example:

Switch# show power inline

Displays PoE status for a switch or a switch stack, for the specified interface, or for a specified stack member.

The module switch-number keywords are supported only on stacking-capable switches.

Step 7

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Enabling Power on Signal/Spare Pairs

Note

Do not enter this command if the end device cannot source inline power on the spare pair or if the end device supports the CDP or LLDP extensions for Cisco UPOE.

SUMMARY STEPS

1.    configure terminal

2.    interface interface-id

3.    power inline four-pair forced

4.    end

DETAILED STEPS

Command or Action

Purpose

Step 1

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 2

interface interface-id

Example:

Switch(config)# interface gigabitethernet2/0/1

Specifies the physical port to be configured, and enters interface configuration mode.

Step 3

power inline four-pair forced

Example:

Switch(config-if)# power inline four-pair forced

Enables power on both signal and spare pairs from a switch port.

Step 4

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Configuring Power Policing

By default, the switch monitors the real-time power consumption of connected powered devices. You can configure the switch to police the power usage. By default, policing is disabled.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    interface interface-id

4.    power inline police [action{log | errdisable}]

5.    exit

6.    Use one of the following:

- errdisable detect cause inline-power

- errdisable recovery cause inline-power

- errdisable recovery interval interval

7.    exit

8.    Use one of the following:

- show power inline police

- show errdisable recovery

9.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

enable

Example:

Switch> enable

Enables privileged EXEC mode. Enter your password if prompted.

Step 2

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 3

interface interface-id

Example:

Switch(config)# interface gigabitethernet2/0/1

Specifies the physical port to be configured, and enter interface configuration mode.

Step 4

power inline police [action{log | errdisable}]

Example:

Switch(config-if)# power inline police

If the real-time power consumption exceeds the maximum power allocation on the port, configures the switch to take one of these actions:

- power inline police—Shuts down the PoE port, turns off power to it, and puts it in the error-disabled state.

Note:
You can enable error detection for the PoE error-disabled cause by using the errdisable detect cause inline-power global configuration command. You can also enable the timer to recover from the PoE error-disabled state by using the errdisable recovery cause inline-power interval interval global configuration command.

- power inline police action errdisable—Turns off power to the port if the real-time power consumption exceeds the maximum power allocation on the port.

- power inline police action log—Generates a syslog message while still providing power to the port.

If you do not enter the action log keywords, the default action shuts down the port and puts the port in the error-disabled state.

Step 5

exit

Example:

Switch(config-if)# exit

Returns to global configuration mode.

Step 6

Use one of the following:

- errdisable detect cause inline-power

- errdisable recovery cause inline-power

- errdisable recovery interval interval

Example:

Switch(config)# errdisable detect cause inline-power

Switch(config)# errdisable recovery cause inline-power

Switch(config)# errdisable recovery interval 100

(Optional) Enables error recovery from the PoE error-disabled state, and configures the PoE recover mechanism variables.

By default, the recovery interval is 300 seconds.

For interval interval, specifies the time in seconds to recover from the error-disabled state. The range is 30 to 86400.

Step 7

exit

Example:

Switch(config)# exit

Returns to privileged EXEC mode.

Step 8

Use one of the following:

- show power inline police

- show errdisable recovery

Example:

Switch# show power inline police

Switch# show errdisable recovery

Displays the power monitoring status, and verify the error recovery settings.

Step 9

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Monitoring Power Status

Show Commands for Power Status

Command

Purpose

show env power switch [switch-number]

(Optional) Displays the status of the internal power supplies for each switch in the stack or for the specified switch.

The range is 1 to 9, depending on the switch member numbers in the stack. These keywords are available only on stacking-capable switches.

show power inline [interface-id | module switch-number]

Displays PoE status for a switch or switch stack, for an interface, or for a specific switch in the stack.

show power inline police

Displays the power policing data.

Additional References

Error Message Decoder

Description

Link

To help you research and resolve system error messages in this release, use the Error Message Decoder tool.

Click Here

MIBs

MIB

MIBs Link

All supported MIBs for this release.

To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

Click Here

Technical Assistance

Description

Link

The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

Click Here

Feature Information for PoE

Release

Modification

Cisco IOS XE 3.2SE

This feature was introduced.

Cisco IOS XE 3.3SE

The four-pair forced keywords were added.

Chapter 11. Configuring EEE

- Finding Feature Information

- Information About EEE

- Restrictions for EEE

- How to Configure EEE

- Monitoring EEE

- Configuration Examples for Configuring EEE

- Additional References

- Feature History and Information for Configuring EEE

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to Click Here . An account on Cisco.com is not required.

Information About EEE

- EEE Overview

- Default EEE Configuration

EEE Overview

Energy Efficient Ethernet (EEE) is an IEEE 802.3az standard that is designed to reduce power consumption in Ethernet networks during idle periods.

EEE can be enabled on devices that support low power idle (LPI) mode. Such devices can save power by entering LPI mode during periods of low utilization. In LPI mode, systems on both ends of the link can save power by shutting down certain services. EEE provides the protocol needed to transition into and out of LPI mode in a way that is transparent to upper layer protocols and applications.

Default EEE Configuration

EEE is disabled by default.

Restrictions for EEE

EEE has the following restrictions:

- Changing the EEE configuration resets the interface because the device has to restart Layer 1 autonegotiation.

- You might want to enable the Link Layer Discovery Protocol (LLDP) for devices that require longer wakeup times before they are able to accept data on their receive paths. Doing so enables the device to negotiate for extended system wakeup times from the transmitting link partner.

How to Configure EEE

You can enable or disable EEE on an interface that is connected to an EEE-capable link partner.

- Enabling or Disabling EEE

Enabling or Disabling EEE

SUMMARY STEPS

1.    configure terminal

2.    interface interface-id

3.    power efficient-ethernet auto

4.    no power efficient-ethernet auto

5.    end

6.    copy running-config startup-config

DETAILED STEPS

Command or Action

Purpose

Step 1

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 2

interface interface-id

Example:

Switch(config)# interface gigabitethernet1/0/1

Specifies the interface to be configured, and enter interface configuration mode.

Step 3

power efficient-ethernet auto

Example:

Switch(config-if)# power efficient-ethernet auto

Enables EEE on the specified interface. When EEE is enabled, the device advertises and autonegotiates EEE to its link partner.

Step 4

no power efficient-ethernet auto

Example:

Switch(config-if)# no power efficient-ethernet auto

Disables EEE on the specified interface.

Step 5

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Step 6

copy running-config startup-config

Example:

Switch# copy running-config startup-config

(Optional) Saves your entries in the configuration file.

Monitoring EEE

Commands for Displaying EEE Settings

Command

Purpose

show eee capabilities interface interface-id

Displays EEE capabilities for the specified interface.

show eee status interface interface-id

Displays EEE status information for the specified interface.

Configuration Examples for Configuring EEE

This example shows how to enable EEE for an interface:

Switch# configure terminal
Switch(config)# interface gigabitethernet1/0/1
Switch(config-if)# power efficient-ethernet auto

This example shows how to disable EEE for an interface:

Switch# configure terminal
Switch(config)# interface gigabitethernet1/0/1
Switch(config-if)# no power efficient-ethernet auto

Additional References

Error Message Decoder

Description

Link

To help you research and resolve system error messages in this release, use the Error Message Decoder tool.

Click Here

MIBs

MIB

MIBs Link

All supported MIBs for this release.

To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

Click Here

Technical Assistance

Description

Link

The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

Click Here

Feature History and Information for Configuring EEE

Release

Modification

Cisco IOS XE 3.2SE

This feature was introduced.

Preface

- Document Conventions

- Related Documentation

- Obtaining Documentation and Submitting a Service Request

Document Conventions

This document uses the following conventions:

Convention

Description

^ or Ctrl

Both the ^ symbol and Ctrl represent the Control (Ctrl) key on a keyboard. For example, the key combination ^D or Ctrl-D means that you hold down the Control key while you press the D key. (Keys are indicated in capital letters but are not case sensitive.)

bold font

Commands and keywords and user-entered text appear in bold font.

Italic font

Document titles, new or emphasized terms, and arguments for which you supply values are in italic font.

Courier font

Terminal sessions and information the system displays appear in courier font.

Bold Courier font

Bold Courier font indicates text that the user must enter.

[x]

Elements in square brackets are optional.

...

An ellipsis (three consecutive nonbolded periods without spaces) after a syntax element indicates that the element can be repeated.

|

A vertical line, called a pipe, indicates a choice within a set of keywords or arguments.

[x | y]

Optional alternative keywords are grouped in brackets and separated by vertical bars.

{x | y}

Required alternative keywords are grouped in braces and separated by vertical bars.

[x {y | z}]

Nested set of square brackets or braces indicate optional or required choices within optional or required elements. Braces and a vertical bar within square brackets indicate a required choice within an optional element.

string

A nonquoted set of characters. Do not use quotation marks around the string or the string will include the quotation marks.

< >

Nonprinting characters such as passwords are in angle brackets.

[ ]

Default responses to system prompts are in square brackets.

!, #

An exclamation point (!) or a pound sign (#) at the beginning of a line of code indicates a comment line.

Reader Alert Conventions

This document may use the following conventions for reader alerts:

Note

Means reader take note. Notes contain helpful suggestions or references to material not covered in the manual.

Tip

Means the following information will help you solve a problem.

Caution

Means reader be careful. In this situation, you might do something that could result in equipment damage or loss of data.

Timesaver

Means the described action saves time. You can save time by performing the action described in the paragraph.

Warning

IMPORTANT SAFETY INSTRUCTIONS

This warning symbol means danger. You are in a situation that could cause bodily injury. Before you work on any equipment, be aware of the hazards involved with electrical circuitry and be familiar with standard practices for preventing accidents. Use the statement number provided at the end of each warning to locate its translation in the translated safety warnings that accompanied this device. Statement 1071

SAVE THESE INSTRUCTIONS

Related Documentation

Note

Before installing or upgrading the switch, refer to the switch release notes.

- Cisco Catalyst 3850 Switch documentation, located at:

Click Here

- Cisco SFP and SFP+ modules documentation, including compatibility matrixes, located at:

Click Here

- Cisco Validated Designs documents, located at:

Click Here

- Error Message Decoder, located at:

Click Here

Obtaining Documentation and Submitting a Service Request

For information on obtaining documentation, submitting a service request, and gathering additional information, see the monthly What's New in Cisco Product Documentation, which also lists all new and revised Cisco technical documentation, at:

Click Here

Subscribe to the What's New in Cisco Product Documentation as a Really Simple Syndication (RSS) feed and set content to be delivered directly to your desktop using a reader application. The RSS feeds are a free service and Cisco currently supports RSS version 2.0.

THE SPECIFICATIONS AND INFORMATION REGARDING THE PRODUCTS IN THIS MANUAL ARE SUBJECT TO CHANGE WITHOUT NOTICE. ALL STATEMENTS, INFORMATION, AND RECOMMENDATIONS IN THIS MANUAL ARE BELIEVED TO BE ACCURATE BUT ARE PRESENTED WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED. USERS MUST TAKE FULL RESPONSIBILITY FOR THEIR APPLICATION OF ANY PRODUCTS.

THE SOFTWARE LICENSE AND LIMITED WARRANTY FOR THE ACCOMPANYING PRODUCT ARE SET FORTH IN THE INFORMATION PACKET THAT SHIPPED WITH THE PRODUCT AND ARE INCORPORATED HEREIN BY THIS REFERENCE. IF YOU ARE UNABLE TO LOCATE THE SOFTWARE LICENSE OR LIMITED WARRANTY, CONTACT YOUR CISCO REPRESENTATIVE FOR A COPY.

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NOTWITHSTANDING ANY OTHER WARRANTY HEREIN, ALL DOCUMENT FILES AND SOFTWARE OF THESE SUPPLIERS ARE PROVIDED “AS IS" WITH ALL FAULTS. CISCO AND THE ABOVE-NAMED SUPPLIERS DISCLAIM ALL WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, THOSE OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OR ARISING FROM A COURSE OF DEALING, USAGE, OR TRADE PRACTICE.

IN NO EVENT SHALL CISCO OR ITS SUPPLIERS BE LIABLE FOR ANY INDIRECT, SPECIAL, CONSEQUENTIAL, OR INCIDENTAL DAMAGES, INCLUDING, WITHOUT LIMITATION, LOST PROFITS OR LOSS OR DAMAGE TO DATA ARISING OUT OF THE USE OR INABILITY TO USE THIS MANUAL, EVEN IF CISCO OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental.

Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S. and other countries. To view a list of Cisco trademarks, go to this URL: Click Here . Third-party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (1110R)

Supported Protocols and Standards

The switch uses these protocols and standards to support PoE:

- CDP with power consumption—The powered device notifies the switch of the amount of power it is consuming. The switch does not reply to the power-consumption messages. The switch can only supply power to or remove power from the PoE port.

- Cisco intelligent power management—The powered device and the switch negotiate through power-negotiation CDP messages for an agreed-upon power-consumption level. The negotiation allows a high-power Cisco powered device, which consumes more than 7 W, to operate at its highest power mode. The powered device first boots up in low-power mode, consumes less than 7 W, and negotiates to obtain enough power to operate in high-power mode. The device changes to high-power mode only when it receives confirmation from the switch.

High-power devices can operate in low-power mode on switches that do not support power-negotiation CDP.

Cisco intelligent power management is backward-compatible with CDP with power consumption; the switch responds according to the CDP message that it receives. CDP is not supported on third-party powered devices; therefore, the switch uses the IEEE classification to determine the power usage of the device.

- IEEE 802.3af—The major features of this standard are powered-device discovery, power administration, disconnect detection, and optional powered-device power classification. For more information, see the standard.

- The Cisco UPOE feature provides the capability to source up to 60 W of power (2 x 30 W) over both signal and spare pairs of the RJ-45 Ethernet cable by using the Layer-2 power negotiation protocols such as CDP or LLDP. An LLDP and CDP request of 30 W and higher in presence of the 4-wire Cisco Proprietary spare-pair power TLV can provide power on the spare pair.

Related Information

Cisco Universal Power Over Ethernet

StackPower Modes

You can configure the power stack to run in one of two modes:

- In power-sharing mode (the default), all input power is available to be used for power loads. The total available power in all switches in the power stack (up to four) is treated as a single large power supply, with power available to all switches and to all powered devices connected to PoE ports. In this mode, the total available power is used for power budgeting decisions and no power is reserved to accommodate power-supply failures. If a power supply fails, powered devices and switches could be shut down (load shedding).

- In redundant mode, the power from the largest power supply in the system is subtracted from the power budget, which reduces the total available power, but provides backup power in case of a power-supply failure. Although there is less available power in the pool for switches and powered devices to draw from, the possibility of having to shut down switches or powered devices in case of a power failure or extreme power load is reduced.

In addition, you can configure the mode to run a strict power budget or a non-strict (relaxed) power budget. In both modes, power is denied when there is no more power available in the power budget.

- In strict mode, when a power supply fails and the available power drops below the budgeted power, the system balances the budget through load shedding of powered devices, even if the actual power being consumed is less than the available power.

- In non-strict mode, the power stack is allowed to run in an over-allocated state and is stable as long as the actual power does not exceed the available power. In this mode, a powered device drawing more than normal power could cause the power stack to start shedding loads. This is normally not a problem because most devices do not run at full power and the chances of multiple powered devices in the stack requiring maximum power at the same time is small.

You configure power modes at a power-stack level (that is, the mode is the same for all switches in the power stack).

You can also configure a switch connected in a power stack to not participate in the power stack by setting the switch to standalone power mode. This mode shuts down both stack power ports.

Related Tasks

Configuring PowerStack Parameters

Related References

Configuring PowerStack Parameters: Example

Configuring PowerStack Parameters

SUMMARY STEPS

1.    configure terminal

2.    stack-power stack power stack name

3.    mode {power-sharing | redundant} [strict]

4.    end

5.    show stack-power

DETAILED STEPS

Command or Action

Purpose

Step 1

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 2

stack-power stack power stack name

Example:

Switch(config)# stack-power stack power 1

Enters the stack power stack name and enter power stack configuration mode. The name can be up to 31 characters.

Step 3

mode {power-sharing | redundant} [strict]

Example:

Switch(config-stackpower)# mode redundant

Sets the operating mode for the power stack:

- power-sharing—The input power from all switches in the power stack can be used for loads, and the total available power appears as one huge power supply. This is the default.

- redundant—The largest power supply is removed from the power pool to be used as backup power in case one of the other power supplies fails. This is the recommended mode if enough power is available in the system.

- strict—(Optional) Configures the power stack mode to run a strict power budget. The stack power needs cannot exceed the available power. The default is non-strict.

Step 4

end

Example:

Switch(config-stackpower)# end

Returns to privileged EXEC mode.

Step 5

show stack-power

Example:

Switch# show stack-power

Verifies your entries.

Related Concepts

StackPower Modes

Related References

Configuring PowerStack Parameters: Example

Configuring PowerStack Parameters: Example

This is an example of setting the stack power mode for the stack named power1 to redundant power mode. The largest power supply in the stack is removed from the power budget and used as a backup in case of power supply failure.

Switch(config)# stack-power stack power1
Switch(config-stackpower)# mode redundant
Switch(config-stackpower)# exit

Related Concepts

StackPower Modes

Related Tasks

Configuring PowerStack Parameters

Power Priority

You can configure the priority of a switch or powered device to receive power. This priority determines the order in which devices are shut down in case of a power shortage. You can configure three priorities per system: the system (or switch) priority, the priority of the high-priority PoE ports on a switch, and the priority of the low-priority PoE ports on a switch.

You set port priority at the interface level for powered devices connected to a PoE port. By default, all ports are low priority.

You configure the priority values of each switch in the power stack and of all high and low priority ports on that switch to set the order in which switches and ports are shut down when power is lost and load shedding must occur. Priority values are from 1 to 27; switches and ports with highest values are shut down first.

Note

The 27 priorities are used to accommodate power stacks connected in a star configuration with the expandable power supply. In this configuration, there would be nine members (switches) per system with three priorities per switch.

On any switch, the switch priority must be lower than port priorities. and the high priority value must be set lower than the low priority value. We recommend that you configure different priority values for each switch and for its high priority ports and low priority ports. This limits the number of devices shut down at one time during a loss of power. If you try to configure the same priority value on different switches in a power stack, the configuration is allowed, but you receive a warning message.

The default priority ranges, if none are configured, are 1-9 for switches, 10-18 for high-priority ports, and 19-27 for low-priority ports.

Related Tasks

Configuring PowerStack Switch Power Parameters

Related References

Configuring PowerStack Switch Power Parameters: Example

Configuring PowerStack Switch Power Parameters

SUMMARY STEPS

1.    configure terminal

2.    stack-power switch switch-number

3.    stack [power-stack-name]

4.    power-priority switch value

5.    power-priority high value

6.    power-priority low value

7.    end

8.    show stack-power

DETAILED STEPS

Command or Action

Purpose

Step 1

configure terminal

Example:

Switch# configure terminal

Step 2

stack-power switch switch-number

Example:

Switch(config)# stack-power switch 4

Enters global configuration mode.

Enters switch stack power configuration mode for the stack member switch number. The range is from 1 to 9.

Note:
Only four switches can belong to the same power stack.

Step 3

stack [power-stack-name]

Example:

Switch(config-switch-stackpower)# stack power2

Enters the name of the power stack to which the switch belongs. The name can be up to 31 characters. If you do not enter a name and no other switches in the power stack have a name configured, a power-stack name is automatically generated.

Step 4

power-priority switch value

Example:

Switch(config-switch-stackpower)# power-priority switch 5

Sets the power priority of the switch. The range is from 1 to 27. This value must be lower than the value set for the low and high-priority ports.

Step 5

power-priority high value

Example:

Switch(config-switch-stackpower)# power-priority high 12

Sets the power priority of the PoE ports on the switch that are configured as high-priority ports. The range is from 1 to 27, with 1 as the highest priority. The high value must be lower than the value set for the low-priority ports and higher than the value set for the switch.

Step 6

power-priority low value

Example:

Switch(config-switch-stackpower)# power-priority low 20

Sets the power priority of the PoE ports on the switch that are configured as low-priority ports. The range is from 1 to 27. This value must be higher than the value set for the high-priority ports and the value set for the switch.

Step 7

end

Example:

Switch(config-switch-stackpower)# end

Returns to privileged EXEC mode.

Step 8

show stack-power

Example:

Switch# show stack-power

Verifies your entries.

Related Concepts

Power Priority

Related References

Configuring PowerStack Switch Power Parameters: Example

Configuring PowerStack Switch Power Parameters: Example

This is an example of setting the switch stack power parameters for switch 3 in the stack that is connected to the power stack with the stack ID power2. If load-shedding becomes necessary, switches and powered devices in the power stack with the higher numbers are shut down first, with shutdown proceeding in order.

Switch(config)# stack-power switch 3
Switch(config-switch-stackpower)# stack power2
Switch(config-switch-stackpower)# power-priority switch 5
Switch(config-switch-stackpower)# power-priority high 12
Switch(config-switch-stackpower)# power-priority low 20
Switch(config-switch-stackpower)# exit
Switch(config-stackpower)# exit

Note

Entering the write erase and reload privileged EXEC commands do not change the power priority or power mode non-default configuration saved in the switch flash memory.

Related Concepts

Power Priority

Related Tasks

Configuring PowerStack Switch Power Parameters

Power Priority

You can configure the priority of a switch or powered device to receive power. This priority determines the order in which devices are shut down in case of a power shortage. You can configure three priorities per system: the system (or switch) priority, the priority of the high-priority PoE ports on a switch, and the priority of the low-priority PoE ports on a switch.

You set port priority at the interface level for powered devices connected to a PoE port. By default, all ports are low priority.

You configure the priority values of each switch in the power stack and of all high and low priority ports on that switch to set the order in which switches and ports are shut down when power is lost and load shedding must occur. Priority values are from 1 to 27; switches and ports with highest values are shut down first.

Note

The 27 priorities are used to accommodate power stacks connected in a star configuration with the expandable power supply. In this configuration, there would be nine members (switches) per system with three priorities per switch.

On any switch, the switch priority must be lower than port priorities. and the high priority value must be set lower than the low priority value. We recommend that you configure different priority values for each switch and for its high priority ports and low priority ports. This limits the number of devices shut down at one time during a loss of power. If you try to configure the same priority value on different switches in a power stack, the configuration is allowed, but you receive a warning message.

The default priority ranges, if none are configured, are 1-9 for switches, 10-18 for high-priority ports, and 19-27 for low-priority ports.

Related Tasks

Configuring PoE Port Priority

Related References

Configuring PoE Port Priority: Example

Configuring PoE Port Priority

SUMMARY STEPS

1.    configure terminal

2.    interface interface-id

3.    power inline port priority {high | low}

4.    end

5.    show power inline priority

DETAILED STEPS

Command or Action

Purpose

Step 1

configure terminal

Example:

Switch# configure terminal

Enters global configuration mode.

Step 2

interface interface-id

Example:

Switch(config)# interface gigabitethernet 1/0/1

Enters the interface ID of the port in the stack and enters interface configuration mode. The interface must be a PoE port.

Step 3

power inline port priority {high | low}

Example:

Switch(config-if)# power inline port priority high

Sets the power priority of the port to high or low. Powered devices connected to low priority ports are shut down first in case of a power reduction. The default is low priority.

Note:
Although the power inline port priority {high | low} command is visible on the nonstacking switch PoE ports, it has no effect because these switches do not participate in stack power.

Step 4

end

Example:

Switch(config-if)# end

Returns to privileged EXEC mode.

Step 5

show power inline priority

Example:

Switch# show power inline priority

Verifies your entries.

Related Concepts

Power Priority

Related References

Configuring PoE Port Priority: Example

Configuring PoE Port Priority: Example

This is an example of setting the power priority of a port to high so that it is one of the last ports to shut down in case of a power failure.

Switch(config)# interface gigabitetherent1/0/1
Switch(config-if)# power inline port priority high
Switch(config-if)# exit

Related Concepts

Power Priority

Related Tasks

Configuring PoE Port Priority

Load Shedding

Load shedding is the process of shutting down devices in case of power supply, cable, or system failures. For power stacks in power-sharing mode, there are two types of load-shedding: immediate and graceful.

- Immediate load shed occurs when a failure could cause the power stack to fail very quickly. For example, if the largest power supply in the power stack fails, this could cause the stack to immediately start shutting down powered devices.

- Graceful load-shedding can occur when a smaller power supply fails. Switches and powered devices are shut down in order of their configured priority, starting with devices with priority 27, until the power budget matches the input power.

Graceful load shedding is always enabled and immediate load shedding occurs only when necessary, so both can occur at the same time.

Note

Load shedding does not occur in redundant mode unless two or more power supplies fail, because the largest power supply is used as a backup power source.

Notes on load shedding:

- The method (immediate or graceful) is not user-configurable, but is based on the power budget.

- Immediate load shedding also occurs in the order of configured priority, but occurs very quickly to prevent hardware damage caused by loss of power.

- If a switch is shut down because of load shedding, the output of the show stack-power privileged EXEC command still includes the MAC address of the shut down switch as a neighbor switch, even though the switch is down. This command output shows the StackPower topology, even if there is not enough power to power up a switch.

Related References

Immediate Load Shedding: Examples

Immediate Load Shedding: Examples

For power stacks in power-sharing mode, if a large power supply in the power stack fails, the stack immediately starts shutting down powered devices until the power budget matches the input power. This example has a power stack of four switches (Powerstack1) in power sharing mode and shows which devices would be shut down in the immediate load shedding process caused by loss of either of two power supplies.

The output of the show env all command shows that power supplies included in power sharing are a 715 W power supply in switch 1, and one 350 W and one 1100 W power supply in switch 4. Other power supplies are inactive (disabled or not present).

Switch# show env all
Switch 1 FAN 1 is OK
Switch 1 FAN 2 is OK
Switch 1 FAN 3 is OK
FAN PS-1 is OK
FAN PS-2 is OK
Switch 1: SYSTEM TEMPERATURE is OK
SW  PID                 Serial#     Status           Sys Pwr  PoE Pwr  Watts
--  ------------------  ----------  ---------------  -------  -------  -----
1A  PWR-C1-715WAC       LIT133705FH  OK              Good     Good     715
1B  PWR-C1-715WAC       DTN1341K018  Disabled        Good     Good     715
2A  Not Present
2B  PWR-C1-350WAC       LIT13330FNM  Disabled        Good     Good     350
3A  PWR-C1-350WAC       LIT13330FN3  Disabled        Good     Good     350
3B  Not Present
4A  PWR-C1-350WAC       DTN1342L00T  OK              Good     Good     350
4B  PWR-C1-1100WAC      LIT13370577  OK              Good     Good     1100

The output of the show stack-power privileged EXEC command shows the priorities of the powered devices and switches in the power stack.

Switch# show stack-power
Power stack name: Powerstack1
Stack mode: Power sharing
Switch 1:
Power budget: 206
Low port priority value: 17
High port priority value: 16
Switch priority value: 2
Port A status: Not shut
Port B status: Not shut
Neighbor on port A: 0022.bdcf.ab00
Neighbor on port B: 0022.bdd0.4380

Switch 2:
Power budget: 206
Low port priority value: 12
High port priority value: 11
Switch priority value: 1
Port A status: Not shut
Port B status: Not shut
Neighbor on port A: 0022.bdd0.6d00
Neighbor on port B: 0022.bdcf.af80

Switch 3:
Power budget: 656
Low port priority value: 22
High port priority value: 21
Switch priority value: 3
Port A status: Not shut
Port B status: Not shut
Neighbor on port A: 0022.bdcf.af80
Neighbor on port B: 0022.bdd0.6d00

Switch 4:
Power budget: 682
Low port priority value: 27
High port priority value: 26
Switch priority value: 4
Port A status: Not shut
Port B status: Not shut
Neighbor on port A: 0022.bdd0.4380
Neighbor on port B: 0022.bdcf.ab00

If the 715 W or 1100 W power supply fails, devices (powered devices connected to PoE ports and the switches themselves) would be shut down in the this order until power consumption drops below 105% of the rated power of the remaining power supplies:

- Devices connected to Switch 4 low priority ports (priority 27)

- Devices connected to Switch 4 high priority ports (priority 26)

- Devices connected to Switch 3 low priority ports (priority 22)

- Devices connected to Switch 3 high priority ports (priority 21)

- Devices connected to Switch 1 low priority ports (priority 17)

- Devices connected to Switch 1 high priority ports (priority 16)

- Devices connected to Switch 2 low priority ports (priority 12)

- Devices connected to Switch 2 high priority ports (priority 11)

- Switch 4 (priority 4)

- Switch 3 (priority 3)

- Switch 1 (priority 2)

Switch 2 would never have to be shut down because all power would have been lost by the time priority 1 devices were reached.

Related Concepts

Load Shedding