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Catalyst 2950 and Catalyst 2955 Switch Command Reference, 12.1(22)EA11 and Later
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Index
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Preface
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Using the Command-Line Interface
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Catalyst 2950 and 2955 Switch Cisco IOS Commands - a through r
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Catalyst 2950 and 2955 Switch Cisco IOS Commands - s
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Catalyst 2950 and 2955 Switch Cisco IOS Catalyst 2950 and 2955 Switch Cisco IOS Commands - t through z \r\n
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Catalyst 2955 Alarm Commands
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Catalyst 2950 and 2955 Switch Boot Loader Commands
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Catalyst 2950 and 2955 Switch Debug Commands
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Table Of Contents
Catalyst 2950 and 2955 Cisco IOS Commands
clear controllers ethernet-controller
clear controllers lre link monitor
clear spanning-tree detected-protocols
deny (access-list configuration)
deny (MAC access-list configuration)
ip dhcp snooping information option
ip dhcp snooping information option allow-untrusted
ip igmp snooping mrouter learn pim v2
ip igmp snooping report-suppression
ip igmp snooping source-only-learning
ip igmp snooping vlan immediate-leave
ip igmp snooping vlan last-member-query interval
mac address-table notification
permit (access-list configuration)
permit (MAC access-list configuration)
profile (interface configuration)
profile (sequence configuration)
Catalyst 2950 and 2955 Cisco IOS Commands
aaa accounting dot1x
Use the aaa accounting dot1x global configuration command to enable authentication, authorization, and accounting (AAA) accounting and to create method lists defining specific accounting methods on a per-line or per-interface basis for IEEE 802.1x sessions. Use the no form of this command to disable IEEE 802.1x accounting.
aaa accounting dot1x {name | default} start-stop {broadcast group {name | radius | tacacs+} [group {name | radius | tacacs+} ... ] | group {name | radius | tacacs+} [group {name | radius | tacacs+} ...]}
no aaa accounting dot1x {name | default}
Syntax Description
Defaults
AAA accounting is disabled.
Command Modes
Global configuration
Command History
Usage Guidelines
This command requires access to a RADIUS server.
Note
We recommend that you enter the dot1x re-authentication interface configuration command before configuring IEEE 802.1x RADIUS accounting on an interface.
Examples
This example shows how to configure IEEE 802.1x accounting:
Switch(config)# aaa new modelSwitch(config)# aaa accounting dot1x default start-stop group radius
Note
Related Commands
Specifies one or more AAA methods for use on interfaces running IEEE 802.1x.
Enables or disables periodic re-authentication.
dot1x timeout reauth-period
Sets the number of seconds between re-authentication attempts.
aaa authentication dot1x
Use the aaa authentication dot1x global configuration command to specify the authentication, authorization, and accounting (AAA) method to use on ports complying with IEEE 802.1x authentication. Use the no form of this command to disable authentication.
aaa authentication dot1x {default} method1
no aaa authentication dot1x {default}
Syntax Description
Note
Defaults
No authentication is performed.
Command Modes
Global configuration
Command History
Usage Guidelines
The method argument identifies the method that the authentication algorithm tries in the given sequence to validate the password provided by the client. The only method that is truly IEEE 802.1x-compliant is the group radius method, in which the client data is validated against a RADIUS authentication server.
If you specify group radius, you must configure the RADIUS server by entering the radius-server host global configuration command.
Use the show running-config privileged EXEC command to display the configured lists of authentication methods.
Examples
This example shows how to enable AAA and how to create an IEEE 802.1x-compliant authentication list. This authentication first tries to contact a RADIUS server. If this action returns an error, the user is not allowed access to the network.
Switch(config)# aaa new modelSwitch(config)# aaa authentication dot1x default group radiusYou can verify your settings by entering the show running-config privileged EXEC command.
Related Commands
access-list (IP extended)
Use the extended version of the access-list global configuration command to configure an extended IP access control list (ACL). Use the no form of this command to remove an extended IP ACL.
access-list access-list-number {deny | permit | remark} protocol {source source-wildcard | host source | any} [operator port] {destination destination-wildcard | host destination | any} [operator port] [dscp dscp-value] [time-range time-range-name]
no access-list access-list-number
This command is available on physical interfaces only if your switch is running the enhanced software image (EI).
Syntax Description
Defaults
The default extended ACL is always terminated by an implicit deny statement for all packets.
Command Modes
Global configuration
Command History
Usage Guidelines
Plan your access conditions carefully. The ACL is always terminated by an implicit deny statement for all packets.
You can use ACLs to control virtual terminal line access by controlling the transmission of packets on an interface.
Extended ACLs support only the TCP and UDP protocols.
Use the show ip access-lists command to display the contents of IP ACLs.
Use the show access-lists command to display the contents of all ACLs.
Note
Examples
This example shows how to configure an extended IP ACL that allows only TCP traffic to the destination IP address 128.88.1.2 with a TCP port number of 25 and how to apply it to an interface:
Switch(config)# access-list 102 permit tcp any host 128.88.1.2 eq 25Switch(config)# interface fastethernet0/8Switch(config-if)# ip access-group 102 inThis is an example of an extended ACL that allows TCP traffic only from two specified networks. The wildcard bits apply to the host portions of the network addresses. Any host with a source address that does not match the ACL statements is denied.
access-list 104 permit tcp 192.5.0.0 0.0.255.255 anyaccess-list 104 permit tcp 128.88.0.0 0.0.255.255 any
Note
You can verify your settings by entering the show ip access-lists or show access-lists privileged EXEC command.
Related Commands
Configures a standard IP ACL.
Controls access to an interface.
Displays ACLs configured on the switch.
Displays IP ACLs configured on the switch.
access-list (IP standard)
Use the standard version of the access-list global configuration command to configure a standard IP access control list (ACL). Use the no form of this command to remove a standard IP ACL.
access-list access-list-number {deny | permit | remark} {source source-wildcard | host source | any}
no access-list access-list-number
This command is available on physical interfaces only if your switch is running the enhanced software image (EI).
Syntax Description
Defaults
The default standard ACL is always terminated by an implicit deny statement for all packets.
Command Modes
Global configuration
Command History
Usage Guidelines
Plan your access conditions carefully. The ACL is always terminated by an implicit deny statement for all packets.
You can use ACLs to control virtual terminal line access by controlling the transmission of packets on an interface.
Use the show ip access-lists command to display the contents of IP ACLs.
Use the show access-lists command to display the contents of all ACLs.
Note
Examples
This example shows how to configure a standard IP ACL that allows only traffic from the host network 128.88.1.10 and how to apply it to an interface:
Switch(config)# access-list 12 permit host 128.88.1.10Switch(config)# interface gigabitethernet0/1Switch(config-if)# ip access-group 12 inThis is an example of an standard ACL that allows traffic only from three specified networks. The wildcard bits apply to the host portions of the network addresses. Any host with a source address that does not match the ACL statements is denied.
access-list 14 permit 192.5.34.0 0.0.0.255access-list 14 permit 128.88.0.0 0.0.0.255access-list 14 permit 36.1.1.0 0.0.0.255
Note
You can verify your settings by entering the show ip access-lists or show access-lists privileged EXEC command.
Related Commands
Configures an extended IP ACL.
Controls access to an interface.
Displays ACLs configured on the switch.
Displays IP ACLs configured on the switch.
archive download-sw
Use the archive download-sw privileged EXEC command to download a new image from a TFTP server to a Catalyst 2950 Long-Reach Ethernet (LRE) switch and to overwrite or to keep the existing image.
archive download-sw {/force-reload | /imageonly | /leave-old-sw | /no-set-boot | /overwrite | /reload | /safe} source-url
This command is available only on the Catalyst 2950 LRE switches.
Syntax Description
Defaults
Both the software image and device manager files are downloaded.
The new image is downloaded to the flash: file system.
The BOOT environment variable is changed to point to the new software image on the flash: file system.
Image names are case sensitive; the image file is provided in tar format.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
Use the /overwrite option to overwrite the image on the flash device with the downloaded one.
If the flash device has sufficient space to hold two images and you want to overwrite one of these images with the same version, you must specify the /overwrite option.
If you specify the command without the /overwrite option, the download algorithm verifies that the new image is not the same as the one on the switch flash device. If the images are the same, the download does not occur. If the images are different, the old image is deleted, and the new one is downloaded.
The /imageonly option removes the device manager files for the existing image if the existing image is being removed or replaced. Only the software image (without the device manager files) is downloaded.
Using the /safe or /leave-old-sw option can cause the new image download to fail if there is insufficient flash space.
If you used the /leave-old-sw option and did not overwrite the old image when you downloaded the new one, you can remove the old image by using the delete privileged EXEC command. For more information, see the delete command.
If you leave the existing software in place before downloading the new image, an error results if the existing software prevents the new image from fitting onto flash memory.
After downloading a new image, enter the reload privileged EXEC command to begin using the new image, or specify the /reload or /force-reload option in the archive download-sw command.
Examples
This example shows how to download a new image from a TFTP server at 172.20.129.10 and to overwrite the image on the switch:
Switch# archive download-sw /overwrite tftp://172.20.129.10/test-image.tarThis example shows how to download only the software image from a TFTP server at 172.20.129.10 to the switch:
Switch# archive download-sw /imageonly tftp://172.20.129.10/test-image.tarThis example shows how to keep the old software version after a successful download:
Switch# archive download-sw /leave-old-sw tftp://172.20.129.10/test-image.tarRelated Commands
archive tar
Use the archive tar privileged EXEC command to create a tar file, to list files in a tar file, or to extract the files from a tar file.
archive tar {/create destination-url flash:/file-url} | {/table source-url} | {/xtract source-url flash:/file-url [dir/file...]}
Syntax Description
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
Filenames and directory names are case sensitive.
Image names are case sensitive.
Examples
This example shows how to create a tar file. The command writes the contents of the new-configs directory on the local flash device to a file named saved.tar on the TFTP server at 172.20.136.9:
Switch# archive tar /create tftp:172.20.136.9/saved.tar flash:/new-configsThis example shows how to display the contents of the saved.tar file that is in flash memory. The contents of the tar file appear on the screen.
Switch # archive tar /table tftp://172.20.136.9/saved.tarLoading saved.tar from 172.20.136.9 (via Vlan1):!info (247 bytes)c2950lre-i6l2q4-mz.121/ (directory)c2950lre-i6l2q4-mz.121/html/ (directory)c2950lre-i6l2q4-mz.121/html/homepage.htm (3990 bytes)!<output truncated>c2950lre-i6l2q4-mz.121/lre-bin/CISCO585-LRE_MC8051boot_01.03.00.bin (688bytes)c2950lre-i6l2q4-mz.121/lre-bin/CISCO585-LRE_vdslsngl_51.00.00.bin (8896bytes)!!c2950lre-i6l2q4-mz.121/pef22824.bin (32768 bytes)!!!!!!!c2950lre-i6l2q4-mz.121/info (247 bytes)info.ver (247 bytes)[OK - 4279808/8559616 bytes]This example shows how to extract the contents of a tar file on the TFTP server at 172.20.10.30. This command extracts just the new-configs directory into the root directory on the local flash file system. The remaining files in the saved.tar file are ignored.
Switch# archive tar /xtract tftp://172.20.10.30/saved.tar flash:/ new-configsRelated Commands
Downloads a new image to the switch.
Uploads an existing image on the switch to a server.
archive upload-sw
Use the archive upload-sw privileged EXEC command to upload an existing Long-Reach Ethernet (LRE) switch image to a server.
archive upload-sw [/version version_string] destination-url
This command is supported only on Catalyst 2950 LRE switches.
Syntax Description
Defaults
The switch uploads the currently running image from the flash: file system.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
Use the upload feature only if the files associated with the device manager have been installed with the existing image.
The files are uploaded in this sequence: info, the software image, the device manager files, LRE binary files, and info.ver. After these files are uploaded, the software creates the tar file.
Image names are case sensitive.
Examples
This example shows how to upload the currently running image to a TFTP server at 172.20.140.2:
Switch# archive upload-sw tftp://172.20.140.2/test-image.tarRelated Commands
Downloads a new image to a Catalyst 2950 LRE switch.
Creates a tar file, lists the files in a tar file, or extracts the files from a tar file.
auto qos voip
Use the auto qos voip interface configuration command to configure automatic quality of service (auto-QoS) for voice over IP (VoIP) within a QoS domain. Use the no form of this command to change the auto-QoS configuration settings to the standard-QoS defaults.
auto qos voip {cisco-phone | cisco-softphone | trust}
no auto qos voip
This command is available only if your switch is running the enhanced software image (EI).
Syntax Description
Defaults
Auto-QoS is disabled on all interfaces.
When auto-QoS is enabled, it uses the ingress packet label to categorize traffic and to configure the egress queues as summarized in Table 2-1.
Table 2-1 Traffic Types, Packet Labels, and Egress Queues
DSCP3
46
24, 26
48
56
34
—
CoS
5
3
6
7
4
—
CoS-to-Queue Map
5
3, 6, 7
4
2
0, 1
Egress Queue
1% WRR4 (queue 4)
70% WRR (queue 3)
20% WRR (queue 2)
20% WRR (queue 2)
10% WRR (queue 1)
1 STP = Spanning Tree Protocol
2 BPDU = bridge protocol data unit
3 DSCP = Differentiated Services Code Point
4 WRR = weighted round robin
Table 2-2 lists the auto-QoS configuration for the egress queues.
Command Modes
Interface configuration
Command History
12.1(12c)EA1
This command was introduced.
12.1(20)EA2
The cisco-softphone keyword was added, and the generated auto-QoS configuration changed.
Usage Guidelines
Use this command to configure the QoS that is appropriate for VoIP traffic within the QoS domain. The QoS domain includes the switch, the interior of the network, and the edge devices that can classify incoming traffic for QoS.
In releases earlier than Cisco IOS Release 12.2(20)EA2, auto-QoS configures the switch only for VoIP with Cisco IP Phones on switch ports.
In Cisco IOS Release 12.2(20)EA2 or later, auto-QoS configures the switch for VoIP with Cisco IP Phones and for VoIP with devices running the Cisco SoftPhone application. These releases support only Cisco IP SoftPhone Version 1.3(3) or later. Connected devices must use Cisco Call Manager Version 4 or later.
To take advantage of the auto-QoS defaults, you should enable auto-QoS before you configure other QoS commands. You can fine-tune the auto-QoS configuration after you enable auto-QoS.
Note
If this is the first port on which you have enabled auto-QoS, the auto-QoS-generated global configuration commands are executed followed by the interface configuration commands. If you enable auto-QoS on another port, only the auto-QoS-generated interface configuration commands for that port are executed.
When you enable the auto-QoS feature on the first interface, these automatic actions occur:
•
•
•
You can enable auto-QoS on static, dynamic-access, voice VLAN access, and trunk ports.
Note
After auto-QoS is enabled, do not modify a policy map or aggregate policer that includes AutoQoS in its name. If you need to modify the policy map or aggregate policer, make a copy of it, and change the copied policy map or policer. To use the new policy map instead of the generated one, remove the generated policy, and apply the new policy map.
To display the QoS configuration that is automatically generated when auto-QoS is enabled, enable debugging before you enable auto-QoS. Use the debug auto qos privileged EXEC command to enable auto-QoS debugging.
To disable auto-QoS on an interface, use the no auto qos voip interface configuration command. When you enter this command, the switch changes the auto-QoS settings to the standard-QoS default settings for that interface.
To disable auto-QoS on the switch and return to the default port trust state (untrusted), follow these steps:
1.
2.
•
•
•
Examples
This example shows how to enable auto-QoS and to trust the QoS labels received in incoming packets when the switch or router connected to a port is a trusted device:
Switch(config)# interface gigabitethernet0/1Switch(config-if)# auto qos voip trustThis example shows how to enable auto-QoS and to trust the QoS labels received in incoming packets when the device connected to a port is detected as a Cisco IP phone:
Switch(config)# interface fastethernet0/1Switch(config-if)# auto qos voip cisco-phoneThis example shows how to display the QoS configuration that is automatically generated when auto-QoS is enabled:
Switch# debug auto qosAutoQoS debugging is onSwitch# configure terminalEnter configuration commands, one per line. End with CNTL/Z.Switch(config)# interface fastethernet0/1Switch(config-if)# auto qos voip cisco-phone00:02:54:wrr-queue bandwidth 10 20 70 100:02:55:no wrr-queue cos-map00:02:55:wrr-queue cos-map 1 0 100:02:56:wrr-queue cos-map 2 2 400:02:57:wrr-queue cos-map 3 3 6 700:02:58:wrr-queue cos-map 4 500:02:59:mls qos map cos-dscp 0 8 16 26 32 46 48 5600:03:00:interface FastEthernet0/100:03:00: mls qos trust device cisco-phone00:03:00: mls qos trust cosSwitch(config-if)# interface fastethernet0/2Switch(config-if)# auto qos voip trust00:03:15:interface FastEthernet0/200:03:15: mls qos trust cosSwitch(config-if)#You can verify your settings by entering the show auto qos interface interface-id privileged EXEC command.
Related Commands
boot buffersize
Use the boot buffersize global configuration command to specify the size of the file system-simulated NVRAM in flash memory. The buffer holds a copy of the configuration file in memory. Use the no form of this command to return to the default setting.
boot buffersize size
no boot buffersize
This command is available only on Catalyst 2950 Long-Reach Ethernet (LRE) switches.
Syntax Description
Defaults
The default is 32 KB.
Command Modes
Global configuration
Command History
Usage Guidelines
The configuration file cannot be larger than the buffer size allocation.
You must reload the switch by using the reload privileged EXEC command for this command to take effect.
This command changes the setting of the CONFIG_BUFSIZE environment variable. For more information, see Appendix B, "Catalyst 2950 and 2955 Switch Boot Loader Commands."
Related Commands
boot config-file
Use the boot config-file global configuration command to specify the filename that the software uses to read and write a nonvolatile copy of the system configuration. Use the no form of this command to return to the default setting.
boot config-file flash:/file-url
no boot config-file
This command is available only on Catalyst 2950 Long-Reach Ethernet (LRE) switches.
Syntax Description
Defaults
The default configuration file is flash:config.text.
Command Modes
Global configuration
Command History
Usage Guidelines
Filenames and directory names are case sensitive.
This command changes the setting of the CONFIG_FILE environment variable. For more information, see Appendix B, "Catalyst 2950 and 2955 Switch Boot Loader Commands."
Related Commands
boot enable-break
Use the boot enable-break global configuration command to enable interrupting the automatic boot process on a Catalyst 2950 Long-Reach Ethernet (LRE) switch. Use the no form of this command to return to the default setting.
boot enable-break
no boot enable-break
This command is available only on Catalyst 2950 LRE switches.
Syntax Description
This command has no arguments or keywords.
Defaults
The automatic start up process cannot be interrupted by pressing the Break key on the console.
Command Modes
Global configuration
Command History
Usage Guidelines
When you enter this command, you can interrupt the automatic boot process by pressing the Break key on the console after the flash file system is initialized.
Note
This command changes the setting of the ENABLE_BREAK environment variable. For more information, see Appendix B, "Catalyst 2950 and 2955 Switch Boot Loader Commands."
Related Commands
boot helper
Use the boot helper global configuration command to dynamically load files during boot loader initialization to extend or to patch the functionality of the boot loader. Use the no form of this command to return to the default setting.
boot helper filesystem:/file-url ...
no boot helper
This command is available only on Catalyst 2950 Long-Reach Ethernet (LRE) switches.
Syntax Description
Defaults
No helper files are loaded.
Command Modes
Global configuration
Command History
Usage Guidelines
Filenames and directory names are case sensitive.
This command changes the setting of the HELPER environment variable. For more information, see Appendix B, "Catalyst 2950 and 2955 Switch Boot Loader Commands."
Related Commands
boot helper-config-file
Use the boot helper-config-file global configuration command to specify the name of the configuration file to be used by the Cisco IOS helper image. If this is not set, the file specified by the CONFIG_FILE environment variable is used by all versions of the software that are loaded. This variable is used only for internal development and testing. Use the no form of this command to return to the default setting.
boot helper-config-file filesystem:/file-url
no boot helper-config file
This command is available only on Catalyst 2950 Long-Reach Ethernet (LRE) switches.
Syntax Description
filesystem:
Alias for a flash file system. Use flash: for the system board flash device.
/file-url
The path (directory) and helper configuration file to load.
Defaults
No helper configuration file is specified.
Command Modes
Global configuration
Command History
Usage Guidelines
Filenames and directory names are case sensitive.
This command changes the setting of the HELPER_CONFIG_FILE environment variable. For more information, see Appendix B, "Catalyst 2950 and 2955 Switch Boot Loader Commands."
Related Commands
boot manual
Use the boot manual global configuration command to enable starting the Catalyst 2950 Long-Reach Ethernet (LRE) switch manually during the next power on cycle. Use the no form of this command to return to the default setting.
boot manual
no boot manual
This command is available only on Catalyst 2950 LRE switches.
Syntax Description
This command has no arguments or keywords.
Defaults
During the next power on cycle, you cannot manually start an LRE switch.
Command Modes
Global configuration
Command History
Usage Guidelines
The next time you restart the system, the switch is in boot loader mode, which is shown by the switch: prompt. To power on the system, use the boot boot loader command, and specify the name of the bootable image.
This command changes the setting of the MANUAL_BOOT environment variable. For more information, see Appendix B, "Catalyst 2950 and 2955 Switch Boot Loader Commands."
Related Commands
boot private-config-file
Use the boot private-config-file global configuration command to specify the filename that the software uses to read and write a nonvolatile copy of the private configuration. Use the no form of this command to return to the default setting.
boot private-config-file filename
no boot private-config-file
Syntax Description
Defaults
The default configuration file is private-config.text.
Command Modes
Global configuration
Command History
Usage Guidelines
Only the software can read and write a copy of the private configuration file. You cannot read, write, delete, or display a copy of this file.
Filenames are case sensitive.
Examples
This example shows how to specify the name of the private configuration file as pconfig:
Switch(config)# boot private-config-file pconfigRelated Commands
boot system
Use the boot system global configuration command to specify the software image to load during the next power on cycle. Use the no form of this command to return to the default setting.
boot system filesystem:/file-url ...
no boot system
This command is available only on Catalyst 2950 Long-Reach Ethernet (LRE) switches.
Syntax Description
filesystem:
Alias for a flash file system. Use flash: for the system board flash device.
/file-url
The path (directory) and name of a bootable image. Separate image names with a semicolon.
Defaults
The switch attempts to automatically power on the system by using information in the BOOT environment variable. If this variable is not set, the switch attempts to load and execute the first executable image it can by performing a recursive, depth-first search throughout the flash file system. In a depth-first search of a directory, each encountered subdirectory is completely searched before the switch continues to search in the original directory.
Command Modes
Global configuration
Command History
Usage Guidelines
Filenames and directory names are case sensitive.
If you are using the archive download-sw privileged EXEC command to maintain system images, you do not ever need to use the boot system command. The boot system command is automatically manipulated to load the downloaded image.
This command changes the setting of the BOOT environment variable. For more information, see Appendix B, "Catalyst 2950 and 2955 Switch Boot Loader Commands."
Related Commands
channel-group
Use the channel-group interface configuration command to assign an Ethernet interface to an EtherChannel group and to enable an EtherChannel mode. Use the no form of this command to remove an Ethernet interface from an EtherChannel group.
channel-group channel-group-number mode {active | {auto [non-silent]} | {desirable [non-silent]} | on | passive}
no channel-group
PAgP modes:
channel-group channel-group-number mode {{auto [non-silent]} | {desirable [non-silent}}LACP modes:
channel-group channel-group-number mode {active | passive}On mode:
channel-group channel-group-number mode onSyntax Description
Defaults
No channel groups are assigned.
There is no default mode.
Command Modes
Interface configuration
Command History
12.1(6)EA2
This command was introduced. It replaced the port group command.
12.1(12c)EA1
The active and passive keywords were added.
Usage Guidelines
You must specify the mode when entering this command. If the mode is not entered, an Ethernet interface is not assigned to an EtherChannel group, and an error message appears.
You do not have to create a port-channel interface before assigning a physical interface to a channel group. A port-channel interface is created automatically when the channel group gets its first physical interface.
You do not have to disable the IP address that is assigned to a physical interface that is part of a channel group, but we highly recommend that you do so.
You can create port channels by entering the interface port-channel global configuration command or when the channel group gets its first physical interface assignment. The port channels are not created at runtime or dynamically.
Any configuration or attribute changes you make to the port-channel interface are propagated to all interfaces within the same channel group as the port channel (for example, configuration changes are also propagated to the physical interfaces that are not part of the port channel, but are part of the channel group).
In the on mode, a PAgP EtherChannel exists only when a port group in on mode is connected to another port group in on mode.
If you do not specify non-silent with the auto or desirable mode, silent is assumed. The silent mode is used when the switch is connected to a device that is not PAgP-capable and seldom, if ever, sends packets. An example of a silent partner is a file server or a packet analyzer that is not generating traffic. In this case, running PAgP on a physical port prevents that port from ever becoming operational; however, it allows PAgP to operate, to attach the interface to a channel group, and to use the interface for transmission. Both ends of the link cannot be set to silent.
Note
Caution
Do not configure a port that is an active or a not-yet-active member of an EtherChannel as an IEEE 802.1x port. If you try to enable IEEE 802.1x authentication on an EtherChannel port, an error message appears, and IEEE 802.1x authentication is not enabled.
Examples
This example shows how to add an interface to the EtherChannel group specified as channel group 1:
Switch(config)# interface gigabitethernet0/1Switch(config-if)# channel-group 1 mode onThis example shows how to set an Etherchannel into PAgP mode:
Switch(config-if)# channel-group 1 mode autoCreating a port-channel interface Port-channel 1This example shows how to set an Etherchannel into LACP mode:
Switch(config-if)# channel-group 1 mode passiveCreating a port-channel interface Port-channel 1You can verify your settings by entering the show etherchannel or show running-config privileged EXEC command.
Related Commands
channel-protocol
Use the channel-protocol interface configuration command to configure an EtherChannel for the Port Aggregation Protocol (PAgP) or Link Aggregation Control Protocol (LACP). Use the no form of this command to disable PAgP or LACP on the EtherChannel.
channel-protocol {lacp | pagp}
no channel-protocol
Syntax Description
lacp
Configure an EtherChannel with the LACP protocol.
pagp
Configure an EtherChannel with the PAgP protocol.
Defaults
No protocol is assigned to the EtherChannel.
Command Modes
Interface configuration
Command History
Usage Guidelines
Use the channel-protocol command only to restrict a channel to LACP or PAgP.
You must use the channel-group interface command to configure the EtherChannel parameters. The channel-group command can also set the EtherChannel for a channel.
Note
Caution
Examples
This example shows how to set an EtherChannel into PAgP mode:
Switch(config-if)# channel-protocol pagpThis example shows how to set an EtherChannel into LACP mode:
Switch(config-if)# channel-protocol lacpYou can verify your settings by entering the show running-config privileged EXEC command.
Related Commands
class
Use the class policy-map configuration command to define a traffic classification for the policy to act on using the class-map name or access group. Use the no form of this command to delete an existing class map.
class class-map-name [access-group name acl-index-or-name]
no class class-map-name
This command is available only if your switch is running the enhanced software image (EI).
Syntax Description
Defaults
No policy-map class maps are defined.
Command Modes
Policy-map configuration
Command History
Usage Guidelines
Before you use the class command, use the policy-map global configuration command to identify the policy map and to enter policy-map configuration mode. After you specify a policy map, you can configure a policy for new classes or modify a policy for any existing classes in that policy map. You attach the policy map to an interface by using the service-policy interface configuration command; however, you cannot attach one that uses an ACL classification to the egress direction.
The class name that you specify in the policy map ties the characteristics for that class to the class map and its match criteria as configured by using the class-map global configuration command.
The class command performs the same function as the class-map global configuration command. Use the class command when a new classification, which is not shared with any other ports, is needed. Use the class-map command when the map is shared among many ports.
Note
After entering the class command, you enter policy-map class configuration mode. These configuration commands are available:
•
•
•
•
•
To return to policy-map configuration mode, use the exit command. To return to privileged EXEC mode, use the end command.
Note
Examples
This example shows how to create a policy map named policy1. When attached to the ingress port, it matches all the incoming traffic defined in class1 and polices the traffic at an average rate of 1 Mbps and bursts at 131072 bytes. Traffic exceeding the profile is dropped.
Switch(config)# policy-map policy1Switch(config-pmap)# class class1Switch(config-pmap-c)# police 1000000 131072 exceed-action dropSwitch(config-pmap-c)# exitSwitch(config-pmap)#You can verify your settings by entering the show policy-map privileged EXEC command.
Related Commands
class-map
Use the class-map global configuration command to create a class map to be used for matching packets to the class whose name you specify and to enter class-map configuration mode. Use the no form of this command to delete an existing class map and to return to global configuration mode.
class-map class-map-name [match-all]
no class-map class-map-name [match-all]
This command is available only if your switch is running the enhanced software image (EI).
Syntax Description
class-map-name
Name of the class map.
match-all
(Optional) Perform a logical-AND of all matching statements under this class map. All criteria in the class map must be matched.
Defaults
No class maps are defined.
Command Modes
Global configuration
Command History
Usage Guidelines
Use this command to specify the name of the class for which you want to create or modify class-map match criteria and to enter class-map configuration mode. In this mode, you can enter one match command to configure the match criteria for this class.
The class-map command and its subcommands are used to define packet classification and marking as part of a globally named service policy applied on a per-interface basis.
In quality of service (QoS) class-map configuration mode, these configuration commands are available:
•
•
•
Only one match criterion per class map is supported. For example, when defining a class map, only one match command can be entered.
Only one access control list (ACL) can be configured in a class map. The ACL can have multiple access control entries (ACEs).
Note
Note
Examples
This example shows how to configure the class map named class1. class1 has one match criteria, which is a numbered ACL.
Switch(config)# access-list 103 permit tcp any any eq 80Switch(config)# class-map class1Switch(config-cmap)# match access-group 103Switch(config-cmap)# exitYou can verify your settings by entering the show class-map privileged EXEC command.
Related Commands
clear controllers ethernet-controller
Use the clear controllers ethernet-controller privileged EXEC command to clear the Ethernet link transmit and receive statistics for a switch port and for a Long-Reach Ethernet (LRE) customer premises equipment (CPE) device.
clear controllers ethernet-controller interface-id [cpe [port port-id]]
Syntax Description
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
The CPE Ethernet link is the connection between the CPE Ethernet port and the remote Ethernet device (such as a PC) connected to it. It is not the link between the switch LRE port and the LRE CPE device.
It takes the switch several seconds to clear the CPE Ethernet ports. The CPE Ethernet ports on CPE devices take longer to clear than all the other port types.
If you enter the clear controllers ethernet-controller privileged EXEC command without specifying an interface-id, the switch clears the Ethernet link statistics for all ports on the switch. If you specify an an interface, the switch clears the Ethernet link statistics for the specified port.
On a Catalyst 2950 LRE switch, if you use the cpe keyword, the switch clears the Ethernet statistics of the LRE chipset and of all these CPE Ethernet ports:
•
•
If you enter the cpe port port-id keywords, the switch clears the Ethernet counters of the specified CPE Ethernet port.
Note
Examples
This example shows how to clear the Ethernet link statistics for an LRE port:
Switch# clear controllers ethernet-controller longreachethernet0/1This example clears the Ethernet statistics for all the CPE Ethernet ports on a Cisco 585 LRE CPE:
Switch# clear controllers ethernet-controller longreachethernet0/1 cpeYou can verify that information was deleted by entering the show controllers ethernet-controller user EXEC command.
Related Commands
Displays per-interface transmit and receive statistics read from the hardware, the interface internal registers, the statistics read from LRE and CPE ports.
clear controllers lre
Use the clear controllers lre user EXEC command to reset an Long-Reach Ethernet (LRE) switch interface or a Cisco LRE customer premises equipment (CPE) device interface.
clear controllers lre {local link | remote [link | micro]} interface-id
This command is available only on Catalyst 2950 LRE switches.
Syntax Description
Defaults
No default is defined.
Command Modes
User EXEC
Command History
Usage Guidelines
Use this command to reset a questionable local or remote interface.
The clear controllers lre remote micro command is not supported on the Cisco 575 LRE CPE and the Cisco 576 LRE 997 CPE devices.
Examples
This example shows how to reset the local LRE interfaces on the switch:
Switch> clear controllers lre local linkThis example shows how to reset the Cisco 575 LRE, Cisco 576 LRE 997 CPE, and the Cisco 585 LRE CPE devices connected to the switch:
Switch> clear controllers lre remote linkThis example shows how to reset the Cisco 585 LRE CPE micro-controller connected to the switch:
Switch> clear controllers lre remote microRelated Commands
clear controllers lre link monitor
Use the clear controllers lre link monitor privileged EXEC command to clear Long-Reach Ethernet (LRE) link monitor data.
clear controllers lre link monitor interface-id
This command is available only on Catalyst 2950 LRE switches.
Syntax Description
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
This command clears all collected link monitor data. New entries are added when a new polling cycle starts.
Examples
This example shows how to clear link monitor data on an LRE port:
Switch# clear controllers lre link monitor longreachethernet0/2Related Commands
clear controllers lre log
Use the clear controllers lre log privileged EXEC command to clear the history of link, configuration, and timer events for a specific Long-Reach Ethernet (LRE) port or for all switch LRE ports.
clear controllers lre log [interface-id]
This command is available only on Catalyst 2950 LRE switches.
Syntax Description
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
Use the clear controllers lre log command without specifying a switch LRE port to delete the history of events on all LRE ports.
Examples
This example shows how to delete the history of events on an LRE switch port:
Switch# clear controllers lre log longreachethernet0/3You can verify that the information was deleted by entering the show controllers lre log privileged EXEC command.
Related Commands
Sets the LRE logging level.
Displays the history of link, configuration, and timer events for a LRE specific switch port or for all LRE switch ports.
clear interface
Use the clear interface privileged EXEC command to clear the hardware logic on an interface or a VLAN.
clear interface {interface-id | vlan vlan-id}
Syntax Description
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to clear the hardware logic on an interface:
Switch# clear interface gigabitethernet0/1This example shows how to clear the hardware logic on a specific VLAN:
Switch# clear interface vlan 5You can verify that the interface-reset counter for an interface is incremented by entering the show interfaces privileged EXEC command.
clear lacp
Use the clear lacp privileged EXEC command to clear Link Aggregration Control Protocol (LACP) channel-group information.
clear lacp {channel-group-number | counters}
Syntax Description
Defaults
This command has no default setting.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to clear channel-group information for a specific group:
Switch# clear lacp 4This example shows how to clear channel-group traffic counters:
Switch# clear lacp countersYou can verify that the information was deleted by entering the show lacp privileged EXEC command.
Related Commands
clear lre rate selection
Use the clear lre rate selection privileged EXEC command to reset the current rate selection setting and to restart rate selection for a specific Long-Reach Ethernet (LRE) port or for all switch LRE ports.
clear lre rate selection [lock] [interface-id]
This command is available only on Catalyst 2950 LRE switches.
Syntax Description
lock
(Optional) Rate selection runs on all ports that have rate selection enabled, including ports that are locked.
interface-id
(Optional) ID of an LREs witch port.
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
If you enter the lock keyword or specify an interface, the switch runs rate selection on all LRE switch ports that have rate selection enabled, except those ports with locked profiles. If you enter the lock keyword, the switch runs rate selection on all profiles, including those that are locked.
Examples
This example shows how to reset the rate selection setting and to restart rate selection on an LRE port:
Switch# clear lre rate selection longreachethernet0/1This example shows how to rerun rate selection on all ports, including any locked ports:
Switch# clear lre rate selection lockThis example shows how to reset and to restart rate selection on an LRE port, overriding the locked status:
Switch# clear lre rate selection lock longreachethernet0/2Related Commands
Enables rate selection on an LRE specific port
Assigns a rate selection sequence for a specific LRE port.
Assigns a rate selection sequence for the entire LRE switch.
clear mac address-table
Use the clear mac address-table privileged EXEC command to delete from the MAC address table a specific dynamic address, all dynamic addresses on a particular interface, or all dynamic addresses on a particular VLAN. This command also clears the MAC address notification global counters.
clear mac address-table {dynamic [address mac-addr | interface interface-id | vlan vlan-id] | notification}
Note
Syntax Description
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to remove a specific dynamic address from the MAC address table:
Switch# clear mac address-table dynamic address 0008.0070.0007You can verify that the information was deleted by entering the show mac address-table privileged EXEC command.
Related Commands
clear pagp
Use the clear pagp privileged EXEC command to clear Port Aggregation Protocol (PAgP) channel-group information.
clear pagp {channel-group-number [counters] | counters}
Syntax Description
Defaults
This command has no default setting.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to clear channel-group information for a specific group:
Switch# clear pagp 4This example shows how to clear channel-group traffic counters:
Switch# clear pagp countersYou can verify that the information was deleted by entering the show pagp privileged EXEC command.
Related Commands
clear port-security
Use the clear port-security privileged EXEC command to delete from the MAC address table all secure addresses, all configured secure addresses, or a specific or all dynamic or sticky secure address on an interface or on the switch.
clear port-security {all | configured | dynamic | sticky} [address mac-address] | [interface interface-id]
Syntax Description
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
12.1(11)EA1
This command was introduced.
12.1(14)EA1
The all and configured keywords were added.
Usage Guidelines
If you enter the clear port-security all privileged EXEC command, the switch removes all secure MAC addresses from the MAC address table.
If you enter the clear port-security configured address mac-address command, the switch removes the specified secure MAC address from the MAC address table.
If you enter the clear port-security dynamic interface interface-id command, the switch removes all dynamic secure MAC addresses on an interface from the MAC address table.
If you enter the clear port-security sticky command, the switch removes all sticky secure MAC addresses from the MAC address table.
Examples
This example shows how to remove all secure addresses from the MAC address table:
Switch# clear port-security allThis example shows how to remove a configured secure address from the MAC address table:
Switch# clear port-security configured address 0008.0070.0007This example shows how to remove all the dynamic secure addresses learned on a specific interface:
Switch# clear port-security dynamic interface fastethernet0/1This example shows how to remove all the sticky secure addresses from the address table:
Switch# clear port-security stickyYou can verify that the information was deleted by entering the show port-security privileged EXEC command.
Related Commands
Displays the port security settings for an interface or for the switch.
Enables port security on an interface.
switchport port-security mac-address mac-address
Configures secure MAC addresses.
switchport port-security maximum value
Configures a maximum number of secure MAC addresses on a secure interface.
clear spanning-tree counters
Use the clear spanning-tree counters privileged EXEC command to clear the spanning-tree counters.
clear spanning-tree counters [interface interface-id]
Syntax Description
interface interface-id
(Optional) Clear all spanning-tree counters on the specified interface. If interface-id is not specified, spanning-tree counters are cleared for all interfaces.
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to clear spanning-tree counters for all interfaces:
Switch# clear spanning-tree countersRelated Commands
clear spanning-tree detected-protocols
Use the clear spanning-tree detected-protocols privileged EXEC command to restart the protocol migration process (force the renegotiation with neighboring switches) on all interfaces or on the specified interface.
clear spanning-tree detected-protocols [interface interface-id]
Syntax Description
Command Modes
Privileged EXEC
Command History
12.1(9)EA1
This command was introduced.
12.1(20)EA2
This command was added to the SI.
Usage Guidelines
A switch running the rapid per-VLAN spanning-tree plus (rapid-PVST+) protocol or the Multiple Spanning Tree Protocol (MSTP) supports a built-in protocol migration mechanism that enables it to interoperate with legacy IEEE 802.1D switches. If a rapid-PVST+ switch or an MSTP switch receives a legacy IEEE 802.1D configuration bridge protocol data unit (BPDU) with the protocol version set to 0, it sends only IEEE 802.1D BPDUs on that port. A multiple spanning-tree (MST) switch can also detect that a port is at the boundary of a region when it receives a legacy BPDU, an MST BPDU (version 3) associated with a different region, or an RST BPDU (version 2).
However, the switch does not automatically revert to the rapid-PVST+ or the MSTP mode if it no longer receives IEEE 802.1D BPDUs because it cannot determine whether the legacy switch has been removed from the link unless the legacy switch is the designated switch. Use the clear spanning-tree detected-protocols command in this situation.
Examples
This example shows how to restart the protocol migration process on an interface:
Switch# clear spanning-tree detected-protocols interface fastethernet0/1clear vmps statistics
Use the clear vmps statistics privileged EXEC command to clear the statistics maintained by the VLAN Query Protocol (VQP) client.
clear vmps statistics
Syntax Description
This command has no arguments or keywords.
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to clear VLAN Membership Policy Server (VMPS) statistics:
Switch# clear vmps statisticsYou can verify that the information was deleted by entering the show vmps statistics privileged EXEC command.
Related Commands
show vmps statistics
Displays the VQP version, reconfirmation interval, retry count, VMPS IP addresses, and the current and primary servers.
clear vtp counters
Use the clear vtp counters privileged EXEC command to clear the VLAN Trunking Protocol (VTP) and pruning counters.
clear vtp counters
Syntax Description
This command has no arguments or keywords.
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to clear the VTP counters:
Switch# clear vtp countersYou can verify that the information was deleted by entering the show vtp counters privileged EXEC command.
Related Commands
show vtp counters
Displays general information about the VTP management domain, status, and counters.
cluster commander-address
You do not need to enter this command. The command switch automatically provides its MAC address to member switches when these switches join the cluster. The member switch adds this information and other cluster information to its running configuration file. Enter the no form of this global configuration command from the member switch service port to remove it from a cluster only during debugging or recovery procedures.
cluster commander-address mac-address [member number name name]
no cluster commander-address
Syntax Description
Defaults
The switch is not a member of any cluster.
Command Modes
Global configuration
Command History
Usage Guidelines
A cluster member can have only one command switch.
The member switch retains the identity of the command switch during a system reload by using the mac-address parameter.
You can enter the no form on a member switch to remove it from the cluster during debugging or recovery procedures. You would normally use this command from the member switch consoleservice port only when the member has lost communication with the command switch. With normal switch configuration, we recommend that you remove member switches only by entering the no cluster member n global configuration command on the command switch.
When a standby command-switch becomes active (becomes the command switch), it removes the cluster commander-address line from its configuration.
Examples
This is an example of text from the running configuration of a cluster member:
Switch(config)# show running-config<output truncated>cluster commander-address 00e0.9bc0.a500 member 4 name my_cluster<output truncated>This example shows how to remove a member from the cluster by using the cluster member console:
Switch# configure terminalEnter configuration commands, one per line. End with CNTL/Z.Switch(config)# no cluster commander-addressYou can verify your settings by entering the show cluster privileged EXEC command.
Related Commands
cluster discovery hop-count
Use the cluster discovery hop-count global configuration command on the command switch to set the hop-count limit for extended discovery of candidate switches. Use the no form of this command to return to the default setting.
cluster discovery hop-count number
no cluster discovery hop-count
Syntax Description
number
Number of hops from the cluster edge that the command switch limits the discovery of candidates. The range is 1 to 7.
Defaults
The hop count is set to 3.
Command Modes
Global configuration
Command History
Usage Guidelines
Enter this command only on the command switch. This command does not operate on member switches.
If the hop count is set to 1, it disables extended discovery. The command switch discovers only candidates that are one hop from the edge of the cluster. The edge of the cluster is the point between the last discovered member switch and the first discovered candidate switch.
Examples
This example shows how to set the hop count limit to 4. This command is entered on the command switch.
Switch(config)# cluster discovery hop-count 4You can verify your settings by entering the show cluster privileged EXEC command on the command switch.
Related Commands
Displays the cluster status and a summary of the cluster to which the switch belongs.
Displays a list of candidate switches.
cluster enable
Use the cluster enable global configuration command on a command-capable switch to enable it as the cluster command switch, assign a cluster name, and optionally assign a member number to it. Use the no form of this command to remove all members and make the command switch a candidate switch.
cluster enable name [command-switch-member-number]
no cluster enable
Syntax Description
Defaults
The switch is not a command switch.
No cluster name is defined.
The member number is 0 when this is the command switch.
Command Modes
Global configuration
Command History
Usage Guidelines
This command runs on any command-capable switch that is not part of any cluster. This command fails if a device is already configured as a member of the cluster.
You must name the cluster when you enable the command switch. If the switch is already configured as the command switch, this command changes the cluster name if it is different from the previous name.
Examples
This example shows how to enable the command switch, name the cluster, and set the command switch member number to 4:
Switch(config)# cluster enable Engineering-IDF4 4You can verify your settings by entering the show cluster privileged EXEC command on the command switch.
cluster holdtime
Use the cluster holdtime global configuration command on the command switch to set the duration in seconds before a switch (either the command or member switch) declares the other switch down after not receiving heartbeat messages. Use the no form of this command to return to the default setting.
cluster holdtime holdtime-in-secs
no cluster holdtime
Syntax Description
holdtime-in-secs
Duration in seconds before a switch (either a command or member switch) declares the other switch down. The range is 1 to 300 seconds.
Defaults
The holdtime is 80 seconds.
Command Modes
Global configuration
Command History
Usage Guidelines
Use this command with the cluster timer global configuration command only on the command switch. The command switch propagates the values to all its cluster members so that the setting is consistent among all switches in the cluster.
The holdtime is typically set as a multiple of the interval timer (cluster timer). For example, it takes (holdtime-in-secs divided by interval-in-secs) number of heartbeat messages to be missed in a row to declare a switch down.
Examples
This example shows how to change the interval timer and the duration on the command switch:
Switch(config)# cluster timer 3Switch(config)# cluster holdtime 30You can verify your settings by entering the show cluster privileged EXEC command.
Related Commands
Displays the cluster status and a summary of the cluster to which the switch belongs.
cluster management-vlan
Use the cluster management-vlan global configuration command on the command switch to change the management VLAN for the entire cluster. Use the no form of this command to change the management VLAN to VLAN 1.
cluster management-vlan n
no cluster management-vlan
Syntax Description
Defaults
The default management VLAN is VLAN 1.
Command Modes
Global configuration
Command History
Usage Guidelines
Enter this command only on the command switch. This command changes the management VLAN of the command switch and member switches. Member switches must have either a trunk connection or connection to the new command-switch management VLAN to maintain communication with the command switch.
This command is not written to the configuration file.
Examples
This example shows how to change the management VLAN to VLAN 5 on the entire cluster:
Switch(config)# cluster management-vlan 5You can verify your settings by entering the show interfaces vlan vlan-id privileged EXEC command.
Related Commands
Displays the administrative and operational status of a switching (nonrouting) port.
cluster member
Use the cluster member global configuration command on the command switch to add members to a cluster. Use the no form of this command to remove members from the cluster.
cluster member [n] mac-address H.H.H [password enable-password] [vlan vlan-id]
no cluster member n
Syntax Description
Defaults
A newly enabled command switch has no associated cluster members.
Command Modes
Global configuration
Command History
Usage Guidelines
Enter this command only on the command switch to add a member to or remove a member from the cluster. If you enter this command on a switch other than the command switch, the switch rejects the command and displays an error message.
You must enter a member number to remove a switch from the cluster. However, you do not need to enter a member number to add a switch to the cluster. The command switch selects the next available member number and assigns it to the switch that is joining the cluster.
You must enter the enable password of the candidate switch for authentication when it joins the cluster. The password is not saved in the running or startup configuration. After a candidate switch becomes a member of the cluster, its password becomes the same as the command-switch password.
If a switch does not have a configured host name, the command switch appends a member number to the command-switch host name and assigns it to the member switch.
If you do not specify a VLAN ID, the command switch automatically chooses a VLAN and adds the candidate to the cluster.
Examples
This example shows how to add a switch as member 2 with MAC address 00E0.1E00.2222 and the password key to a cluster. The command switch adds the candidate to the cluster through VLAN 3.
Switch(config)# cluster member 2 mac-address 00E0.1E00.2222 password key vlan 3This example shows how to add a switch with MAC address 00E0.1E00.3333 to the cluster. This switch does not have a password. The command switch selects the next available member number and assigns it to the switch joining the cluster.
Switch(config)# cluster member mac-address 00E0.1E00.3333You can verify your settings by entering the show cluster members privileged EXEC command on the command switch.
Related Commands
Displays the cluster status and a summary of the cluster to which the switch belongs.
Displays a list of candidate switches.
Displays information about the cluster members.
cluster run
Use the cluster run global configuration command to enable clustering on a switch. Use the no form of this command to disable clustering on a switch.
cluster run
no cluster run
Defaults
Clustering is enabled on all switches.
Command Modes
Global configuration
Command History
Usage Guidelines
When you enter the no cluster run command on a command switch, the command switch is disabled. Clustering is disabled, and the switch cannot become a candidate switch.
When you enter the no cluster run command on a member switch, it is removed from the cluster. Clustering is disabled, and the switch cannot become a candidate switch.
When you enter the no cluster run command on a switch that is not part of a cluster, clustering is disabled on this switch. This switch cannot then become a candidate switch.
Examples
This example shows how to disable clustering on the command switch:
Switch(config)# no cluster runYou can verify that clustering is disabled by entering the show cluster privileged EXEC command.
Related Commands
Displays the cluster status and a summary of the cluster to which the switch belongs.
cluster standby-group
Use the cluster standby-group global configuration command to enable command switch redundancy by binding the Hot Standby Router Protocol (HSRP) standby group to the cluster. Use the no form of this command to unbind the cluster from the HSRP standby group.
cluster standby-group HSRP-group-name
no cluster standby-group
Syntax Description
HSRP-group-name
Name of the HSRP group that is bound to the cluster. The group name is limited to 32 characters.
Defaults
The cluster is not bound to any HSRP group.
Command Modes
Global configuration
Command History
Usage Guidelines
You must enter this command only on the command switch. If you enter it on a member switch, an error message appears.
The command switch propagates the cluster-HSRP binding information to all members. Each member switch stores the binding information in its NVRAM.
The HSRP group name must be a valid standby group; otherwise, the command entry produces an error.
Use the same group name on all members of the HSRP standby group that is to be bound to the cluster. Use the same HSRP group name on all cluster-HSRP capable members for the HSRP group that is to be bound. (When not binding a cluster to an HSRP group, you can use different names on the cluster command and the member switches.)
Examples
This example shows how to bind the HSRP group named my_hsrp to the cluster. This command is entered on the command switch.
Switch(config)# cluster standby-group my_hsrpThis example shows the error message when this command is entered on a command switch and the specified HSRP standby group does not exist:
Switch(config)# cluster standby-group my_hsrp%ERROR:Standby (my_hsrp) group does not existThis example shows the error message when this command is entered on a member switch:
Switch(config)# cluster standby-group my_hsrp%ERROR:This command runs on a cluster command switchYou can verify your settings by entering the show cluster privileged EXEC command.
Related Commands
Displays the cluster status and a summary of the cluster to which the switch belongs.
show standby
Displays standby group information.
standby ip
Enables HSRP on the interface.
cluster timer
Use the cluster timer global configuration command on the command switch to set the interval in seconds between heartbeat messages. Use the no form of this command to return to the default setting.
cluster timer interval-in-secs
no cluster timer
Syntax Description
Defaults
The interval is 8 seconds.
Command Modes
Global configuration
Command History
Usage Guidelines
Use this command with the cluster holdtime global configuration command only on the command switch. The command switch propagates the values to all its cluster members so that the setting is consistent among all switches in the cluster.
The holdtime is typically set as a multiple of the heartbeat interval timer (cluster timer). For example, it takes (holdtime-in-secs divided by the interval-in-secs) number of heartbeat messages to be missed in a row to declare a switch down.
Examples
This example shows how to change the heartbeat interval timer and the duration on the command switch:
Switch(config)# cluster timer 3Switch(config)# cluster holdtime 30You can verify your settings by entering the show cluster privileged EXEC command.
Related Commands
Displays the cluster status and a summary of the cluster to which the switch belongs.
controller longreachethernet
Use the controller longreachethernet global configuration command to enter the controller configuration mode.
controller longreachethernet ctrlr-number
This command is available only on Catalyst 2950 Long-Reach Ethernet (LRE) switches.
Syntax Description
ctrlr-number
LRE controller number. Controller numbers are device specific. The range is 0 to 2 on a 24-port LRE switch and 0 on an 8-port LRE switch.
Defaults
No default is defined.
Command Modes
Global configuration
Command History
Usage Guidelines
Use this command to enter the controller configuration mode. An LRE controller is the LRE chipset in the switch.
Examples
This example shows how to enter the controller configuration mode for controller 0:
Switch(config)# controller longreachethernet 0Switch(config-controller)#Related Commands
Configures upgrades on either end of an LRE link.
Prevents an upgrade of the local customer premises equipment (CPE) controller and all remote CPE devices connected to it.
cpe duplex
Use the cpe duplex interface configuration command to specify the duplex mode of operation for all customer premises equipment (CPE) ports. Use the no form of this command to return to the default setting.
cpe duplex {{auto | full | half} [port port-id]}
no cpe duplex {{auto | full | half} [port port-id]}
This command is available only on Catalyst 2950 Long-Reach Ethernet (LRE) switches.
Syntax Description
Defaults
The default duplex mode is half.
Command Modes
Interface configuration
Command History
Usage Guidelines
Use the cpe duplex full command to set the duplex mode to full for all the CPE Ethernet ports. Use the auto keyword to set the CPE Ethernet ports to autonegotiate, and use the half keyword to force the duplex mode to half for all the CPE Ethernet ports.
If you do not enter the port keyword, the duplex setting is applied to all the CPE Ethernet ports. If you enter the port port-id keywords, the setting is applied to the specified CPE Ethernet port and overrides any global speed settings.
Use the cpe duplex full port 2 command to set the duplex mode of port 2 on a CPE device to full duplex. If you enter both a switch-wide command, such as the cpe duplex full command, and a port-specific commands, such as the cpe duplex full port 2 command, the switch adds both the configuration file, and the port-specific command takes priority over the switch-wide command.
Examples
This example show how to set the CPE device to autonegotiate:
Switch# configure terminalSwitch(config)# interface longreachethernet0/2Switch(config-if)# cpe duplex autoThis example shows how to set a port on a Cisco 585 LRE CPE to full-duplex mode:
Switch# configure terminalSwitch(config)# interface longreachethernet0/3Switch(config-if)# cpe duplex full port 3This example shows how to restore a port on a Cisco 585 LRE CPE to the default mode of half duplex:
Switch# configure terminalSwitch(config)# interface longreachethernet0/3Switch(config-if)# no cpe duplex full port 3This example shows how the cpe duplex {auto | full | half} port port-id command works with the cpe duplex {auto | full | half} command. Port 1 is set to full duplex, port 2 is set to half duplex, and the remainder of the ports are set to autonegotiate.
Switch# configure terminalSwitch(config)# interface longreachethernet0/4Switch(config-if)# cpe duplex autoSwitch(config-if)# cpe duplex full port 1Switch(config-if)# cpe duplex half port 2After the commands in the previous example are entered, this example shows how to set a port to autonegotiate:
Switch(config-if)# no cpe duplex full port 1Related Commands
Specifies the CPE port speed settings.
show interfaces cpe
Displays CPE Ethernet ports connection, speed, or duplex status.
cpe protected
Use the cpe protected interface configuration command to restrict data traffic to individual ports on Cisco 585 LRE customer premises equipment (CPE) ports. Use the no form of this command to allow different ports on the same CPE device to exchange data directly.
cpe protected [port port-id]
no cpe protected [port port-id]
This command is available only on Catalyst 2950 Long-Reach Ethernet (LRE) switches.
Syntax Description
Defaults
Traffic is not restricted to specific ports.
Command Modes
Interface configuration
Command History
Usage Guidelines
Even though you can protect an LRE interface by using the switchport protected interface configuration command, this command does not protect individual CPE Ethernet ports. Use the cpe protected command to ensure that data traffic from one CPE port is not accessed on any of the other three ports. Use the cpe protected command to restrict CPE traffic, either at the CPE device level or at the individual port level for data security. Use the cpe protected command without specifying a CPE port to protect data for all applicable CPE ports. Use the cpe protected port port-id command to protect a specific CPE Ethernet port.
When using this feature, always specify a minimum of two ports. A single port that is configured as protected has no effect. Data traffic does not flow between two ports that are protected.
Examples
This example show how to protect CPE port 1 on an LRE port:
Switch# configure terminalSwitch(config)# interface longreachethernet0/1Switch(config-if)# cpe protected port 1Related Commands
Shows CPE protected port information.
Isolates unicast, multicast, and broadcast traffic at Layer 2 from other protected ports on the same switch.
cpe shutdown
Use the cpe shutdown interface configuration command to disable one or more customer premises equipment (CPE) ports. Use the no form of this command to enable a port.
cpe shutdown [port port-id]
no cpe shutdown [port port-id]
This command is available only on Catalyst 2950 Long-Reach Ethernet (LRE) switches.
Syntax Description
port port-id
(Optional) CPE Ethernet port identifier. The range is 1 to 4, depending on the CPE device.
Defaults
The CPE ports are enabled.
Command Modes
Interface configuration
Command History
Usage Guidelines
If the port keyword is not specified, the value is applied globally to all the CPE Ethernet ports. If the port keyword is specified, the value is applied to the specific CPE Ethernet port and overrides any global speed settings.
The CPE Ethernet ports can be shut down at the CPE device level and the port level. If you add a configuration at the CPE device level and at the port level, you must enter the no form of the command for both configurations to return the port to the default state.
Examples
This example shows how to disable all ports on the CPE device:
Switch# configure terminalSwitch(config)# interface longreachethernet0/2Switch(config-if)# cpe shutdownThis example shows how to disable port 2 on the CPE device:
Switch# configure terminalSwitch(config)# interface longreachethernet0/2Switch(config-if)# cpe shutdown port 2After the cpe shutdown port 2 command was entered in the previous example, this example shows how to enable all the CPE Ethernet ports that were not shut down. After the no cpe shutdown command is entered, port 2 is still shut down because the cpe shutdown port 2 command was entered in the previous example. Use the no cpe shutdown port 2 command to enable the port 2.
Switch# configure terminalSwitch(config)# interface longreahethernet0/2Switch(config-if)# no cpe shutdownSwitch(config-if)#Related Commands
show interfaces cpe
Displays CPE Ethernet ports connection, speed, or duplex status.
Disables a port.
cpe speed
Use the cpe speed interface configuration command to set the speed of a customer premises equipment (CPE) port. Use the no form of this command to return to the default setting.
cpe speed {{auto | 10 | 100} [port port-id]}
no cpe speed {{auto | 10 | 100} [port port-id]}
This command is available only on Catalyst 2950 Long-Reach Ethernet (LRE) switches.
Syntax Description
Defaults
The default speed is auto.
Command Modes
Interface configuration
Command History
Usage Guidelines
If you do not enter the port keyword, the speed setting is applied globally to all the CPE Ethernet ports. If you enter the port port-id keywords, the setting is applied to the specified CPE Ethernet port and overrides any global speed settings.
Examples
This example shows how to set a port on a CPE to 100 Mbps:
Switch# configure terminalSwitch(config)# interface longreachethernet0/2Switch(config-if)# cpe speed 100 port 1This example shows how to return the default speed setting on all CPE Ethernet ports that were not configured with the cpe speed {10 | 100} port port-id command:
Switch# configure terminalSwitch(config)# interface longreachethernet0/2Switch(config-if)# no cpe speed 100This example shows how to set port 1 to 10 Mbps, port 2 to 100 Mbps, and the remainder of the ports to autonegotiate.
Switch# configure terminalSwitch(config)# interface longreachethernet0/4Switch(config-if)# cpe speed autoSwitch(config-if)# cpe speed 10 port 1Switch(config-if)# cpe speed 100 port 2This example shows how to set port 1 to autonegotiate after the cpe speed 10 command is entered:
Switch(config-if)# no cpe speed 10 portRelated Commands
Sets the port speed for LRE ports.
show interfaces cpe
Displays connection, speed, and duplex settings for CPE Ethernet ports attached to the specified LRE switch port
cpe toggle
Use the cpe toggle interface configuration command to enable the CPE toggle feature. When this feature is enabled, a remote customer premises equipment (CPE) link automatically transitions from down to up if the Long-Reach Ethernet (LRE) link comes up in less than 30 seconds. Use the no form of this command to disable the CPE toggle feature on a specific port or on the switch.
cpe toggle [port cpe-port-id]
no cpe toggle [port cpe-port-id]
This command is available only on Catalyst 2950 Long-Reach Ethernet (LRE) switches.
Syntax Description
Defaults
CPE toggle is enabled on all interfaces.
Command Modes
Interface configuration
Command History
Usage Guidelines
A CPE Ethernet link is the connection between the CPE Ethernet port and the remote Ethernet device (such as a PC) connected to it. It is not the link between the switch LRE port and the LRE CPE device, which is referred to as the LRE link.
CPE toggle cannot be disabled on a Cisco 575 LRE or Cisco 576 LRE 997 CPE link.
You can disable CPE toggle on a link from a Cisco 585 LRE CPE to a remote Ethernet device. You can disable CPE toggle on all interfaces or on a specific interface by using the no cpe toggle [port cpe-port-id] interface configuration command. If CPE toggle is disabled and the LRE link comes up in less than 30 seconds, the CPE link transitions from down to up.
If the port keyword is not specified, this command applies to all Fast Ethernet ports on a CPE device. If the port keyword and a port ID are specified, this command applies to the specific Fast Ethernet port on the CPE and overrides the global configuration.
Examples
This example shows how to disable CPE toggle on a CPE port:
Switch# configure terminalSwitch(config)# interface longreachethernet0/2Switch(config-if)# no cpe toggleRelated Commands
cpe type
Use the cpe type interface configuration command to set the type of customer premises equipment (CPE) port that is connected to a Long-Reach Ethernet (LRE) switch.
cpe type [cisco575-lre | cisco576-lre997 | cisco585-lre | unknown]
This command is available only on Catalyst 2950 LRE switches.
Syntax Description
Defaults
The default CPE type is unknown.
Command Modes
Interface configuration
Command History
12.1(11)YJ
This command was introduced.
12.1(11)YJ4
The cisco576-lre997 keyword was added.
Usage Guidelines
This command can only be used when the port is shut down. If the link is active on a CPE device port, the switch detects the CPE device type and automatically modifies the configuration. You cannot change the CPE device type on active links. For example, if the active CPE device type is cisco575-lre, you cannot change the type to cisco585-lre or unknown.
Examples
This example shows how to set the CPE device type to cisco585-lre while the link is down:
Switch# configure terminalSwitch(config)# interface longreachethernet0/2Switch(config-if)# cpe type cisco585-lreRelated Commands
show interfaces cpe
Displays connection, speed, and duplex settings for CPE Ethernet ports attached to the specified LRE switch port.
define interface-range
Use the define interface-range global configuration command to create an interface-range macro. Use the no form of this command to delete the defined macro.
define interface-range macro-name interface-range
no define interface-range macro-name interface-range
Syntax Description
macro-name
Name of the interface-range macro; up to 32 characters.
interface-range
Interface range; for valid values for interface ranges, see "Usage Guidelines."
Defaults
This command has no default setting.
Command Modes
Global configuration
Command History
Usage Guidelines
The macro name is a 32-character maximum character string.
A macro can contain up to five ranges.
All interfaces in a range must be the same type; that is, all Fast Ethernet ports, all Gigabit Ethernet ports, all EtherChannel ports, or all VLANs, but you can combine multiple interface types in a macro.
When entering the interface-range, use this format:
•
•
Valid values for type and interface:
•
•
•
•
•
VLAN interfaces must have been configured with the interface vlan command (the show running-config privileged EXEC command displays the configured VLAN interfaces). VLAN interfaces not displayed by the show running-config command cannot be used in interface-ranges.
For physical interfaces, the interface-id is defined as a slot/number (where slot is always 0 for the switch), and the range can be entered as type 0/number - number (for example, fastethernet0/1 - 2). You can also enter multiple ranges.
When you define a range, you must enter a space before and after the hyphen (-):
interface range fastethernet0/1 - 2When you define multiple ranges, you must enter a space before and after the comma (,):
interface range fastethernet0/1 - 2 , gigabitethernet0/1 - 2Examples
This example shows how to create a multiple-interface macro:
Switch(config)# define interface-range macro1 fastethernet0/3 -7 , gigabitethernet0/1Related Commands
delete
Use the delete privileged EXEC command to delete a file or directory on the flash memory device.
delete [/force] [/recursive] filesystem:/file-url
Syntax Description
Command Modes
Privileged EXEC
Command History
12.0(5.2)WC(1)
This command was introduced.
12.1(6)EA2
The /force and /recursive keywords were added.
Usage Guidelines
If you use the /force keyword, you are prompted once at the beginning of the deletion process to confirm the deletion.
If you use the /recursive keyword without the /force keyword, you are prompted to confirm the deletion of every file.
The prompting behavior depends on the setting of the file prompt global configuration command. By default, the switch prompts for confirmation on destructive file operations. For more information about this command, see the Cisco IOS Command Reference for Cisco IOS Release 12.1.
Examples
This example shows how to delete a file from the switch flash memory:
Switch# delete flash:filenameYou can verify that the directory was removed by entering the dir filesystem: privileged EXEC command.
Related Commands
deny (access-list configuration)
Use the deny access-list configuration command to configure conditions for a named or numbered IP access control list (ACL). Use the no form of this command to remove a deny condition from the IP ACL.
Use these commands with standard IP ACLs:
deny {source source-wildcard | host source | any}
no deny {source source-wildcard | host source | any}
Use these commands with extended IP ACLs:
deny protocol {source source-wildcard | host source | any} [operator port] {destination destination-wildcard | host source | any} [operator port] [dscp dscp-value] [time-range time-range-name]
no deny protocol {source source-wildcard | host source | any} [operator port] {destination destination-wildcard | host source | any} [operator port] [dscp dscp-value] [time-range time-range-name]
This command is available on physical interfaces only if your switch is running the enhanced software image (EI).
Syntax Description
Defaults
There are no specific conditions that deny packets in the named or numbered IP ACL.
The default ACL is always terminated by an implicit deny statement for all packets.
Command Modes
Access-list configuration
Command History
Usage Guidelines
Use this command after the ip access-list global configuration command to specify deny conditions for an IP ACL. You can specify a source IP address, destination IP address, IP protocol, TCP port, or UDP port. Specify the TCP and UDP port numbers only if protocol is tcp or udp and operator is eq.
Note
Examples
This example shows how to create an extended IP ACL and to configure deny conditions for it:
Switch(config)# ip access-list extended InternetfilterSwitch(config-ext-nacl)# deny tcp host 190.5.88.10 anySwitch(config-ext-nacl)# deny tcp host 192.1.10.10 anyThis is an example of a standard ACL that sets a deny condition:
Switch(config)# ip access-list standard Acclist1Switch(config-ext-nacl)# deny 192.5.34.0 0.0.0.255Switch(config-ext-nacl)# deny 128.88.10.0 0.0.0.255Switch(config-ext-nacl)# deny 36.1.1.0 0.0.0.255
Note
You can verify your settings by entering the show ip access-lists or the show access-lists privileged EXEC command.
Related Commands
Defines an IP ACL.
Sets conditions for an IP ACL.
Controls access to an interface.
Displays IP ACLs configured on the switch.
Displays ACLs configured on a switch.
deny (MAC access-list configuration)
Use the deny MAC access-list configuration command to prevent Layer 2 traffic from being forwarded if the conditions are matched. Use the no form of this command to remove a deny condition from the MAC named access control list (ACL).
{permit | deny} {any | host src-MAC-addr} {any | host dst-MAC-addr} [aarp | amber | appletalk | dec-spanning | decnet-iv | diagnostic | dsm | etype-6000 | etype-8042 | lat | lavc-sca | mop-console | mop-dump | msdos | mumps | netbios | vines-echo |vines-ip | xns-idp]
no {permit | deny} {any | host src-MAC-addr} {any | host dst-MAC-addr} [aarp | amber | appletalk | dec-spanning | decnet-iv | diagnostic | dsm | etype-6000 | etype-8042 | lat | lavc-sca | mop-console | mop-dump | msdos | mumps | netbios | vines-echo |vines-ip | xns-idp]
This command is available only if your switch is running the enhanced software image (EI).
Syntax Description
Defaults
This command has no defaults. However, the default action for a MAC named ACL is to deny.
Command Modes
MAC access-list configuration
Command History
Usage Guidelines
When an access control entry (ACE) is added to an ACL, an implied deny-any-any condition exists at the end of the list. That is, if there are no matches, the packets are denied. However, before the first ACE is added, the list permits all packets.
These options are not allowed:
•
•
•
Note
Examples
This example shows how to define the MAC named extended ACL to deny NETBIOS traffic from any source to MAC address 00c0.00a0.03fa. Traffic matching this list is denied.
Switch(config-ext-macl)# deny any host 00c0.00a0.03fa netbiosThis example shows how to remove the deny condition from the named MAC extended ACL:
Switch(config-ext-macl)# no deny any host 00c0.00a0.03fa netbiosYou can verify your settings by entering the show access-lists privileged EXEC command.
Related Commands
Creates an ACL based on MAC addresses for non-IP traffic.
Permits Layer 2 traffic to be forwarded if conditions are matched.
Displays ACLs configured on a switch.
dot1x
Use the dot1x global configuration command to enable IEEE 802.1x authentication globally. Use the no form of this command to return to the default setting.
dot1x {system-auth-control} | {guest-vlan supplicant}
no dot1x {system-auth-control} | {guest-vlan supplicant}
Syntax Description
system-auth-control
Enable IEEE 802.1x authentication globally on the switch.
guest-vlan supplicant
Enable optional guest VLAN behavior globally on the switch.
Defaults
IEEE 802.1x authentication is disabled, and the optional guest VLAN behavior is disabled.
Command Modes
Global configuration
Command History
12.1(14)EA1
This command was introduced.
12.1(22)EA2
The guest-vlan supplicant keywords were added.
Usage Guidelines
You must enable authentication, authorization, and accounting (AAA) and specify the authentication method list before enabling IEEE 802.1x authentication globally. A method list describes the sequence and authentication methods to be queried to authenticate a user.
Before globally enabling IEEE 802.1x authentication on a switch, remove the EtherChannel configuration from the interfaces on which IEEE 802.1x authentication and EtherChannel are configured.
If you are using a device running the Cisco Access Control Server (ACS) application for IEEE 802.1x authentication with EAP-Transparent LAN Services (TLS) and with EAP-MD5 and your switch is running Cisco IOS Release 12.1(14)EA1, make sure that the device is running ACS Version 3.2.1 or later.
You can use the guest-vlan supplicant keywords to enable the optional IEEE 802.1x guest VLAN behavior globally on the switch. For more information, see the dot1x guest-vlan command.
Examples
This example shows how to globally enable IEEE 802.1x authentication on a switch:
Switch(config)# dot1x system-auth-controlThis example shows how to globally enable the optional guest VLAN behavior on a switch:
Switch(config)# dot1x guest-vlan supplicantYou can verify your settings by entering the show dot1x privileged EXEC command.
Related Commands
dot1x auth-fail max-attempts
Use the dot1x auth-fail max-attempts interface configuration command to configure the maximum number of authentication attempts allowed before a port is moved to the restricted VLAN. To return to the default setting, use the no form of this command.
dot1x auth-fail max-attempts max-attempts
no dot1x auth-fail max-attempts
Syntax Description
max-attempts
Specify a maximum number of authentication attempts allowed before a port is moved to the restricted VLAN. The range is 1 to 3.
Defaults
The default is 3 attempts.
Command Modes
Interface configuration
Command History
Usage Guidelines
If you reconfigure the maximum number of authentication failures allowed by the VLAN, the change takes effect after the re-authentication timer expires.
Examples
This example shows how to set 2 as the maximum number of authentication attempts allowed before the port is moved to the restricted VLAN on Gigabit Ethernet interface 1:
Switch# configure terminalEnter configuration commands, one per line. End with CNTL/Z.Switch(config)# interface gigabitethernet0/1Switch(config-if)# dot1x auth-fail max-attempts 2Switch(config-if)# endSwitch(config)# endSwitch#You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
dot1x auth-fail vlan [vlan id]
Enables the optional restricted VLAN feature.
show dot1x [interface interface-id]
Displays IEEE 802.1x status for the specified port.
dot1x auth-fail vlan
Use the dot1x auth-fail vlan interface configuration command to enable the restricted VLAN on a port. To return to the default setting, use the no form of this command.
dot1x auth-fail vlan vlan-id
no dot1x auth-fail vlan vlan-id
Syntax Description
Defaults
No restricted VLAN is configured.
Command Modes
Interface configuration
Command History
Usage Guidelines
You can configure a restricted VLAN on ports configured as follows:
•
•
You should enable re-authentication. The ports in restricted VLANs do not receive re-authentication requests if re-authentication is disabled. To start the re-authentication process, the restricted VLAN must receive a link down event or an Extensible Authentication Protocol (EAP) logoff event from the port. If the host is connected through a hub, the port might never receive a link down event and might not detect the new host until the next re-authentication attempt occurs. Therefore, re-authentication should be enabled.
If the user fails authentication, the port is moved to a restricted VLAN, and an EAP success message is sent to the user. Because the user is not notified of the authentication failure, there might be confusion as to why there is restricted access to the network. An EAP success message is sent for these reasons:
•
•
A user might cache an incorrect username and password combination after receiving an EAP success message from the authenticator and re-use that information in every re-authentication. Until the user passes the correct username and password combination, the port remains in the restricted VLAN.
Internal VLANs that are used for Layer 3 ports cannot be configured as a restricted VLAN.
You cannot configure a VLAN to be both a restricted VLAN and a voice VLAN. If you do this, a syslog message appears.
When a restricted VLAN port is moved to an unauthorized state, the authentication process is restarted. If the user fails the authentication process again, the authenticator waits in the held state. After the user has correctly re-authenticated, all IEEE 802.1x ports are reinitialized and treated as normal IEEE 802.1x ports.
When you reconfigure a restricted VLAN to a different VLAN, any ports in the restricted VLAN are also moved, and the ports stay in their current authorized state.
When you shut down or remove a restricted VLAN from the VLAN database, any ports in the restricted VLAN are immediately moved to an unauthorized state, and the authentication process is restarted. The authenticator does not wait in a held state because the restricted VLAN configuration still exists. While the restricted VLAN is inactive, all authentication attempts are counted. As soon as the restricted VLAN becomes active, the port is placed in the restricted VLAN.
The restricted VLAN is supported only in single-host mode (the default port mode).
When a port is placed in a restricted VLAN, the user's MAC address is added to the MAC address table. If a new MAC address appears on the port, it is treated as a security violation.
Examples
This example shows how to configure a restricted VLAN on Gigabit Ethernet interface 1:
Switch# configure terminalEnter configuration commands, one per line. End with CNTL/Z.Switch(config)# interface gigabitethernet0/1Switch(config-if)# dot1x auth-fail vlan 40Switch(config-if)# endSwitch(config)# endSwitch#You can verify your configuration by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
dot1x auth-fail max-attempts [max-attempts]
Configures the number of authentication attempts allowed before assigning a user to the restricted VLAN.
show dot1x [interface interface-id]
Displays IEEE 802.1x status for the specified port.
dot1x control-direction
Use the dot1x control-direction command to change the port to unidirectional or bidirectional control.
dot1x control-direction {in | both}
no dot1x control-direction {in | both}
Syntax Description
dot1x control-direction in
Enable unidirectional control on port.
dot1x control-direction both
Enable bidirectional control on port.
Command Default
The port is set to bidirectional mode.
Command Modes
Interface configuration
Command History
Usage Guidelines
Using the keyword both or using the no form of this command are the same command.
The keyword both and the no form of the command change the port to its bidirectional default setting.
Examples
This example shows how to enable unidirectional control:
Switch(config-if)# dot1x control-direction inThese examples show how to enable bidirectional control:
Switch(config-if)# dot1x control-direction bothSwitch(config-if)# no dot1x control-directionYou can verify your settings by entering the show dot1x all privileged EXEC command.
The show dot1x all privileged EXEC command output is the same for all switches except for the port names and the state of the port. If a host is attached to the port but is not yet authenticated, a display similar to this appears:
Supplicant MAC 0002.b39a.9275AuthSM State = CONNECTINGBendSM State = IDLEPortStatus = UNAUTHORIZEDIf you enter the dot1x control-direction in interface configuration command to enable unidirectional control, this appears in the show dot1x all command output:
ControlDirection = InIf you enter the dot1x control-direction in interface configuration command and the port cannot support this mode due to a configuration conflict, this appears in the show dot1x all command output:
ControlDirection = In (Disabled due to port settings)Related Commands
show dot1x all [interface interface-id]
Displays control-direction port setting status for the specified interface.
dot1x default
Use the dot1x default interface configuration command to reset the configurable IEEE 802.1x parameters to their default values.
dot1x default
Syntax Description
This command has no arguments or keywords.
Defaults
These are the default values:
•
•
•
•
•
•
•
•
•
Command Modes
Interface configuration
Command History
12.1(6)EA2
This command was introduced.
12.1(14)EA1
This command was changed to the interface configuration mode.
Examples
This example shows how to reset the configurable IEEE 802.1x parameters on an interface:
Switch(config-if)# dot1x defaultYou can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
show dot1x [interface interface-id]
Displays IEEE 802.1x status for the specified interface.
dot1x guest-vlan
Use the dot1x guest-vlan interface configuration command to specify an active VLAN as an IEEE 802.1x guest VLAN for switches running the enhanced software image (EI). Use the no form of this command to return to the default setting.
dot1x guest-vlan vlan-id
no dot1x guest-vlan
Syntax Description
Defaults
No guest VLAN is configured.
Command Modes
Interface configuration
Command History
12.1(14)EA1
This command was introduced.
12.1(22)EA2
This command was modified to change the default guest VLAN behavior.
Usage Guidelines
You can configure a guest VLAN for each IEEE 802.1x port on the switch to provide limited services to clients (a device or workstation connected to the switch) not currently running IEEE 802.1x authentication. These users might be upgrading their system for IEEE 802.1x authentication, and some hosts, such as Windows 98 systems, might not be IEEE 802.1x-capable.
When you enable a guest VLAN on an IEEE 802.1x port, the switch assigns clients to a guest VLAN when it does not receive a response to its Extensible Authentication Protocol over LAN (EAPOL) request/identity frame or when EAPOL packets are not sent by the client.
Before Cisco IOS Release 12.1(22)EA2, the switch did not maintain the EAPOL packet history and allowed clients that failed authentication access to the guest VLAN, regardless of whether EAPOL packets had been detected on the interface. You can use the dot1x guest-vlan supplicant global configuration command to enable this behavior.
With Cisco IOS Release 12.1(22)EA2 and later, the switch maintains the EAPOL packet history. If another EAPOL packet is detected on the interface during the lifetime of the link, the guest VLAN feature is disabled. If the port is already in the guest VLAN state, the port is returned to the unauthorized state, and authentication is restarted. The EAPOL history is reset upon loss of link.
Entering the dot1x guest-vlan supplicant global configuration command disables this behavior.
Any number of non-IEEE-802.1x-capable clients are allowed access when the switch port is moved to the guest VLAN. If an IEEE 802.1x-capable client joins the same port on which the guest VLAN is configured, the port is put into the unauthorized state in the user-configured access VLAN, and authentication is restarted.
Guest VLANs are supported on IEEE 802.1x ports in single-host or multiple-hosts mode.
You can configure any active VLAN except an RSPAN VLAN or a voice VLAN as an IEEE 802.1x guest VLAN. The guest VLAN feature is not supported on trunk ports; it is supported only on access ports.
After you configure a guest VLAN for an IEEE 802.1x port to which a DHCP client is connected, you might need to get a host IP address from a DHCP server. You can also change the settings for restarting the IEEE 802.1x authentication process on the switch before the DHCP process on the client times out and tries to get a host IP address from the DHCP server. Decrease the settings for the IEEE 802.1x authentication process (IEEE 802.1x quiet period and switch-to-client transmission time).
Examples
This example shows how to specify VLAN 5 as an IEEE 802.1x guest VLAN:
Switch(config-if)# dot1x guest-vlan 5This example shows how to set 3 as the quiet time on the switch, to set 15 as the number of seconds that the switch waits for a response to an EAP-request/identity frame from the client before resending the request, and to enable VLAN 5 as an IEEE 802.1x guest VLAN when an IEEE 802.1x port is connected to a DHCP client:
Switch(config-if)# dot1x timeout quiet-period 3Switch(config-if)# dot1x timeout tx-period 15Switch(config-if)# dot1x guest-vlan 5This example shows how to enable the optional guest VLAN behavior and to specify VLAN 5 as an IEEE 802.1x guest VLAN:
Switch(config)# dot1x guest-vlan supplicantSwitch(config)# interface FastEthernet0/1Switch(config-if)# dot1x guest-vlan 5You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
Enables the optional guest VLAN supplicant feature.
show dot1x [interface interface-id]
Displays IEEE 802.1x status for the specified interface.
dot1x host-mode
Use the dot1x host-mode interface configuration command to allow a single host (client) or multiple hosts on an IEEE 802.1x-authorized port that has the dot1x port-control interface configuration command set to auto. Use the no form of this command to return to the default setting.
dot1x host-mode {multi-host | single-host}
no dot1x host-mode [multi-host | single-host]
Syntax Description
multi-host
Enable multiple-hosts mode on the switch.
single-host
Enable single-host mode on the switch.
Defaults
The default is single-host mode.
Command Modes
Interface configuration
Command History
12.1(14)EA1
This command was introduced. It replaces the dot1x multiple-hosts interface configuration command.
Usage Guidelines
You can use this command to limit an IEEE 802.1x-enabled port to a single client or to attach multiple clients to an IEEE 802.1x-enabled port. In multiple-hosts mode, only one of the attached hosts must be successfully authorized for all hosts to be granted network access. If the port becomes unauthorized (re-authentication fails, or an Extensible Authentication Protocol over LAN [EAPOL]-logoff message is received), all attached clients are denied access to the network.
Before entering this command, make sure that the dot1x port-control interface configuration command is set to auto for the specified interface.
Examples
This example shows how to enable IEEE 802.1x authentication globally, enable IEEE 802.1x authentication on an interface, and enable multiple-hosts mode:
Switch(config)# dot1x system-auth-controlSwitch(config)# interface fastethernet0/1Switch(config-if)# dot1x port-control autoSwitch(config-if)# dot1x host-mode multi-hostYou can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
show dot1x [interface interface-id]
Displays IEEE 802.1x status for the specified interface.
dot1x initialize
Use the dot1x initialize privileged EXEC command to manually return an IEEE 802.1x-enabled port to an unauthorized state before initiating a new authentication session on the interface.
dot1x initialize interface interface-id
Syntax Description
This command has no arguments or keywords.
Defaults
There is no default setting.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
Use this command to manually return a device connected to a switch interface to an unauthorized state before initiating a new authentication session on the interface.
Examples
This example shows how to manually return a device connected to a port to an unauthorized state:
Switch# dot1x initialize interface fastethernet0/1You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
show dot1x [interface interface-id]
Displays IEEE 802.1x status for the specified interface.
dot1x max-req
Use the dot1x max-req interface configuration command to set the maximum number of times that the switch sends an Extensible Authentication Protocol (EAP) frame from the authentication server (assuming that no response is received) to the client before restarting the authentication process. Use the no form of this command to return to the default setting.
dot1x max-req count
no dot1x max-req
Syntax Description
count
Number of times that the switch sends an EAP frame from the authentication server before restarting the authentication process. The range is 1 to 10.
Defaults
The default is 2.
Command Modes
Interface configuration
Command History
12.1(6)EA2
This command was introduced.
12.1(14)EA1
This command was changed to the interface configuration mode.
Usage Guidelines
You should change the default value of this command only to adjust for unusual circumstances such as unreliable links or specific behavioral problems with certain clients and authentication servers.
Examples
This example shows how to set 5 as the number of times that the switch sends an EAP frame before restarting the authentication process:
Switch(config-if)# dot1x max-req 5You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
Sets the number of seconds that the switch waits for a response to an EAP-request/identity frame from the client before resending the request.
show dot1x [interface interface-id]
Displays IEEE 802.1x status for the specified interface.
dot1x multiple-hosts
This is an obsolete command.
In past releases, the dot1x multiple-hosts interface configuration command was used to allow multiple hosts (clients) on an IEEE 802.1x-authorized port.
Command History
12.1(6)EA2
This command was introduced.
12.1(14)EA1
The dot1x multiple-hosts interface configuration command was replaced by the dot1x host-mode interface configuration command.
Related Commands
Set the IEEE 802.1x host mode on an interface.
Displays IEEE 802.1x statistics, administrative status, and operational status for the switch or for the specified interface.
dot1x port-control
Use the dot1x port-control interface configuration command to enable manual control of the authorization state of the port. Use the no form of this command to return to the default setting.
dot1x port-control {auto | force-authorized | force-unauthorized}
no dot1x port-control
Syntax Description
Defaults
The default is force-authorized.
Command Modes
Interface configuration
Command History
Usage Guidelines
You must enable IEEE 802.1x authentication globally on the switch by using the dot1x system-auth-control global configuration command before enabling IEEE 802.1x authentication on a specific interface.
The IEEE 802.1x protocol is supported on Layer 2 static-access ports.
You can use the auto keyword only if the port is not configured as one of these:
•
•
•
•
•
To disable IEEE 802.1x authentication globally on the switch, use the no dot1x system-auth-control global configuration command. To disable IEEE 802.1x authentication on a specific interface, use the no dot1x port-control interface configuration command.
Examples
This example shows how to enable IEEE 802.1x authentication on an interface:
Switch(config)# interface fastethernet0/1Switch(config-if)# dot1x port-control autoYou can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
show dot1x [interface interface-id]
Displays IEEE 802.1x status for the specified interface.
dot1x re-authenticate
Use the dot1x re-authenticate privileged EXEC command to manually initiate a re-authentication of the IEEE 802.1x-enabled port.
dot1x re-authenticate {interface interface-id}
Syntax Description
Defaults
There is no default setting.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
You can use this command to re-authenticate a client without waiting for the configured number of seconds between re-authentication attempts (re-authperiod) and automatic re-authentication.
Examples
This example shows how to manually re-authenticate the device connected to an interface:
Switch# dot1x re-authenticate interface fastethernet0/1Related Commands
Displays IEEE 802.1x statistics, administrative status, and operational status for the switch or for the specified interface.
dot1x re-authentication
This is an obsolete command.
In past releases, the dot1x re-authentication global configuration command was used to set the amount of time between periodic re-authentication attempts.
Command History
12.1(6)EA2
This command was introduced.
12.1(14)EA1
The dot1x reauthentication interface configuration command replaced the dot1x re-authentication global configuration command.
Related Commands
dot1x reauthentication
Use the dot1x reauthentication interface configuration command to enable periodic re-authentication of the client. Use the no form of this command to return to the default setting.
dot1x reauthentication
no dot1x reauthentication
Syntax Description
This command has no arguments or keywords.
Defaults
Periodic re-authentication is disabled.
Command Modes
Interface configuration
Command History
12.1(14)EA1
This command was introduced. It replaces the dot1x re-authentication global configuration command (with the hyphen).
Usage Guidelines
You configure the amount of time between periodic re-authentication attempts by using the dot1x timeout reauth-period interface configuration command.
Examples
This example shows how to disable periodic re-authentication of the client:
Switch(config-if)# no dot1x reauthenticationThis example shows how to enable periodic re-authentication and to set the number of seconds between re-authentication attempts to 4000 seconds:
Switch(config-if)# dot1x reauthenticationSwitch(config-if)# dot1x timeout reauth-period 4000You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
Sets the number of seconds between re-authentication attempts.
show dot1x [interface interface-id]
Displays IEEE 802.1x status for the specified interface.
dot1x timeout
Use the dot1x timeout interface configuration command to set the IEEE 802.1x timers. Use the no form of this command to return to the default setting.
dot1x timeout {quiet-period seconds | reauth-period {seconds | server} | server-timeout seconds | supp-timeout seconds | tx-period seconds}
no dot1x timeout {quiet-period | reauth-period | server-timeout | supp-timeout | tx-period}
Syntax Description
