Command Reference, Cisco IOS XE Everest 16.6.x (Catalyst 9300 Switches)

channel-group

To assign an Ethernet port to an EtherChannel group, or to enable an EtherChannel mode, or both, use the channel-group command in interface configuration mode. To remove an Ethernet port from an EtherChannel group, use the no form of this command.

channel-group|channel-group-number mode {active | auto [non-silent] | desirable [non-silent] | on | passive}

no channel-group

Syntax Description


`channel-group-number`
mode	Specifies the EtherChannel mode.
active	Unconditionally enables Link Aggregation Control Protocol (LACP).
auto	Enables the Port Aggregation Protocol (PAgP) only if a PAgP device is detected.
non-silent	(Optional) Configures the interface for nonsilent operation when connected to a partner that is PAgP-capable. Use in PAgP mode with the auto or desirable keyword when traffic is expected from the other device.
desirable	Unconditionally enables PAgP.
on	Enables the on mode.
passive	Enables LACP only if a LACP device is detected.

Command Default

No channel groups are assigned.

No mode is configured.

Command Modes

Interface configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

For Layer 2 EtherChannels, the channel-group command automatically creates the port-channel interface when the channel group gets its first physical port. You do not have to use the interface port-channel command in global configuration mode to manually create a port-channel interface. If you create the port-channel interface first, the channel-group-number can be the same as the port-channel-number , or you can use a new number. If you use a new number, the channel-group command dynamically creates a new port channel.

After you configure an EtherChannel, configuration changes that you make on the port-channel interface apply to all the physical ports assigned to the port-channel interface. Configuration changes applied to the physical port affect only the port where you apply the configuration. To change the parameters of all ports in an EtherChannel, apply configuration commands to the port-channel interface, for example, spanning-tree commands or commands to configure a Layer 2 EtherChannel as a trunk.

Active mode places a port into a negotiating state in which the port initiates negotiations with other ports by sending LACP packets. A channel is formed with another port group in either the active or passive mode.

Auto mode places a port into a passive negotiating state in which the port responds to PAgP packets it receives but does not start PAgP packet negotiation. A channel is formed only with another port group in desirable mode. When auto is enabled, silent operation is the default.

Desirable mode places a port into an active negotiating state in which the port starts negotiations with other ports by sending PAgP packets. An EtherChannel is formed with another port group that is in the desirable or auto mode. When desirable is enabled, silent operation is the default.

If you do not specify non-silent with the auto or desirable mode, silent is assumed. The silent mode is used when the device is connected to a device that is not PAgP-capable and rarely, 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 port to a channel group, and to use the port for transmission. Both ends of the link cannot be set to silent.

In on mode, a usable EtherChannel exists only when both connected port groups are in the on mode.

Caution

Use care when using the on mode. This is a manual configuration, and ports on both ends of the EtherChannel must have the same configuration. If the group is misconfigured, packet loss or spanning-tree loops can occur.

Passive mode places a port into a negotiating state in which the port responds to received LACP packets but does not initiate LACP packet negotiation. A channel is formed only with another port group in active mode.

Do not configure an EtherChannel in both the PAgP and LACP modes. EtherChannel groups running PAgP and LACP can coexist on the same device or on different devices in the stack (but not in a cross-stack configuration). Individual EtherChannel groups can run either PAgP or LACP, but they cannot interoperate.

If you set the protocol by using the channel-protocol interface configuration command, the setting is not overridden by the channel-group interface configuration command.

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.

Do not configure a secure port as part of an EtherChannel or configure an EtherChannel port as a secure port.

For a complete list of configuration guidelines, see the “Configuring EtherChannels” chapter in the software configuration guide for this release.

Caution

Do not assign bridge groups on the physical EtherChannel ports because it creates loops.

Examples

This example shows how to configure an EtherChannel on a single device in the stack. It assigns two static-access ports in VLAN 10 to channel 5 with the PAgP mode desirable:

Device# configure terminal
Device(config)# interface range GigabitEthernet 2/0/1 - 2
Device(config-if-range)# switchport mode access
Device(config-if-range)# switchport access vlan 10
Device(config-if-range)# channel-group 5 mode desirable
Device(config-if-range)# end

This example shows how to configure an EtherChannel on a single device in the stack. It assigns two static-access ports in VLAN 10 to channel 5 with the LACP mode active:

Device# configure terminal
Device(config)# interface range GigabitEthernet 2/0/1 - 2
Device(config-if-range)# switchport mode access
Device(config-if-range)# switchport access vlan 10
Device(config-if-range)# channel-group 5 mode active
Device(config-if-range)# end

This example shows how to configure a cross-stack EtherChannel in a device stack. It uses LACP passive mode and assigns two ports on stack member 2 and one port on stack member 3 as static-access ports in VLAN 10 to channel 5:

Device# configure terminal
Device(config)# interface range GigabitEthernet 2/0/4 - 5
Device(config-if-range)# switchport mode access
Device(config-if-range)# switchport access vlan 10
Device(config-if-range)# channel-group 5 mode passive
Device(config-if-range)# exit
Device(config)# interface GigabitEthernet 3/0/3
Device(config-if)# switchport mode access
Device(config-if)# switchport access vlan 10
Device(config-if)# channel-group 5 mode passive
Device(config-if)# exit

You can verify your settings by entering the show running-config privileged EXEC command.

channel-protocol

To restrict the protocol used on a port to manage channeling, use the channel-protocol command in interface configuration mode. To return to the default setting, use the no form of this command.

channel-protocol {lacp | pagp}

no channel-protocol

Syntax Description


lacp	Configures an EtherChannel with the Link Aggregation Control Protocol (LACP).
pagp	Configures an EtherChannel with the Port Aggregation Protocol (PAgP).

Command Default

No protocol is assigned to the EtherChannel.

Command Modes

Interface configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

Use the channel-protocol command only to restrict a channel to LACP or PAgP. If you set the protocol by using the channel-protocol command, the setting is not overridden by the channel-group interface configuration command.

You must use the channel-group interface configuration command to configure the EtherChannel parameters. The channel-group command also can set the mode for the EtherChannel.

You cannot enable both the PAgP and LACP modes on an EtherChannel group.

PAgP and LACP are not compatible; both ends of a channel must use the same protocol.

You cannot configure PAgP on cross-stack configurations.

Examples

This example shows how to specify LACP as the protocol that manages the EtherChannel:

Device(config-if)# channel-protocol lacp

You can verify your settings by entering the show etherchannel [channel-group-number] protocol privileged EXEC command.

clear lacp

To clear Link Aggregation Control Protocol (LACP) channel-group counters, use the clear lacp command in privileged EXEC mode.

clear lacp [channel-group-number] counters

Syntax Description


`channel-group-number`
counters	Clears traffic counters.

Command Default

None

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

You can clear all counters by using the clear lacp counters command, or you can clear only the counters for the specified channel group by using the clear lacp channel-group-number counters command.

Examples

This example shows how to clear all channel-group information:

Device# clear lacp counters

This example shows how to clear LACP traffic counters for group 4:

Device# clear lacp 4 counters

You can verify that the information was deleted by entering the show lacp counters or the show lacp channel-group-number counters privileged EXEC command.

clear pagp

To clear the Port Aggregation Protocol (PAgP) channel-group information, use the clear pagp command in privileged EXEC mode.

clear pagp [channel-group-number] counters

Syntax Description


`channel-group-number`
counters	Clears traffic counters.

Command Default

None

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

You can clear all counters by using the clear pagp counters command, or you can clear only the counters for the specified channel group by using the clear pagp channel-group-number counters command.

Examples

This example shows how to clear all channel-group information:

Device# clear pagp counters

This example shows how to clear PAgP traffic counters for group 10:

Device# clear pagp 10 counters

You can verify that the information was deleted by entering the show pagp privileged EXEC command.

clear spanning-tree counters

To clear the spanning-tree counters, use the clear spanning-tree counters command in privileged EXEC mode.

clear spanning-tree counters [ interface interface-id]

Syntax Description


interface `interface-id`	(Optional) Clears all spanning-tree counters on the specified interface. Valid interfaces include physical ports, VLANs, and port channels. The VLAN range is 1 to 4094. The port-channel range is 1 to 128.

Command Default

None

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

If the interface-id value is not specified, spanning-tree counters are cleared for all interfaces.

Examples

This example shows how to clear spanning-tree counters for all interfaces:


Device# clear spanning-tree counters

clear spanning-tree detected-protocols

To restart the protocol migration process and force renegotiation with neighboring devices on the interface, use the clear spanning-tree detected-protocols command in privileged EXEC mode.

clear spanning-tree detected-protocols [interface interface-id]

Syntax Description


interface `interface-id`	(Optional) Restarts the protocol migration process on the specified interface. Valid interfaces include physical ports, VLANs, and port channels. The VLAN range is 1 to 4094.

Command Default

None

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

A device running the rapid per-VLAN spanning-tree plus (rapid-PVST+) protocol or the Multiple Spanning Tree Protocol (MSTP) supports a built-in protocol migration method that enables it to interoperate with legacy IEEE 802.1D devices. If a rapid-PVST+ or an MSTP device receives a legacy IEEE 802.1D configuration bridge protocol data unit (BPDU) with the protocol version set to 0, the device sends only IEEE 802.1D BPDUs on that port. A multiple spanning-tree (MST) device 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 a rapid spanning-tree (RST) BPDU (Version 2).

The device does not automatically revert to the rapid-PVST+ or the MSTP mode if it no longer receives IEEE 802.1D BPDUs because it cannot learn 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 a port:


Device# clear spanning-tree detected-protocols interface gigabitethernet2/0/1

debug etherchannel

To enable debugging of EtherChannels, use the debug etherchannel command in privileged EXEC mode. To disable debugging, use the no form of the command.

debug etherchannel [all | detail | error | event | idb ]

no debug etherchannel [all | detail | error | event | idb ]

Syntax Description


all	(Optional) Displays all EtherChannel debug messages.
detail	(Optional) Displays detailed EtherChannel debug messages.
error	(Optional) Displays EtherChannel error debug messages.
event	(Optional) Displays EtherChannel event messages.
idb	(Optional) Displays PAgP interface descriptor block debug messages.

Command Default

Debugging is disabled.

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

The undebug etherchannel command is the same as the no debug etherchannel command.

Note

Although the linecard keyword is displayed in the command-line help, it is not supported.

When you enable debugging on a stack, it is enabled only on the active switch. To enable debugging on the standby switch , start a session from the active switch by using the session switch-number command in privileged EXEC mode. Enter the debug command at the command-line prompt of the standby switch.

To enable debugging on the standby switch without first starting a session on the active switch, use the remote command switch-number LINE command in privileged EXEC mode.

Examples

This example shows how to display all EtherChannel debug messages:

Device# debug etherchannel all

This example shows how to display debug messages related to EtherChannel events:

Device# debug etherchannel event

debug lacp

To enable debugging of Link Aggregation Control Protocol (LACP) activity, use the debug lacp command in privileged EXEC mode. To disable LACP debugging, use the no form of this command.

debug lacp [all | event | fsm | misc | packet]

no debug lacp [all | event | fsm | misc | packet]

Syntax Description


all	(Optional) Displays all LACP debug messages.
event	(Optional) Displays LACP event debug messages.
fsm	(Optional) Displays messages about changes within the LACP finite state machine.
misc	(Optional) Displays miscellaneous LACP debug messages.
packet	(Optional) Displays the receiving and transmitting LACP control packets.

Command Default

Debugging is disabled.

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

The undebug etherchannel command is the same as the no debug etherchannel command.

When you enable debugging on a stack, it is enabled only on the active switch. To enable debugging on the standby switch , start a session from the active switch by using the session switch-number command in privileged EXEC mode. Enter the debug command at the command-line prompt of the standby switch.

To enable debugging on the standby switch without first starting a session on the active switch, use the remote command switch-number LINE command in privileged EXEC mode.

Examples

This example shows how to display all LACP debug messages:

Device# debug LACP all

This example shows how to display debug messages related to LACP events:

Device# debug LACP event

debug pagp

To enable debugging of Port Aggregation Protocol (PAgP) activity, use the debug pagp command in privileged EXEC mode. To disable PAgP debugging, use the no form of this command.

Syntax Description


all	(Optional) Displays all PAgP debug messages.
dual-active	(Optional) Displays dual-active detection messages.
event	(Optional) Displays PAgP event debug messages.
fsm	(Optional) Displays messages about changes within the PAgP finite state machine.
misc	(Optional) Displays miscellaneous PAgP debug messages.
packet	(Optional) Displays the receiving and transmitting PAgP control packets.

Command Default

Debugging is disabled.

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

The undebug pagp command is the same as the no debug pagp command.

When you enable debugging on a stack, it is enabled only on the active switch. To enable debugging on the standby switch , start a session from the active switch by using the session switch-number command in privileged EXEC mode. Enter the debug command at the command-line prompt of the standby switch.

To enable debugging on the standby switch without first starting a session on the active switch, use the remote command switch-number LINE command in privileged EXEC mode.

Examples

This example shows how to display all PAgP debug messages:

Device# debug pagp all

This example shows how to display debug messages related to PAgP events:

Device# debug pagp event

debug platform pm

To enable debugging of the platform-dependent port manager software module, use the debug platform pm command in privileged EXEC mode. To disable debugging, use the no form of this command.

Syntax Description


all	Displays all port manager debug messages.
counters	Displays counters for remote procedure call (RPC) debug messages.
errdisable	Displays error-disabled-related events debug messages.
if-numbers	Displays interface-number translation event debug messages.
link-status	Displays interface link-detection event debug messages.
platform	Displays port manager function event debug messages.
pm-vectors	Displays port manager vector-related event debug messages.
detail	(Optional) Displays vector-function details.
vlans	Displays VLAN creation and deletion event debug messages.

Command Default

Debugging is disabled.

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

The undebug platform pm command is the same as the no debug platform pm command.

When you enable debugging on a stack, it is enabled only on the active switch. To enable debugging on the standby switch , start a session from the active switch by using the session switch-number command in privileged EXEC mode. Enter the debug command at the command-line prompt of the standby switch.

To enable debugging on the standby switch without first starting a session on the active switch, use the remote command switch-number LINE command in privileged EXEC mode.

Examples

This example shows how to display debug messages related to the creation and deletion of VLANs:

Device# debug platform pm vlans

debug platform udld

To enable debugging of the platform-dependent UniDirectional Link Detection (UDLD) software, use the debug platform udld command in privileged EXEC mode. To disable debugging, use the no form of this command.

Syntax Description


error	(Optional) Displays error condition debug messages.

Command Default

Debugging is disabled.

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

The undebug platform udld command is the same as the no debug platform udld command.

debug spanning-tree

To enable debugging of spanning-tree activities, use the debug spanning-tree command in EXEC mode. To disable debugging, use the no form of this command.

debug spanning-tree {all | backbonefast | bpdu | bpdu-opt | config | etherchannel | events | exceptions | general | ha | mstp | pvst+ | root | snmp | synchronization | switch | uplinkfast}

no debug spanning-tree {all | backbonefast | bpdu | bpdu-opt | config | etherchannel | events | exceptions | general | mstp | pvst+ | root | snmp | synchronization | switch | uplinkfast}

Syntax Description


all	Displays all spanning-tree debug messages.
backbonefast	Displays BackboneFast-event debug messages.
bpdu	Displays spanning-tree bridge protocol data unit (BPDU) debug messages.
bpdu-opt	Displays optimized BPDU handling debug messages.
config	Displays spanning-tree configuration change debug messages.
etherchannel	Displays EtherChannel-support debug messages.
events	Displays spanning-tree topology event debug messages.
exceptions	Displays spanning-tree exception debug messages.
general	Displays general spanning-tree activity debug messages.
ha	Displays high-availability spanning-tree debug messages.
mstp	Debugs Multiple Spanning Tree Protocol (MSTP) events.
pvst+	Displays per-VLAN spanning-tree plus (PVST+) event debug messages.
root	Displays spanning-tree root-event debug messages.
snmp	Displays spanning-tree Simple Network Management Protocol (SNMP) handling debug messages.
switch	Displays device shim command debug messages. This shim is the software module that is the interface between the generic Spanning Tree Protocol (STP) code and the platform-specific code of various device platforms.
synchronization	Displays the spanning-tree synchronization event debug messages.
uplinkfast	Displays UplinkFast-event debug messages.

Command Default

Debugging is disabled.

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

The undebug spanning-tree command is the same as the no debug spanning-tree command.

When you enable debugging on a stack, it is enabled only on the active switch. To enable debugging on the standby switch , start a session from the active switch by using the session switch-number command in privileged EXEC mode. Enter the debug command at the command-line prompt of the standby switch.

To enable debugging on the standby switch without first starting a session on the active switch, use the remote command switch-number LINE command in privileged EXEC mode.

Examples

This example shows how to display all spanning-tree debug messages:

Device# debug spanning-tree all

interface port-channel

To access or create a port channel, use the interface port-channel command in global configuration mode. Use the no form of this command to remove the port channel.

interface port-channel port-channel-number

no interface port-channel

Syntax Description


`port-channel-number`

Command Default

No port channel logical interfaces are defined.

Command Modes

Global configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

For Layer 2 EtherChannels, you do not have to create a port-channel interface before assigning physical ports to a channel group. Instead, you can use the channel-group interface configuration command, which automatically creates the port-channel interface when the channel group obtains its first physical port. If you create the port-channel interface first, the channel-group-number can be the same as the port-channel-number , or you can use a new number. If you use a new number, the channel-group command dynamically creates a new port channel.

Only one port channel in a channel group is allowed.

Follow these guidelines when you use the interface port-channel command:

If you want to use the Cisco Discovery Protocol (CDP), you must configure it on the physical port and not on the port channel interface.
Do not configure a port that is an active member of an EtherChannel as an IEEE 802.1x port. If IEEE 802.1x is enabled on a not-yet active port of an EtherChannel, the port does not join the EtherChannel.

For a complete list of configuration guidelines, see the “Configuring EtherChannels” chapter in the software configuration guide for this release.

Examples

This example shows how to create a port channel interface with a port channel number of 5:

Device(config)# interface port-channel 5

You can verify your setting by entering the show running-config privileged EXEC or show etherchannel channel-group-number detail privileged EXEC command.

lacp max-bundle

To define the maximum number of active LACP ports allowed in a port channel, use the lacp max-bundle command in interface configuration mode. To return to the default setting, use the no form of this command.

lacp max-bundle max_bundle_number

no lacp max-bundle

Syntax Description


`max_bundle_number`	The maximum number of active LACP ports in the port channel. The range is 1 to 8. The default is 8.

Command Default

None

Command Modes

Interface configuration

Command History


Release	Modification
	This command was introduced.

Usage Guidelines

An LACP channel group can have up to 16 Ethernet ports of the same type. Up to eight ports can be active, and up to eight ports can be in hot-standby mode. When there are more than eight ports in an LACP channel group, the device on the controlling end of the link uses port priorities to determine which ports are bundled into the channel and which ports are put in hot-standby mode. Port priorities on the other device (the noncontrolling end of the link) are ignored.

The lacp max-bundle command must specify a number greater than the number specified by the port-channel min-links command.

Use the show etherchannel summary privileged EXEC command to see which ports are in the hot-standby mode (denoted with an H port-state flag in the output display).

Examples

This example shows how to specify a maximum of five active LACP ports in port channel 2:

Device(config)# interface port-channel 2 
Device(config-if)# lacp max-bundle 5

lacp port-priority

To configure the port priority for the Link Aggregation Control Protocol (LACP), use the lacp port-priority command in interface configuration mode. To return to the default setting, use the no form of this command.

lacp port-priority priority

no lacp port-priority

Syntax Description


`priority`	Port priority for LACP. The range is 1 to 65535.

Command Default

The default is 32768.

Command Modes

Interface configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

The lacp port-priority interface configuration command determines which ports are bundled and which ports are put in hot-standby mode when there are more than eight ports in an LACP channel group.

An LACP channel group can have up to 16 Ethernet ports of the same type. Up to eight ports can be active, and up to eight ports can be in standby mode.

In port-priority comparisons, a numerically lower value has a higher priority: When there are more than eight ports in an LACP channel group, the eight ports with the numerically lowest values (highest priority values) for LACP port priority are bundled into the channel group, and the lower-priority ports are put in hot-standby mode. If two or more ports have the same LACP port priority (for example, they are configured with the default setting of 65535), then an internal value for the port number determines the priority.

Note

The LACP port priorities are only effective if the ports are on the device that controls the LACP link. See the lacp system-priority global configuration command for determining which device controls the link.

Use the show lacp internal privileged EXEC command to display LACP port priorities and internal port number values.

For information about configuring LACP on physical ports, see the configuration guide for this release.

Examples

This example shows how to configure the LACP port priority on a port:

Device# interface gigabitethernet2/0/1
Device(config-if)# lacp port-priority 1000

You can verify your settings by entering the show lacp [channel-group-number] internal privileged EXEC command.

lacp rate

To set the rate at which Link Aggregation Control Protocol (LACP) control packets are ingressed to an LACP-supported interface, use the lacp rate command in interface configuration mode. To return to the default settings, use the no form of this command

lacp rate {normal | fast}

no lacp rate

Syntax Description


normal	Specifies that LACP control packets are ingressed at the normal rate, every 30 seconds after the link is bundled.
fast	Specifies that LACP control packets are ingressed at the fast rate, once every 1 second.

Command Default

The default ingress rate for control packets is 30 seconds after the link is bundled.

Command Modes

Interface configuration (config-if)

Command History


Release	Modification
	This command was introduced.

Usage Guidelines

Use this command to modify the duration of LACP timeout. The LACP timeout value on Cisco switch is three times the LACP rate configured on the interface. Using the lacp ratecommand, you can select the LACP timeout value for a switch to be either 90 seconds or 3 seconds.

This command is supported only on LACP-enabled interfaces.

Examples

This example shows how to specify the fast (1 second) ingress rate on interface GigabitEthernet 0/0:

Device(config)# interface gigabitEthernet 0/0 
Device(config-if)# lacp rate fast

lacp system-priority

To configure the system priority for the Link Aggregation Control Protocol (LACP), use the lacp system-priority command in global configuration mode on the device. To return to the default setting, use the no form of this command.

lacp system-priority priority

no lacp system-priority

Syntax Description


`priority`	System priority for LACP. The range is 1 to 65535.

Command Default

The default is 32768.

Command Modes

Global configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

The lacp system-priority command determines which device in an LACP link controls port priorities.

An LACP channel group can have up to 16 Ethernet ports of the same type. Up to eight ports can be active, and up to eight ports can be in standby mode. When there are more than eight ports in an LACP channel group, the device on the controlling end of the link uses port priorities to determine which ports are bundled into the channel and which ports are put in hot-standby mode. Port priorities on the other device (the noncontrolling end of the link) are ignored.

In priority comparisons, numerically lower values have a higher priority. Therefore, the system with the numerically lower value (higher priority value) for LACP system priority becomes the controlling system. If both devices have the same LACP system priority (for example, they are both configured with the default setting of 32768), the LACP system ID (the device MAC address) determines which device is in control.

The lacp system-priority command applies to all LACP EtherChannels on the device.

Use the show etherchannel summary privileged EXEC command to see which ports are in the hot-standby mode (denoted with an H port-state flag in the output display).

Examples

This example shows how to set the LACP system priority:

Device(config)# lacp system-priority 20000

You can verify your settings by entering the show lacp sys-id privileged EXEC command.

pagp learn-method

To learn the source address of incoming packets received from an EtherChannel port, use the pagp learn-method command in interface configuration mode. To return to the default setting, use the no form of this command.

pagp learn-method {aggregation-port | physical-port}

no pagp learn-method

Syntax Description


aggregation-port	Specifies address learning on the logical port channel. The device sends packets to the source using any port in the EtherChannel. This setting is the default. With aggregation-port learning, it is not important on which physical port the packet arrives.
physical-port	Specifies address learning on the physical port within the EtherChannel. The device sends packets to the source using the same port in the EtherChannel from which it learned the source address. The other end of the channel uses the same port in the channel for a particular destination MAC or IP address.

Command Default

The default is aggregation-port (logical port channel).

Command Modes

Interface configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

The learn method must be configured the same at both ends of the link.

The device supports address learning only on aggregate ports even though the physical-port keyword is provided in the command-line interface (CLI). The pagp learn-method and the pagp port-priority interface configuration commands have no effect on the device hardware, but they are required for PAgP interoperability with devices that only support address learning by physical ports.

When the link partner to the device is a physical learner, we recommend that you configure the device as a physical-port learner by using the pagp learn-method physical-port interface configuration command. We also recommend that you set the load-distribution method based on the source MAC address by using the port-channel load-balance src-mac global configuration command. Use the pagp learn-method interface configuration command only in this situation.

Examples

This example shows how to set the learning method to learn the address on the physical port within the EtherChannel:

Device(config-if)# pagp learn-method physical-port

This example shows how to set the learning method to learn the address on the port channel within the EtherChannel:

Device(config-if)# pagp learn-method aggregation-port

You can verify your settings by entering the show running-config privileged EXEC command or the show pagp channel-group-number internal privileged EXEC command.

pagp port-priority

To select a port over which all Port Aggregation Protocol (PAgP) traffic through the EtherChannel is sent, use the pagp port-priority command in interface configuration mode. If all unused ports in the EtherChannel are in hot-standby mode, they can be placed into operation if the currently selected port and link fails. To return to the default setting, use the no form of this command.

pagp port-priority priority

no pagp port-priority

Syntax Description


`priority`	Priority number. The range is from 0 to 255.

Command Default

The default is 128.

Command Modes

Interface configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

The physical port with the highest priority that is operational and has membership in the same EtherChannel is the one selected for PAgP transmission.

The device supports address learning only on aggregate ports even though the physical-port keyword is provided in the command-line interface (CLI). The pagp learn-method and the pagp port-priority interface configuration commands have no effect on the device hardware, but they are required for PAgP interoperability with devices that only support address learning by physical ports, such as the Catalyst 1900 switch.

When the link partner to the device is a physical learner, we recommend that you configure the device as a physical-port learner by using the pagp learn-method physical-port interface configuration command. We also recommend that you set the load-distribution method based on the source MAC address by using the port-channel load-balance src-mac global configuration command. Use the pagp learn-method interface configuration command only in this situation.

Examples

This example shows how to set the port priority to 200:

Device(config-if)# pagp port-priority 200

You can verify your setting by entering the show running-config privileged EXEC command or the show pagp channel-group-number internal privileged EXEC command.

port-channel

To convert the auto created EtherChannel into a manual channel and adding configuration on the EtherChannel, use the port-channel command in privileged EXEC mode.

port-channel { channel-group-number persistent|persistent }

Syntax Description


`channel-group-number`	Channel group number. The range is 1 to 128.
persistent	Converts the auto created EtherChannel into a manual channel and allows you to add configuration on the EtherChannel.

Command Default

None

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

You can use the show etherchannel summary privileged EXEC command to display the EtherChannel information.

Examples

This example shows how to convert the auto created EtherChannel into a manual channel:

Device# port-channel 1 persistent

port-channel auto

To enable the auto-LAG feature on a switch globally, use the port-channel auto command in global configuration mode. To disable the auto-LAG feature on the switch globally, use no form of this command.

port-channel auto

no port-channel auto

Syntax Description

This command has no arguments or keywords.

Command Default

By default, the auto-LAG feature is disabled globally and is enabled on all port interfaces.

Command Modes

Global configuration

Command History


Release	Modification
Cisco IOS XE 3.7.2E	This command was introduced.

Usage Guidelines

You can use the show etherchannel auto privileged EXEC command to verify if the EtherChannel was created automatically.

Examples

This example shows how to enable the auto-LAG feature on the switch:

Device(config)# port-channel auto

port-channel load-balance

To set the load-distribution method among the ports in the EtherChannel, use the port-channel load-balance command in global configuration mode. To reset the load-balancing mechanism to the default setting, use the no form of this command.

port-channel load-balance {dst-ip | dst-mac | dst-mixed-ip-port | dst-port | extended | src-dst-ip | src-dst-mac | src-dst-mixed-ip-port | src-dst-port | src-ip | src-mac | src-mixed-ip-port | src-port}

no port-channel load-balance

Syntax Description


dst-ip	Specifies load distribution based on the destination host IP address.
dst-mac	Specifies load distribution based on the destination host MAC address. Packets to the same destination are sent on the same port, but packets to different destinations are sent on different ports in the channel.
dst-mixed-ip-port	Specifies load distribution based on the destination IPv4 or IPv6 address and the TCP/UDP (Layer 4) port number.
dst-port	Specifies load distribution based on the destination TCP/UDP (Layer 4) port number for both IPv4 and IPv6.
extended	Sets extended load balance methods among the ports in the EtherChannel. See the port-channel load-balance extended command.
src-dst-ip	Specifies load distribution based on the source and destination host IP address.
src-dst-mac	Specifies load distribution based on the source and destination host MAC address.
src-dst-mixed-ip-port	Specifies load distribution based on the source and destination host IP address and TCP/UDP (layer 4) port number.
src-dst-port	Specifies load distribution based on the source and destination TCP/UDP (Layer 4) port number.
src-ip	Specifies load distribution based on the source host IP address.
src-mac	Specifies load distribution based on the source MAC address. Packets from different hosts use different ports in the channel, but packets from the same host use the same port.
src-mixed-ip-port	Specifies load distribution based on the source host IP address and TCP/UDP (Layer 4) port number.
src-port	Specifies load distribution based on the TCP/UDP (Layer 4) port number.

Command Default

The default is src-mac.

Command Modes

Global configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

You can verify your setting by entering the show running-config privileged EXEC command or the show etherchannel load-balance privileged EXEC command.

Examples

This example shows how to set the load-distribution method to dst-mac:

Device(config)# port-channel load-balance dst-mac

port-channel load-balance extended

To set combinations of load-distribution methods among the ports in the EtherChannel, use the port-channel load-balance extended command in global configuration mode. To reset the extended load-balancing mechanism to the default setting, use the no form of this command.

no port-channel load-balance extended

Syntax Description


dst-ip	(Optional) Specifies load distribution based on the destination host IP address.
dst-mac	(Optional) Specifies load distribution based on the destination host MAC address. Packets to the same destination are sent on the same port, but packets to different destinations are sent on different ports in the channel.
dst-port	(Optional) Specifies load distribution based on the destination TCP/UDP (Layer 4) port number for both IPv4 and IPv6.
ipv6-label	(Optional) Specifies load distribution based on the source MAC address and IPv6 flow label.
l3-proto	(Optional) Specifies load distribution based on the source MAC address and Layer 3 protocols.
src-ip	(Optional) Specifies load distribution based on the source host IP address.
src-mac	(Optional) Specifies load distribution based on the source MAC address. Packets from different hosts use different ports in the channel, but packets from the same host use the same port.
src-port	(Optional) Specifies load distribution based on the TCP/UDP (Layer 4) port number.

Command Default

The default is src-mac.

Command Modes

Global configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

For information about when to use these forwarding methods, see the for this release.

You can verify your setting by entering the show running-config privileged EXEC command or the show etherchannel load-balance privileged EXEC command.

Examples

This example shows how to set the extended load-distribution method:

Device(config)# port-channel load-balance extended dst-ip dst-mac src-ip

port-channel min-links

To define the minimum number of LACP ports that must be bundled in the link-up state and bundled in the EtherChannel in order that a port channel becomes active, use the port-channel min-links command in interface configuration mode. To return to the default setting, use the no form of this command.

port-channel min-links min_links_number

no port-channel min-links

Syntax Description


`min_links_number`	The minimum number of active LACP ports in the port channel. The range is 2 to 8. The default is 1.

Command Default

None

Command Modes

Interface configuration

Command History


Release	Modification
	This command was introduced.

Usage Guidelines

An LACP channel group can have up to 16 Ethernet ports of the same type. Up to eight ports can be active, and up to eight ports can be in hot-standby mode. When there are more than eight ports in an LACP channel group, the device on the controlling end of the link uses port priorities to determine which ports are bundled into the channel and which ports are put in hot-standby mode. Port priorities on the other device (the noncontrolling end of the link) are ignored.

The port-channel min-links command must specify a number a less than the number specified by the lacp max-bundle command.

Use the show etherchannel summary privileged EXEC command to see which ports are in the hot-standby mode (denoted with an H port-state flag in the output display).

Examples

This example shows how to specify a minimum of three active LACP ports before port channel 2 becomes active:

Device(config)# interface port-channel 2 
Device(config-if)# port-channel min-links 3

rep admin vlan

To configure a Resilient Ethernet Protocol (REP) administrative VLAN for REP to transmit hardware flood layer (HFL) messages, use the rep admin vlan command in global configuration mode. To return to the default configuration with VLAN 1 as the administrative VLAN, use the no form of this command.

rep admin vlan vlan-id

no rep admin vlan

Syntax Description


`vlan-id`	The 48-bit static MAC address.

Command Default

The default value of the administrative VLAN is VLAN 1.

Command Modes

Global configuration (config)

Command History


Release	Modification
	This command was introduced

Usage Guidelines

The range of the REP administrative VLAN is from 2 to 4094.

If you do not configure an administrative VLAN, the default VLAN is VLAN 1. The default VLAN 1 is always configured. There can be only one administrative VLAN on a router and on a segment.

You can verify your settings by entering the show interfaces rep detail privileged EXEC command.

Examples

The following example shows how to configure VLAN 100 as the REP administrative VLAN:

Device(config)#  rep admin vlan 100

rep block port

To configure a REP VLAN load balancing on the REP primary edge port, use the rep block port command in interface configuration mode. To return to the default configuration with VLAN 1 as the administrative VLAN, use the no form of this command.

rep block port { id port-id | neighbor-offset | preferred} vlan { vlan-list | all}

no rep block port { id port-id | neighbor-offset | preferred}

Syntax Description


id `port-id`	Specifies the VLAN blocking alternate port by entering the unique port ID, which is automatically generated when REP is enabled. The REP port ID is a 16-character hexadecimal value. You can display the port ID for an interface by entering the show interface `interface-id` rep detail command in privileged EXEC mode.
`neighbor-offset`	Identifies the VLAN blocking alternate port by entering the offset number of a neighbor. The range is from -256 to +256; a value of 0 is invalid.
preferred	Selects the regular segment port previously identified as the preferred alternate port for VLAN load balancing.
vlan	Identifies the VLANs to be blocked.
`vlan-list`	VLAN ID or range of VLAN IDs to be displayed. Enter a VLAN ID from 1 to 4094 or a range or sequence of VLANs (such as 1-3, 22, 41-44) to be blocked.
all	Blocks all the VLANs.

Command Default

The default behavior after you enter the rep preempt segment command in privileged EXEC (for manual preemption) is to block all VLANs at the primary edge port. This behavior remains until you configure the rep block port command.

If the primary edge port cannot determine which port is to be the alternate port, the default action is no preemption and no VLAN load balancing.

Command Modes

Interface configuration (config-if)

Command History


Release	Modification
	This command was introduced

Usage Guidelines

You must enter this command on the REP primary edge port.

When you select an alternate port by entering an offset number, this number identifies the downstream neighbor port of an edge port. The primary edge port has an offset number of 1; positive numbers above 1 identify downstream neighbors of the primary edge port. Negative numbers identify the secondary edge port (offset number -1) and its downstream neighbors. Do not enter an offset value of 1 because that is the offset number of the primary edge port itself.

If you have configured a preempt delay time by entering the rep preempt delay seconds command in interface configuration mode and a link failure and recovery occurs, VLAN load balancing begins after the configured preemption time period elapses without another link failure. The alternate port specified in the load-balancing configuration blocks the configured VLANs and unblocks all other segment ports. If the primary edge port cannot determine the alternate port for VLAN balancing, the default action is no preemption.

Each port in a segment has a unique port ID. To determine the port ID of a port, enter the show interfaces interface-id rep detail command in privileged EXEC mode.

Examples

The following example shows how to configure REP VLAN load balancing.

Device(config)#  interface TenGigabitEthernet 4/1
Device(config-if)#  rep block port id 0009001818D68700 vlan 1-100

rep lsl-age-timer

To configure the REP link status layer (LSL) age-out timer value, use the rep lsl-age-timer command in interface configuration mode. To restore the default age-out timer value, use the no form of this command.

rep lsl-age-timer milliseconds

no rep lsl-age-timer milliseconds

Syntax Description


`milliseconds`	REP LSL age-out timer value in milliseconds (ms). The range is from 120 ms to 10000 ms in multiples of 40 ms.

Command Default

The default LSL age-out timer value is 5 ms.

Command Modes

Interface configuration (config-if)

Command History


Release	Modification
	This command was introduced

Usage Guidelines

The rep lsl-age-timer command is used to configure the REP LSL age-out timer value. While configuring REP configurable timers, we recommend that you configure the REP LSL number of retries first and then configure the REP LSL age-out timer value.

Examples

The following example shows how to configure REP LSL age-out timer value.

Device(config)#  interface TenGigabitEthernet 4/1
Device(config-if)#  rep segment 1 edge primary
Device(config-if)#  rep lsl-age-timer 2000

rep lsl-retries

To configure the REP link status layer (LSL) number of retries, use the rep lsl-retries command in interface configuration mode. To restore the default number of retries, use the no form of this command.

rep lsl-retries number-of-retries

no rep lsl-retries number-of-retries

Syntax Description


`number-of-retries`	Number of LSL retries. The range of retries is from 3 to 10.

Command Default

The default number of LSL retries is 5.

Command Modes

Interface configuration (config-if)

Command History


Release	Modification
	This command was introduced

Usage Guidelines

The rep lsl-retries command is used to configure the number of retries before the REP link is disabled. While configuring REP configurable timers, we recommend that you configure the REP LSL number of retries first and then configure the REP LSL age-out timer value.

Examples

The following example shows how to configure REP LSL retries.

Device(config)#  interface TenGigabitEthernet 4/1
Device(config-if)#  rep segment 2 edge primary

rep preempt delay

To configure a waiting period after a segment port failure and recovery before REP VLAN load balancing is triggered, use the rep preempt delay command in interface configuration mode. To remove the configured delay, use the no form of this command.

rep preempt delay seconds

no rep preempt delay

Syntax Description


`seconds`	Number of seconds to delay REP preemption. The range is from 15 to 300 seconds. The default is manual preemption without delay.

Command Default

REP preemption delay is not set. The default is manual preemption without delay.

Command Modes

Interface configuration (config-if)

Command History


Release	Modification
	This command was introduced

Usage Guidelines

You must enter this command on the REP primary edge port.

You must enter this command and configure a preempt time delay if you want VLAN load balancing to automatically trigger after a link failure and recovery.

If VLAN load balancing is configured, after a segment port failure and recovery, the REP primary edge port starts a delay timer before VLAN load balancing occurs. Note that the timer restarts after each link failure. When the timer expires, the REP primary edge alerts the alternate port to perform VLAN load balancing (configured by using the rep block port interface configuration command) and prepares the segment for the new topology. The configured VLAN list is blocked at the alternate port, and all other VLANs are blocked at the primary edge port.

You can verify your settings by entering the show interfaces rep privileged EXEC command.

Examples

The following example shows how to configure a REP preemption time delay of 100 seconds on the primary edge port.

Device(config)#  interface TenGigabitEthernet 4/1
Device(config-if)#  rep preempt delay 100

rep preempt segment

To manually start REP VLAN load balancing on a segment, use the rep preempt segment command in privileged EXEC mode.

rep preempt segment segment-id

Syntax Description


`segment-id`	ID of the REP segment. The range is from 1 to 1024.

Command Default

Manual preemption is the default behavior.

Command Modes

Privileged EXEC (#)

Command History


Release	Modification
	This command was introduced

Usage Guidelines

Enter this command on the segment, which has the primary edge port on the router.

Ensure that all the other segment configuration is completed before setting preemption for VLAN load balancing. When you enter the rep preempt segment segment-id command, a confirmation message appears before the command is executed because preemption for VLAN load balancing can disrupt the network.

If you do not enter the rep preempt delay seconds command in interface configuration mode on the primary edge port to configure a preemption time delay, the default configuration is to manually trigger VLAN load balancing on the segment. Use the show rep topology privileged EXEC command to see which port in the segment is the primary edge port.

If you do not configure VLAN load balancing, entering this command results in the default behavior-the primary edge port blocks all VLANs.

You configure VLAN load balancing by entering the rep block port command in interface configuration mode on the REP primary edge port before you manually start preemption.

Examples

The following example shows how to manually trigger REP preemption on segment 100.

Device#  rep preempt segment 100

rep segment

To enable REP on the interface and to assign a segment ID to the interface, use the rep segment command in interface configuration mode. To disable REP on the interface, use the no form of this command.

rep segment segment-id [ edge [ no-neighbor] [ primary] ] [ preferred]

no rep segment

Syntax Description

segment-id

Segment for which REP is enabled. Assign a segment ID to the interface. The range is from 1 to 1024.

edge

(Optional) Configures the port as an edge port. Each segment has only two edge ports.

no-neighbor

(Optional) Specifies the segment edge as one with no external REP neighbor.

primary

(Optional) Specifies that the port is the primary edge port where you can configure VLAN load balancing. A segment has only one primary edge port.

preferred

(Optional) Specifies that the port is the preferred alternate port or the preferred port for VLAN load balancing.

Note

Configuring a port as preferred does not guarantee that it becomes the alternate port; it merely gives it a slight edge among equal contenders. The alternate port is usually a previously failed port.

Command Default

REP is disabled on the interface.

Command Modes

Interface configuration (config-if)

Command History


Release	Modification
	This command was introduced

Usage Guidelines

REP ports must be a Layer 2 IEEE 802.1Q port or 802.1AD port. You must configure two edge ports on each REP segment, a primary edge port and a port to act as a secondary edge port.

If REP is enabled on two ports on a router, both ports must be either regular segment ports or edge ports. REP ports follow these rules:

If only one port on a router is configured in a segment, the port should be an edge port.
If two ports on a router belong to the same segment, both ports must be regular segment ports.
If two ports on a router belong to the same segment and one is configured as an edge port and one as a regular segment port (a misconfiguration), the edge port is treated as a regular segment port.

REP interfaces come up in a blocked state and remain in a blocked state until notified that it is safe to unblock. Be aware of this to avoid sudden connection losses.

When REP is enabled on an interface, the default is for the port to be a regular segment port.

Examples

The following example shows how to enable REP on a regular (nonedge) segment port.

Device(config)#  interface TenGigabitEthernet 4/1
Device(config-if)#  rep segment 100

The following example shows how to enable REP on a port and identify the port as the REP primary edge port.

Device(config)#  interface TenGigabitEthernet 4/1
Device(config-if)#  rep segment 100 edge primary

The following example shows how to enable REP on a port and identify the port as the REP secondary edge port.

Device(config)#  interface TenGigabitEthernet 4/1
Device(config-if)#  rep segment 100 edge

The following example shows how to enable REP as an edge no-neighbor port.

Device(config)#  interface TenGigabitEthernet 4/1
Device(config-if)#  rep segment 1 edge no-neighbor primary

rep stcn

To configure a REP edge port to send segment topology change notifications (STCNs) to another interface or to other segments, use the rep stcn command in interface configuration mode. To disable the sending of STCNs to the interface or to the segment, use the no form of this command.

rep stcn { interface interface-id | segment segment-id-list}

no rep stcn { interface | segment}

Syntax Description


interface `interface-id`	Specifies a physical interface or port channel to receive STCNs.
segment `segment-id-list`	Specifies one REP segment or a list of segments to receive STCNs. The segment range is from 1 to 1024. You can also configure a sequence of segments (for example 3 to 5, 77, 100).

Command Default

Transmission of STCNs to other interfaces or segments is disabled.

Command Modes

Interface configuration (config-if)

Command History


Release	Modification
	This command was introduced

Usage Guidelines

Enter this command on a segment edge port to send STCNs to one or more segments or to an interface. You can verify your settings by entering the show interfaces rep detail privileged EXEC command.

Examples

The following example shows how to configure a REP edge port to send STCNs to segments 25 to 50.

Device(config)#  interface TenGigabitEthernet 4/1
Device(config-if)#   rep stcn segment 25-50

show etherchannel

To display EtherChannel information for a channel, use the show etherchannel command in user EXEC mode.

show etherchannel [channel-group-number | {detail | port | port-channel | protocol | summary }]| [detail | load-balance | port | port-channel | protocol | summary]

Syntax Description


`channel-group-number`
detail	(Optional) Displays detailed EtherChannel information.
load-balance	(Optional) Displays the load-balance or frame-distribution scheme among ports in the port channel.
port	(Optional) Displays EtherChannel port information.
port-channel	(Optional) Displays port-channel information.
protocol	(Optional) Displays the protocol that is being used in the channel.
summary	(Optional) Displays a one-line summary per channel group.

Command Default

None

Command Modes

User EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

If you do not specify a channel group number, all channel groups are displayed.

Examples

This is an example of output from the show etherchannel channel-group-number detail command:

Device> show etherchannel 1 detail
Group state = L2
Ports: 2   Maxports = 16
Port-channels: 1 Max Port-channels = 16
Protocol:      LACP
                   Ports in the group:
                   -------------------
Port: Gi1/0/1
------------
Port state    = Up Mstr In-Bndl
Channel group = 1        Mode  = Active        Gcchange = -
Port-channel  =          Po1GC = -             Pseudo port-channel = Po1
Port index    =          0Load = 0x00          Protocol = LACP

Flags: S - Device is sending Slow LACPDUs   F - Device is sending fast LACPDU
       A - Device is in active mode.        P - Device is in passive mode.

Local information:
                         LACP port   Admin   Oper   Port   Port
Port     Flags   State   Priority    Key     Key    Number State
Gi1/0/1   SA      bndl     32768      0x1     0x1    0x101  0x3D
Gi1/0/2    A      bndl     32768      0x0     0x1    0x0    0x3D

Age of the port in the current state: 01d:20h:06m:04s

                   Port-channels in the group:
                   ----------------------

Port-channel: Po1   (Primary Aggregator)

Age of the Port-channel = 01d:20h:20m:26s
Logical slot/port = 10/1          Number of ports = 2
HotStandBy port   = null
Port state        = Port-channel Ag-Inuse
Protocol          = LACP

Ports in the Port-channel:

Index  Load   Port      EC state        No of bits
------+------+------+------------------+-----------
 0      00    Gi1/0/1    Active           0
 0      00    Gi1/0/2    Active           0

Time since last port bundled:   01d:20h:24m:44s   Gi1/0/2

This is an example of output from the show etherchannel channel-group-number summary command:

Device> show etherchannel 1 summary
Flags: D - down P - in port-channel
       I - stand-alone s - suspended
       H - Hot-standby (LACP only)
       R - Layer3 S - Layer2
       u - unsuitable for bundling
       U - in use f - failed to allocate aggregator
       d - default port

Number of channel-groups in use: 1
Number of aggregators: 1

Group  Port-channel  Protocol    Ports
------+-------------+-----------+----------------------------------------
 1     Po1(SU)       LACP        Gi1/0/1(P) Gi1/0/2(P)

This is an example of output from the show etherchannel channel-group-number port-channel command:

Device> show etherchannel 1 port-channel
Port-channels in the group:
----------------------
Port-channel: Po1 (Primary Aggregator)
------------
Age of the Port-channel = 01d:20h:24m:50s
Logical slot/port = 10/1 Number of ports = 2
Logical slot/port = 10/1 Number of ports = 2
Port state = Port-channel Ag-Inuse
Protocol = LACP

Ports in the Port-channel:

Index  Load   Port   EC state           No of bits
------+------+------+------------------+-----------
 0      00    Gi1/0/1 Active             0
 0      00    Gi1/0/2 Active             0

Time since last port bundled: 01d:20h:24m:44s Gi1/0/2

This is an example of output from show etherchannel protocol command:

Device# show etherchannel protocol
Channel-group listing:
-----------------------
Group: 1
----------
Protocol: LACP
Group: 2
----------
Protocol: PAgP

show interfaces rep detail

To display detailed REP configuration and status for all the interfaces or the specified interface, including the administrative VLAN, use the show interfaces rep detail command in privileged EXEC mode.

show interfaces [ interface-id] rep detail

Syntax Description


`interface-id`	(Optional) Physical interface used to display the port ID.

Command Modes

Privileged EXEC (#)

Command History


Release	Modification
	This command was introduced

Usage Guidelines

Enter this command on a segment edge port to send STCNs to one or more segments or to an interface. You can verify your settings by entering the show interfaces rep detail privileged EXEC command.

Examples

The following example shows how to display the REP configuration and status for a specified interface.

Device#  show interfaces TenGigabitEthernet4/1 rep detail

TenGigabitEthernet4/1 REP enabled
Segment-id: 3 (Primary Edge)
PortID: 03010015FA66FF80
Preferred flag: No
Operational Link Status: TWO_WAY
Current Key: 02040015FA66FF804050
Port Role: Open
Blocked VLAN: <empty>
Admin-vlan: 1
Preempt Delay Timer: disabled
Configured Load-balancing Block Port: none
Configured Load-balancing Block VLAN: none
STCN Propagate to: none
LSL PDU rx: 999, tx: 652
HFL PDU rx: 0, tx: 0
BPA TLV rx: 500, tx: 4
BPA (STCN, LSL) TLV rx: 0, tx: 0
BPA (STCN, HFL) TLV rx: 0, tx: 0
EPA-ELECTION TLV rx: 6, tx: 5
EPA-COMMAND TLV rx: 0, tx: 0
EPA-INFO TLV rx: 135, tx: 136

show lacp

To display Link Aggregation Control Protocol (LACP) channel-group information, use the show lacp command in user EXEC mode.

show lacp [channel-group-number] {counters | internal | neighbor | sys-id}

Syntax Description


`channel-group-number`
counters	Displays traffic information.
internal	Displays internal information.
neighbor	Displays neighbor information.
sys-id	Displays the system identifier that is being used by LACP. The system identifier consists of the LACP system priority and the device MAC address.

Command Default

None

Command Modes

User EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

You can enter any show lacp command to display the active channel-group information. To display specific channel information, enter the show lacp command with a channel-group number.

If you do not specify a channel group, information for all channel groups appears.

You can enter the channel-group-number to specify a channel group for all keywords except sys-id .

Examples

This is an example of output from the show lacp counters user EXEC command. The table that follows describes the fields in the display.

Device> show lacp counters
              LACPDUs        Marker     Marker Response   LACPDUs
Port        Sent  Recv     Sent  Recv     Sent  Recv     Pkts  Err
---------------------------------------------------------------------
Channel group:1
Gi2/0/1      19    10        0    0         0    0        0
Gi2/0/2      14    6         0    0         0    0        0

Table 1. show lacp counters Field Descriptions
Field	Description
LACPDUs Sent and Recv	The number of LACP packets sent and received by a port.
Marker Sent and Recv	The number of LACP marker packets sent and received by a port.
Marker Response Sent and Recv	The number of LACP marker response packets sent and received by a port.
LACPDUs Pkts and Err	The number of unknown and illegal packets received by LACP for a port.

This is an example of output from the show lacp internal command:

Device> show lacp 1 internal
Flags:  S - Device is requesting Slow LACPDUs
        F - Device is requesting Fast LACPDUs
        A - Device is in Active mode       P - Device is in Passive mode

Channel group 1
                           LACP port    Admin    Oper    Port     Port
Port      Flags   State    Priority     Key      Key     Number   State
Gi2/0/1    SA      bndl     32768         0x3     0x3       0x4    0x3D
Gi2/0/2    SA      bndl     32768         0x3     0x3       0x5    0x3D

The following table describes the fields in the display:

Table 2. show lacp internal Field Descriptions

Field

Description

State

State of the specific port. These are the allowed values:

– —Port is in an unknown state.
bndl—Port is attached to an aggregator and bundled with other ports.
susp—Port is in a suspended state; it is not attached to any aggregator.
hot-sby—Port is in a hot-standby state.
indiv—Port is incapable of bundling with any other port.
indep—Port is in an independent state (not bundled but able to handle data traffic. In this case, LACP is not running on the partner port).
down—Port is down.

LACP Port Priority

Port priority setting. LACP uses the port priority to put ports in standby mode when there is a hardware limitation that prevents all compatible ports from aggregating.

Admin Key

Administrative key assigned to this port. LACP automatically generates an administrative key value as a hexadecimal number. The administrative key defines the ability of a port to aggregate with other ports. A port’s ability to aggregate with other ports is determined by the port physical characteristics (for example, data rate and duplex capability) and configuration restrictions that you establish.

Oper Key

Runtime operational key that is being used by this port. LACP automatically generates this value as a hexadecimal number.

Port Number

Port number.

Port State

State variables for the port, encoded as individual bits within a single octet with these meanings:

bit0: LACP_Activity
bit1: LACP_Timeout
bit2: Aggregation
bit3: Synchronization
bit4: Collecting
bit5: Distributing
bit6: Defaulted
bit7: Expired

Note

In the list above, bit7 is the MSB and bit0 is the LSB.

This is an example of output from the show lacp neighbor command:

Device> show lacp neighbor
Flags: S - Device is sending Slow LACPDUs  F - Device is sending Fast LACPDUs
       A - Device is in Active mode        P - Device is in Passive mode

Channel group 3 neighbors

Partner’s information:

          Partner                Partner               Partner
Port      System ID              Port Number   Age     Flags
Gi2/0/1   32768,0007.eb49.5e80   0xC             19s    SP

          LACP Partner           Partner       Partner
          Port Priority          Oper Key      Port State
          32768                  0x3           0x3C

Partner’s information:

          Partner                Partner               Partner
Port      System ID              Port Number   Age     Flags
Gi2/0/2   32768,0007.eb49.5e80   0xD             15s    SP

          LACP Partner           Partner       Partner
          Port Priority          Oper Key      Port State
          32768                  0x3           0x3C

This is an example of output from the show lacp sys-id command:

Device> show lacp sys-id
32765,0002.4b29.3a00

The system identification is made up of the system priority and the system MAC address. The first two bytes are the system priority, and the last six bytes are the globally administered individual MAC address associated to the system.

show pagp

To display Port Aggregation Protocol (PAgP) channel-group information, use the show pagp command in EXEC mode.

show pagp [channel-group-number] {counters | dual-active | internal | neighbor}

Syntax Description


`channel-group-number`
counters	Displays traffic information.
dual-active	Displays the dual-active status.
internal	Displays internal information.
neighbor	Displays neighbor information.

Command Default

None

Command Modes

User EXEC

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

You can enter any show pagp command to display the active channel-group information. To display the nonactive information, enter the show pagp command with a channel-group number.

Examples

This is an example of output from the show pagp 1 counters command:

Device> show pagp 1 counters
             Information        Flush
Port         Sent   Recv     Sent   Recv
----------------------------------------
Channel group: 1
  Gi1/0/1    45     42       0      0 
  Gi1/0/2    45     41       0      0

This is an example of output from the show pagp dual-active command:

Device> show pagp dual-active
PAgP dual-active detection enabled: Yes
PAgP dual-active version: 1.1
		
Channel group 1
          Dual-Active     Partner              Partner   Partner
Port      Detect Capable  Name                 Port      Version
Gi1/0/1   No              Device               Gi3/0/3   N/A
Gi1/0/2   No              Device               Gi3/0/4   N/A
		
<output truncated>

This is an example of output from the show pagp 1 internal command:

Device> show pagp 1 internal
Flags:  S - Device is sending Slow hello.  C - Device is in Consistent state.
        A - Device is in Auto mode.
Timers: H - Hello timer is running.        Q - Quit timer is running.
        S - Switching timer is running.    I - Interface timer is running.
		
Channel group 1
                                  Hello    Partner  PAgP     Learning  Group
Port        Flags State   Timers  Interval Count   Priority   Method  Ifindex
Gi1/0/1     SC    U6/S7   H       30s      1        128        Any      16
Gi1/0/2     SC    U6/S7   H       30s      1        128        Any      16

This is an example of output from the show pagp 1 neighbor command:

Device> show pagp 1 neighbor
		
Flags:  S - Device is sending Slow hello.  C - Device is in Consistent state.
        A - Device is in Auto mode.        P - Device learns on physical port.
		
Channel group 1 neighbors
            Partner              Partner          Partner           Partner Group
Port        Name                 Device ID        Port         Age  Flags   Cap.
Gi1/0/1     device-p2            0002.4b29.4600   Gi01//1        9s SC      10001 
Gi1/0/2     device-p2            0002.4b29.4600   Gi1/0/2       24s SC      10001

show platform etherchannel

To display platform-dependent EtherChannel information, use the show platform etherchannel command in privileged EXEC mode.

show platform etherchannel channel-group-number {group-mask | load-balance mac src-mac dst-mac [ip src-ip dst-ip [port src-port dst-port]]} [switch switch-number]

Syntax Description


`channel-group-number`	Channel group number. The range is 1 to 128.
group-mask	Displays EtherChannel group mask.
load-balance	Tests EtherChannel load-balance hash algorithm.
mac `src-mac` `dst-mac`	Specifies the source and destination MAC addresses.
ip `src-ip` `dst-ip`	(Optional) Specifies the source and destination IP addresses.
port `src-port` `dst-port`	(Optional) Specifies the source and destination layer port numbers.
switch `switch-number`	(Optional) Specifies the stack member.

Command Default

None

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

Use this command only when you are working directly with a technical support representative while troubleshooting a problem.

Do not use this command unless a technical support representative asks you to do so.

show platform pm

To display platform-dependent port manager information, use the show platform pm command in privileged EXEC mode.

Command Default

None

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

Use this command only when you are working directly with your technical support representative while troubleshooting a problem.

Do not use this command unless your technical support representative asks you to do so.

show rep topology

To display REP topology information for a segment or for all segments, including the primary and secondary edge ports in the segment, use the show rep topology command in privileged EXEC mode.

show rep topology [ segment segment-id] [ archive] [ detail]

Syntax Description


segment `segment-id`	(Optional) Specifies the segment for which to display REP topology information. The ID range is from 1 to 1024.
archive	(Optional) Displays the previous topology of the segment. This keyword is useful for troubleshooting a link failure.
detail	(Optional) Displays detailed REP topology information.

Command Modes

Privileged EXEC (#)

Command History


Release	Modification
	This command was introduced

Examples

The following is sample output from the show rep topology command.

Device#  show rep topology

REP Segment 1
BridgeName       PortName   Edge Role
---------------- ---------- ---- ----
10.64.106.63     Te5/4      Pri  Open
10.64.106.228    Te3/4           Open
10.64.106.228    Te3/3           Open
10.64.106.67     Te4/3           Open
10.64.106.67     Te4/4           Alt 
10.64.106.63     Te4/4      Sec  Open

REP Segment 3
BridgeName       PortName   Edge Role
---------------- ---------- ---- ----
10.64.106.63     Gi50/1     Pri  Open
SVT_3400_2       Gi0/3           Open
SVT_3400_2       Gi0/4           Open
10.64.106.68     Gi40/2          Open
10.64.106.68     Gi40/1          Open
10.64.106.63     Gi50/2     Sec  Alt

The following is sample output from the show rep topology detail command.

Device#  show rep topology detail

REP Segment 1
10.64.106.63, Te5/4 (Primary Edge)
  Open Port, all vlans forwarding
  Bridge MAC: 0005.9b2e.1700
  Port Number: 010
  Port Priority: 000
  Neighbor Number: 1 / [-6]
10.64.106.228, Te3/4 (Intermediate)
  Open Port, all vlans forwarding
  Bridge MAC: 0005.9b1b.1f20
  Port Number: 010
  Port Priority: 000
  Neighbor Number: 2 / [-5]
10.64.106.228, Te3/3 (Intermediate)
  Open Port, all vlans forwarding
  Bridge MAC: 0005.9b1b.1f20
  Port Number: 00E
  Port Priority: 000
  Neighbor Number: 3 / [-4]
10.64.106.67, Te4/3 (Intermediate)
  Open Port, all vlans forwarding
  Bridge MAC: 0005.9b2e.1800
  Port Number: 008
  Port Priority: 000
  Neighbor Number: 4 / [-3]
10.64.106.67, Te4/4 (Intermediate)
  Alternate Port, some vlans blocked
  Bridge MAC: 0005.9b2e.1800
  Port Number: 00A
  Port Priority: 000
  Neighbor Number: 5 / [-2]
10.64.106.63, Te4/4 (Secondary Edge)
  Open Port, all vlans forwarding
  Bridge MAC: 0005.9b2e.1700
  Port Number: 00A
  Port Priority: 000
  Neighbor Number: 6 / [-1]

show udld

To display UniDirectional Link Detection (UDLD) administrative and operational status for all ports or the specified port, use the show udld command in user EXEC mode.

show udld neighbors

Syntax Description


Auto-Template	(Optional) Displays UDLD operational status of the auto-template interface. The range is from 1 to 999.
Capwap	(Optional) Displays UDLD operational status of the CAPWAP interface. The range is from 0 to 2147483647.
GigabitEthernet	(Optional) Displays UDLD operational status of the GigabitEthernet interface. The range is from 0 to 9.
GroupVI	(Optional) Displays UDLD operational status of the group virtual interface. The range is from 1 to 255.
InternalInterface	(Optional) Displays UDLD operational status of the internal interface. The range is from 0 to 9.
Loopback	(Optional) Displays UDLD operational status of the loopback interface. The range is from 0 to 2147483647.
Null	(Optional) Displays UDLD operational status of the null interface.
Port-channel	(Optional) Displays UDLD operational status of the Ethernet channel interfaces. The range is from 1 to 128.
TenGigabitEthernet	(Optional) Displays UDLD operational status of the Ten Gigabit Ethernet interface. The range is from 0 to 9.
Tunnel	(Optional) Displays UDLD operational status of the tunnel interface. The range is from 0 to 2147483647.
Vlan	(Optional) Displays UDLD operational status of the VLAN interface. The range is from 1 to 4095.
`interface-id`	(Optional) ID of the interface and port number. Valid interfaces include physical ports, VLANs, and port channels.
neighbors	(Optional) Displays neighbor information only.

Command Default

None

Command Modes

User EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

If you do not enter an interface ID, administrative and operational UDLD status for all interfaces appear.

Examples

This is an example of output from the show udld interface-id command. For this display, UDLD is enabled on both ends of the link, and UDLD detects that the link is bidirectional. The table that follows describes the fields in this display.

Device> show udld gigabitethernet2/0/1
Interface gi2/0/1
---
Port enable administrative configuration setting: Follows device default
Port enable operational state: Enabled
Current bidirectional state: Bidirectional
Current operational state: Advertisement - Single Neighbor detected
Message interval: 60
Time out interval: 5
Entry 1
Expiration time: 146
Device ID: 1
Current neighbor state: Bidirectional
Device name: Switch-A
Port ID: Gi2/0/1
Neighbor echo 1 device: Switch-B
Neighbor echo 1 port: Gi2/0/2
Message interval: 5
CDP Device name: Switch-A

Table 3. show udld Field Descriptions
Field	Description
Interface	The interface on the local device configured for UDLD.
Port enable administrative configuration setting	How UDLD is configured on the port. If UDLD is enabled or disabled, the port enable configuration setting is the same as the operational enable state. Otherwise, the enable operational setting depends on the global enable setting.
Port enable operational state	Operational state that shows whether UDLD is actually running on this port.
Current bidirectional state	The bidirectional state of the link. An unknown state appears if the link is down or if it is connected to an UDLD-incapable device. A bidirectional state appears if the link is a normal two-way connection to a UDLD-capable device. All other values mean miswiring.
Current operational state	The current phase of the UDLD state machine. For a normal bidirectional link, the state machine is most often in the Advertisement phase.
Message interval	How often advertisement messages are sent from the local device. Measured in seconds.
Time out interval	The time period, in seconds, that UDLD waits for echoes from a neighbor device during the detection window.
Entry 1	Information from the first cache entry, which contains a copy of echo information received from the neighbor.
Expiration time	The amount of time in seconds remaining before this cache entry is aged out.
Device ID	The neighbor device identification.
Current neighbor state	The neighbor’s current state. If both the local and neighbor devices are running UDLD normally, the neighbor state and local state should be bidirectional. If the link is down or the neighbor is not UDLD-capable, no cache entries appear.
Device name	The device name or the system serial number of the neighbor. The system serial number appears if the device name is not set or is set to the default (Switch).
Port ID	The neighbor port ID enabled for UDLD.
Neighbor echo 1 device	The device name of the neighbors’ neighbor from which the echo originated.
Neighbor echo 1 port	The port number ID of the neighbor from which the echo originated.
Message interval	The rate, in seconds, at which the neighbor is sending advertisement messages.
CDP device name	The CDP device name or the system serial number. The system serial number appears if the device name is not set or is set to the default (Switch).

This is an example of output from the show udld neighbors command:

Device# show udld neighbors
Port     Device Name          Device ID  Port-ID  OperState
-------- -------------------- ---------- -------- --------------
Gi2/0/1  Switch-A             1          Gi2/0/1  Bidirectional
Gi3/0/1  Switch-A             2          Gi3/0/1  Bidirectional

switchport

To put an interface that is in Layer 3 mode into Layer 2 mode for Layer 2 configuration, use the switchport command in interface configuration mode. To put an interface in Layer 3 mode, use the no form of this command.

switchport

no switchport

Syntax Description

This command has no arguments or keywords.

Command Default

By default, all interfaces are in Layer 2 mode.

Command Modes

Interface configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

Use the no switchport command (without parameters) to set the interface to the routed-interface status and to erase all Layer 2 configurations. You must use this command before assigning an IP address to a routed port.

Note

This command is not supported on devices running the LAN Base feature set.

Entering the no switchport command shuts the port down and then reenables it, which might generate messages on the device to which the port is connected.

When you put an interface that is in Layer 2 mode into Layer 3 mode (or the reverse), the previous configuration information related to the affected interface might be lost, and the interface is returned to its default configuration.

Note

If an interface is configured as a Layer 3 interface, you must first enter the switchport command to configure the interface as a Layer 2 port. Then you can enter the switchport access vlan and switchport mode commands.

The switchport command is not used on platforms that do not support Cisco-routed ports. All physical ports on such platforms are assumed to be Layer 2-switched interfaces.

You can verify the port status of an interface by entering the show running-config privileged EXEC command.

Examples

This example shows how to cause an interface to cease operating as a Layer 2 port and become a Cisco-routed port:

Device(config-if)# no switchport

This example shows how to cause the port interface to cease operating as a Cisco-routed port and convert to a Layer 2 switched interface:

Device(config-if)# switchport

switchport access vlan

To configure a port as a static-access port, use the switchport access vlan command in interface configuration mode. To reset the access mode to the default VLAN mode for the device, use the no form of this command.

switchport access vlan {vlan-id}

no switchport access vlan

Syntax Description


`vlan-id`	VLAN ID of the access mode VLAN; the range is 1 to 4094.

Command Default

The default access VLAN and trunk interface native VLAN is a default VLAN corresponding to the platform or interface hardware.

Command Modes

Interface configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

The port must be in access mode before the switchport access vlan command can take effect.

If the switchport mode is set to access vlan vlan-id , the port operates as a member of the specified VLAN. An access port can be assigned to only one VLAN.

The no switchport access command resets the access mode VLAN to the appropriate default VLAN for the device.

Examples

This example shows how to change a switched port interface that is operating in access mode to operate in VLAN 2 instead of the default VLAN:

Device(config-if)# switchport access vlan 2

switchport mode

To configure the VLAN membership mode of a port, use the switchport mode command in interface configuration mode. To reset the mode to the appropriate default for the device, use the no form of this command.

switchport mode {access | dynamic | {auto | desirable} | trunk}

noswitchport mode {access | dynamic | {auto | desirable} | trunk}

Syntax Description


access	Sets the port to access mode (either static-access or dynamic-access depending on the setting of the switchport access vlan interface configuration command). The port is set to access unconditionally and operates as a nontrunking, single VLAN interface that sends and receives nonencapsulated (non-tagged) frames. An access port can be assigned to only one VLAN.
dynamic auto	Sets the port trunking mode dynamic parameter to auto to specify that the interface convert the link to a trunk link. This is the default switchport mode.
dynamic desirable	Sets the port trunking mode dynamic parameter to desirable to specify that the interface actively attempt to convert the link to a trunk link.
trunk	Sets the port to trunk unconditionally. The port is a trunking VLAN Layer 2 interface. The port sends and receives encapsulated (tagged) frames that identify the VLAN of origination. A trunk is a point-to-point link between two devices or between a device and a router.

Command Default

The default mode is dynamic auto .

Command Modes

Interface configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

A configuration that uses the access ,or trunk keywords takes effect only when you configure the port in the appropriate mode by using the switchport mode command. The static-access and trunk configuration are saved, but only one configuration is active at a time.

When you enter access mode, the interface changes to permanent nontrunking mode and negotiates to convert the link into a nontrunk link even if the neighboring interface does not agree to the change.

When you enter trunk mode, the interface changes to permanent trunking mode and negotiates to convert the link into a trunk link even if the interface connecting to it does not agree to the change.

When you enter dynamic auto mode, the interface converts the link to a trunk link if the neighboring interface is set to trunk or desirable mode.

When you enter dynamic desirable mode, the interface becomes a trunk interface if the neighboring interface is set to trunk , desirable , or auto mode.

To autonegotiate trunking, the interfaces must be in the same VLAN Trunking Protocol (VTP) domain. Trunk negotiation is managed by the Dynamic Trunking Protocol (DTP), which is a point-to-point protocol. However, some internetworking devices might forward DTP frames improperly, which could cause misconfigurations. To avoid this problem, configure interfaces connected to devices that do not support DTP to not forward DTP frames, which turns off DTP.

If you do not intend to trunk across those links, use the switchport mode access interface configuration command to disable trunking.
To enable trunking to a device that does not support DTP, use the switchport mode trunk and switchport nonegotiate interface configuration commands to cause the interface to become a trunk but to not generate DTP frames.

Access ports and trunk ports are mutually exclusive.

The IEEE 802.1x feature interacts with switchport modes in these ways:

If you try to enable IEEE 802.1x on a trunk port, an error message appears, and IEEE 802.1x is not enabled. If you try to change the mode of an IEEE 802.1x-enabled port to trunk, the port mode is not changed.
If you try to enable IEEE 802.1x on a port set to dynamic auto or dynamic desirable, an error message appears, and IEEE 802.1x is not enabled. If you try to change the mode of an IEEE 802.1x-enabled port to dynamic auto or dynamic desirable, the port mode is not changed.
If you try to enable IEEE 802.1x on a dynamic-access (VLAN Query Protocol [VQP]) port, an error message appears, and IEEE 802.1x is not enabled. If you try to change an IEEE 802.1x-enabled port to dynamic VLAN assignment, an error message appears, and the VLAN configuration is not changed.

You can verify your settings by entering the show interfaces interface-id switchport privileged EXEC command and examining information in the Administrative Mode and Operational Mode rows.

Examples

This example shows how to configure a port for access mode:

Device(config)# interface gigabitethernet2/0/1
Device(config-if)# switchport mode access

This example shows how set the port to dynamic desirable mode:

Device(config)# interface gigabitethernet2/0/1
Device(config-if)# switchport mode dynamic desirable

This example shows how to configure a port for trunk mode:

Device(config)# interface gigabitethernet2/0/1
Device(config-if)# switchport mode trunk

switchport nonegotiate

To specify that Dynamic Trunking Protocol (DTP) negotiation packets are not sent on the Layer 2 interface, use the switchport nonegotiate command in interface configuration mode. Use the no form of this command to return to the default setting.

switchport nonegotiate

no switchport nonegotiate

Syntax Description

This command has no arguments or keywords.

Command Default

The default is to use DTP negotiation to learn the trunking status.

Command Modes

Interface configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

The no switchport nonegotiate command removes nonegotiate status.

This command is valid only when the interface switchport mode is access or trunk (configured by using the switchport mode access or the switchport mode trunk interface configuration command). This command returns an error if you attempt to execute it in dynamic (auto or desirable) mode.

Internetworking devices that do not support DTP might forward DTP frames improperly and cause misconfigurations. To avoid this problem, turn off DTP by using the switchport nonegotiate command to configure the interfaces connected to devices that do not support DTP to not forward DTP frames.

When you enter the switchport nonegotiate command, DTP negotiation packets are not sent on the interface. The device does or does not trunk according to the mode parameter: access or trunk.

If you do not intend to trunk across those links, use the switchport mode access interface configuration command to disable trunking.
To enable trunking on a device that does not support DTP, use the switchport mode trunk and switchport nonegotiate interface configuration commands to cause the interface to become a trunk but to not generate DTP frames.

Examples

This example shows how to cause a port to refrain from negotiating trunking mode and to act as a trunk or access port (depending on the mode set):

Device(config)# interface gigabitethernet2/0/1
Device(config-if)# switchport nonegotiate

You can verify your setting by entering the show interfaces interface-id switchport privileged EXEC command.

switchport voice vlan

To configure voice VLAN on the port, use the switchport voice vlan command in interface configuration mode. To return to the default setting, use the no form of this command.

switchport voice vlan { vlan-id|dot1p|none|untagged|name vlan_name}

no switchport voice vlan

Syntax Description


`vlan-id`	The VLAN to be used for voice traffic. The range is 1 to 4094. By default, the IP phone forwards the voice traffic with an IEEE 802.1Q priority of 5.
dot1p	Configures the telephone to use IEEE 802.1p priority tagging and uses VLAN 0 (the native VLAN). By default, the Cisco IP phone forwards the voice traffic with an IEEE 802.1p priority of 5.
none	Does not instruct the IP telephone about the voice VLAN. The telephone uses the configuration from the telephone key pad.
untagged	Configures the telephone to send untagged voice traffic. This is the default for the telephone.
name `vlan_name`	(Optional) Specifies the VLAN name to be used for voice traffic. You can enter up to 128 characters.

Command Default

The default is not to automatically configure the telephone (none).

The telephone default is not to tag frames.

Command Modes

Interface configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.
	Option to specify a VLAN name for voice VLAN. The 'name ' keyword was added.

Usage Guidelines

You should configure voice VLAN on Layer 2 access ports.

You must enable Cisco Discovery Protocol (CDP) on the switch port connected to the Cisco IP phone for the device to send configuration information to the phone. CDP is enabled by default globally and on the interface.

When you enter a VLAN ID, the IP phone forwards voice traffic in IEEE 802.1Q frames, tagged with the specified VLAN ID. The device puts IEEE 802.1Q voice traffic in the voice VLAN.

When you select dot1p , none , or untagged , the device puts the indicated voice traffic in the access VLAN.

In all configurations, the voice traffic carries a Layer 2 IP precedence value. The default is 5 for voice traffic.

When you enable port security on an interface that is also configured with a voice VLAN, set the maximum allowed secure addresses on the port to 2. When the port is connected to a Cisco IP phone, the IP phone requires one MAC address. The Cisco IP phone address is learned on the voice VLAN, but not on the access VLAN. If you connect a single PC to the Cisco IP phone, no additional MAC addresses are required. If you connect more than one PC to the Cisco IP phone, you must configure enough secure addresses to allow one for each PC and one for the Cisco IP phone.

If any type of port security is enabled on the access VLAN, dynamic port security is automatically enabled on the voice VLAN.

You cannot configure static secure MAC addresses in the voice VLAN.

A voice-VLAN port cannot be a private-VLAN port.

The Port Fast feature is automatically enabled when voice VLAN is configured. When you disable voice VLAN, the Port Fast feature is not automatically disabled.

Examples

This example show how to first populate the VLAN database by associating a VLAN ID with a VLAN name, and then configure the VLAN (using the name) on an interface, in the access mode: You can also verify your configuration by entering the show interfaces interface-id switchport in privileged EXEC command and examining information in the Voice VLAN: row.

Part 1 - Making the entry in the VLAN database:


Device# configure terminal
Device(config)# vlan 55
Device(config-vlan)# name test
Device(config-vlan)# end
Device#

Part 2 - Checking the VLAN database:

Device# show vlan id 55
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
55 test active 
VLAN Type  SAID   MTU  Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
---- ----- ------ ---- -----  ------ -------- --- -------- ------ ------
55   enet  100055 1500 -      -      -        -   -        0      0
Remote SPAN VLAN
----------------
Disabled
Primary Secondary Type Ports 
------- --------- ----------------- ------------------------------------------

Part 3- Assigning VLAN to the interface by using the name of the VLAN:

Device# configure terminal
Device(config)# interface gigabitethernet3/1/1
Device(config-if)# switchport mode access
Device(config-if)# switchport voice vlan name test
Device(config-if)# end
Device#

Part 4 - Verifying configuration:

Device# show running-config
interface gigabitethernet3/1/1
Building configuration...
Current configuration : 113 bytes
!
interface GigabitEthernet3/1/1
switchport voice vlan 55
switchport mode access
Switch#

Part 5 - Also can be verified in interface switchport:

Device# show interface GigabitEthernet3/1/1 switchport
Name: Gi3/1/1
Switchport: Enabled
Administrative Mode: static access
Operational Mode: static access
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: native
Negotiation of Trunking: Off
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Administrative Native VLAN tagging: enabled
Voice VLAN: 55 (test)
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk Native VLAN tagging: enabled
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk associations: none
Administrative private-vlan trunk mappings: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL
Unknown unicast blocked: disabled
Unknown multicast blocked: disabled
Appliance trust: none
Device#

udld

To enable aggressive or normal mode in the UniDirectional Link Detection (UDLD) and to set the configurable message timer time, use the udld command in global configuration mode. To disable aggressive or normal mode UDLD on all fiber-optic ports, use the no form of the command.

udld {aggressive | enable | message time message-timer-interval}

no udld {aggressive | enable | message}

Syntax Description


aggressive	Enables UDLD in aggressive mode on all fiber-optic interfaces.
enable	Enables UDLD in normal mode on all fiber-optic interfaces.
message time `message-timer-interval`	Configures the period of time between UDLD probe messages on ports that are in the advertisement phase and are determined to be bidirectional. The range is 1 to 90 seconds. The default is 15 seconds.

Command Default

UDLD is disabled on all interfaces.

The message timer is set at 15 seconds.

Command Modes

Global configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

UDLD supports two modes of operation: normal (the default) and aggressive. In normal mode, UDLD detects unidirectional links due to misconnected interfaces on fiber-optic connections. In aggressive mode, UDLD also detects unidirectional links due to one-way traffic on fiber-optic and twisted-pair links and due to misconnected interfaces on fiber-optic links. For information about normal and aggressive modes, see the Catalyst 2960-X Switch Layer 2 Configuration GuideCatalyst 2960-XR Switch Layer 2 Configuration Guide.

If you change the message time between probe packets, you are making a compromise between the detection speed and the CPU load. By decreasing the time, you can make the detection-response faster but increase the load on the CPU.

This command affects fiber-optic interfaces only. Use the udld interface configuration command to enable UDLD on other interface types.

You can use these commands to reset an interface shut down by UDLD:

The udld reset privileged EXEC command to reset all interfaces shut down by UDLD.
The shutdown and no shutdown interface configuration commands.
The no udld enable global configuration command followed by the udld {aggressive | enable} global configuration command to reenable UDLD globally.
The no udld port interface configuration command followed by the udld port or udld port aggressive interface configuration command to reenable UDLD on the specified interface.
The errdisable recovery cause udld and errdisable recovery interval interval global configuration commands to automatically recover from the UDLD error-disabled state.

Examples

This example shows how to enable UDLD on all fiber-optic interfaces:

Device(config)# udld enable

You can verify your setting by entering the show udld privileged EXEC command.

udld port

To enable UniDirectional Link Detection (UDLD) on an individual interface or to prevent a fiber-optic interface from being enabled by the udld global configuration command, use the udld port command in interface configuration mode. To return to the udld global configuration command setting or to disable UDLD if entered for a nonfiber-optic port, use the no form of this command.

udld port [aggressive]

no udld port [aggressive]

Syntax Description


aggressive	(Optional) Enables UDLD in aggressive mode on the specified interface.

Command Default

On fiber-optic interfaces, UDLD is disabled and fiber-optic interfaces enable UDLD according to the state of the udld enable or udld aggressive global configuration command.

On nonfiber-optic interfaces, UDLD is disabled.

Command Modes

Interface configuration

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

A UDLD-capable port cannot detect a unidirectional link if it is connected to a UDLD-incapable port of another device.

UDLD supports two modes of operation: normal (the default) and aggressive. In normal mode, UDLD detects unidirectional links due to misconnected interfaces on fiber-optic connections. In aggressive mode, UDLD also detects unidirectional links due to one-way traffic on fiber-optic and twisted-pair links and due to misconnected interfaces on fiber-optic links.

To enable UDLD in normal mode, use the udld port interface configuration command. To enable UDLD in aggressive mode, use the udld port aggressive interface configuration command.

Use the no udld port command on fiber-optic ports to return control of UDLD to the udld enable global configuration command or to disable UDLD on nonfiber-optic ports.

Use the udld port aggressive command on fiber-optic ports to override the setting of the udld enable or udld aggressive global configuration command. Use the no form on fiber-optic ports to remove this setting and to return control of UDLD enabling to the udld global configuration command or to disable UDLD on nonfiber-optic ports.

You can use these commands to reset an interface shut down by UDLD:

The udld reset privileged EXEC command resets all interfaces shut down by UDLD.
The shutdown and no shutdown interface configuration commands.
The no udld enable global configuration command, followed by the udld {aggressive | enable} global configuration command reenables UDLD globally.
The no udld port interface configuration command, followed by the udld port or udld port aggressive interface configuration command reenables UDLD on the specified interface.
The errdisable recovery cause udld and errdisable recovery interval interval global configuration commands automatically recover from the UDLD error-disabled state.

Examples

This example shows how to enable UDLD on an port:

Device(config)# interface gigabitethernet6/0/1
Device(config-if)# udld port

This example shows how to disable UDLD on a fiber-optic interface despite the setting of the udld global configuration command:

Device(config)# interface gigabitethernet6/0/1
Device(config-if)# no udld port

You can verify your settings by entering the show running-config or the show udld interface privileged EXEC command.

udld reset

To reset all interfaces disabled by UniDirectional Link Detection (UDLD) and permit traffic to begin passing through them again (though other features, such as spanning tree, Port Aggregation Protocol (PAgP), and Dynamic Trunking Protocol (DTP) still have their normal effects, if enabled), use the udld reset command in privileged EXEC mode.

udld reset

Syntax Description

This command has no arguments or keywords.

Command Default

None

Command Modes

Privileged EXEC

Command History


Release	Modification
Cisco IOS XE Everest 16.5.1a	This command was introduced.

Usage Guidelines

If the interface configuration is still enabled for UDLD, these ports begin to run UDLD again and are disabled for the same reason if the problem has not been corrected.

Examples

This example shows how to reset all interfaces disabled by UDLD:

Device# udld reset
1 ports shutdown by UDLD were reset.

Bias-Free Language

Results

Chapter: Layer 2/3

Layer 2/3

channel-group

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

channel-protocol

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

clear lacp

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

clear pagp

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

clear spanning-tree counters

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

clear spanning-tree detected-protocols

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

debug etherchannel

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

debug lacp

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

debug pagp

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

debug platform pm

Syntax Description

Command Default

Command Modes

Command History

Usage Guidelines

Examples

debug platform udld

Syntax Description

Command Default

Command Modes

Command History