Table Of Contents

Ethernet Interface Commands on Cisco IOS XR Software

carrier-delay

clear mac-accounting (Ethernet)

duplex full (Fast Ethernet)

duplex half (Fast Ethernet)

flow-control

interface FastEthernet

interface GigabitEthernet

interface TenGigE

l2protocol (Ethernet)

l2transport (Ethernet)

loopback (Ethernet)

mac-accounting

mac-address (Ethernet)

negotiation auto

packet-gap non-standard

show controllers (Ethernet)

show mac-accounting (Ethernet)

speed (Fast Ethernet)

Ethernet Interface Commands on Cisco IOS XR Software

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This module describes the Cisco IOS XR commands used to configure the Ethernet interfaces.

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Note This module does not include the commands for Management Ethernet interfaces. To configure a Management Ethernet interface for routing or modify the configuration of a Management Ethernet interface, use the commands described in the Management Ethernet Interface Commands on Cisco IOS XR Software module earlier in this document.

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carrier-delay

To delay the processing of hardware link down notifications, use the carrier-delay command in interface configuration mode.

carrier-delay {down milliseconds [up milliseconds] | up milliseconds [down milliseconds]}

Syntax Description

down milliseconds	Length of time, in milliseconds, to delay the processing of hardware link down notifications. Range is from 1 through 5000.
up milliseconds	Length of time, in milliseconds, to delay the processing of hardware link up notifications. Range is from 1 through 5000.

Defaults

No carrier-delay is used, and the upper layer protocols are notified as quickly as possible when a physical link goes down

Command Modes

Interface configuration

Command History

Release	Modification
Release 3.2	This command was first introduced on the Cisco CRS-1 and Cisco XR 12000 Series Router.
Release 3.3.0	No modification.
Release 3.4.0	The msec keyword was replaced by the down keyword, and the up milliseconds keyword argument was added.
Release 3.5.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

When you delay the processing of hardware link down notifications, the higher layer routing protocols are unaware of a link until that link is stable.

If the carrier-delay down milliseconds command is configured on a physical link that fails and cannot be recovered, link down detection is increased, and it may take longer for the routing protocols to re-route traffic around the failed link.

In the case of very small interface state flaps, running the carrier-delay down milliseconds command prevents the routing protocols from experiencing a route flap.

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Note Enter the show interface command to see the current state of the carrier-delay operation for an interface. No carrier-delay information is displayed if carrier-delay has not been configured on an interface.

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Task ID

Task ID	Operations
interface	read, write

Examples

The following example shows how to delay the processing of hardware link down notifications:

RP/0/RP0/CPU0:router(config-if)# carrier-delay down 10

The following example shows how to delay the processing of hardware link up and down notifications:

RP/0/RP0/CPU0:router(config-if)# carrier-delay up 100 down 100

Related Commands

Command	Description
dampening	Limits propagation of transient or frequently changing interface states on Interface Manager (IM) clients.

clear mac-accounting (Ethernet)

To clear Media Access Control (MAC) accounting statistics, use the clear mac-accounting command in EXEC mode.

clear mac-accounting {GigabitEthernet | TenGigE | FastEthernet} instance [location node-id]

Syntax Description

{GigabitEthernet | TenGigE | FastEthernet}	Type of Ethernet interface whose MAC accounting statistics you want to clear. Enter GigabitEthernet, TenGigE, or FastEthernet. Note Fast Ethernet interfaces are available only on the Cisco XR 12000 Series Router.
instance	Interface whose MAC accounting statistics you want to clear. The naming notation is rack/slot/module/port, and a slash between values is required as part of the notation. •rack—Chassis number of the rack. •slot—Physical slot number of the line card or modular services card. •module—Module number. A physical layer interface module (PLIM) is always 0. •port—Physical port number of the interface. The instance argument is entered in the rack/slot/module/port notation. Note For more information about the syntax for the router, use the question mark (?) online help function.
location node-id	(Optional) Clears MAC accounting statistics for the designated node. The node-id argument is entered in the rack/slot/module notation.

Defaults

No default behavior or values

Command Modes

EXEC

Command History

Release	Modification
Release 2.0	This command was first introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.
Release 3.4.0	No modification.
Release 3.5.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Task ID

Task ID	Operations
interface	read, write
basic-services	read, write

Examples

The following example shows how to clear all MAC accounting statistics for the TenGigE port at 1/0/0/1:

RP/0/RP0/CPU0:router# clear mac-accounting TenGigE 0/1/5/0 location 1/0/0/1

Related Commands

Command	Description
mac-accounting	Configures MAC accounting on an interface.
show mac-accounting (Ethernet)	Displays MAC accounting statistics for an interface.

duplex full (Fast Ethernet)

To configure full-duplex operation on a Fast Ethernet interface, use the duplex full command in interface configuration mode. To return the system to the default duplex operation, use the no form of the duplex full command.

duplex full

no duplex full

Syntax Description

This command has no arguments or keywords.

Defaults

If autonegotiation is disabled on an interface, then the default duplex operation is full duplex.

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	No modification.
Release 3.3.0	No modification.
Release 3.4.0	No modification.

Release 3.5.0

No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

The duplex full command automatically replaces the duplex half command if half duplex was previously configured on your router.

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Note The duplex full command and the duplex half command cannot be configured simultaneously.

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Task ID

Task ID	Operations
interface	read, write

Examples

The following example shows how to set the Fast Ethernet interface at full duplex:

RP/0/RP0/CPU0:router(config)# interface FastEthernet 0/2/0/0

RP/0/RP0/CPU0:router(config-if)# duplex full

Related Commands

Command	Description
duplex half (Fast Ethernet)	Configures half-duplex operation on a Fast Ethernet interface.
negotiation auto	Enables link autonegotiation on Gigabit Ethernet and Fast Ethernet interfaces.
show interfaces	Displays statistics for all interfaces configured on the router.
speed (Fast Ethernet)	Configures the speed for a Fast Ethernet interface.

duplex half (Fast Ethernet)

To configure half-duplex operation on a Fast Ethernet interface, use the duplex half command in interface configuration mode. To return the system to the default duplex operation, use the no form of the duplex half command.

duplex half

no duplex half

Syntax Description

This command has no arguments or keywords.

Defaults

If autonegotiation is disabled on an interface, then the default duplex operation is full duplex.

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	No modification.
Release 3.3.0	No modification.
Release 3.4.0	No modification.
Release 3.5.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

The duplex half command automatically replaces the duplex full command if full duplex was previously configured on your router.

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Note The duplex half command and the duplex full command cannot be configured simultaneously.

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Task ID

Task ID	Operations
interface	read, write

Examples

The following examples shows how to set the Fast Ethernet interface at half duplex:

RP/0/RP0/CPU0:router(config)# interface mgmteth 0/RP0/CPU0/0

RP/0/RP0/CPU0:router(config-if)# duplex half

Related Commands

Command	Description
duplex full (Fast Ethernet)	Configures full-duplex operation on a Fast Ethernet interface.
negotiation auto	Enables link autonegotiation on Gigabit Ethernet and Fast Ethernet interfaces.
show interfaces	Displays statistics for all interfaces configured on the router.
speed (Fast Ethernet)	Configures the speed for a Fast Ethernet interface.

flow-control

To enable the sending of flow-control pause frames, use the flow-control command in interface configuration mode. To disable flow control, use the no form of this command.

flow-control {bidirectional | egress | ingress}

no flow-control ingress {bidirectional | egress | ingress}

Syntax Description

bidirectional	Sends flow-control pause frames for both ingress and egress traffic.
egress	Sends flow-control pause frames for egress traffic.
ingress	Sends flow-control pause frames for ingress traffic.

Defaults

If autonegotiate is enabled on the interface, then the default is negotiated.

If autonegotiate is disabled on the interface, then the sending of flow-control pause frames is disabled for both egress and ingress traffic.

Command Modes

Interface configuration

Command History

Release	Modification
Release 3.0	This command was introduced on the Cisco CRS-1.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.
Release 3.4.0	No modification.
Release 3.5.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

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Note When you explicitly enable the sending of flow-control pause frames, the value you configured with the flow-control command overrides any autonegotiated value. This prevents a link from coming up if the value you set with the flow-control command conflicts with the allowable settings on the other end of the connection.

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Note The flow-control command is supported on Gigabit Ethernet, TenGigE, and FastEthernet interfaces only; the flow-control command is not supported on Management Ethernet Interfaces.

---

---

Note The flow-control command syntax options may vary, depending on the type of PLIM or SPA that is installed in your router.

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Task ID

Task ID	Operations
interface	read, write

Examples

The following example shows how to enable the sending of flow-control pause frames for ingress traffic on the TenGigE interface 0/3/0/0:

RP/0/RP0/CPU0:router(config)# interface TenGigE 0/3/0/0

RP/0/RP0/CPU0:router(config-if)# flow-control ingress

Related Commands

Command	Description
show interfaces	Displays statistics for all interfaces configured on the router.

interface FastEthernet

To enter interface configuration mode for a Fast Ethernet interface, use the interface FastEthernet command in global configuration mode. To delete a Fast Ethernet interface configuration, use the no form of this command.

interface FastEthernet instance

no interface FastEthernet instance

Syntax Description

instance

Physical interface instance. Naming notation is rack/slot/module/port, and a slash between values is required as part of the notation. •rack—Chassis number of the rack. •slot—Physical slot number of the card. •module—Module number. A physical layer interface module (PLIM) is always 0. •port—Physical port number of the interface. For more information about the syntax for the router, use the question mark (?) online help function.

Defaults

No default behavior or values

Command Modes

Global configuration

Command History

Release	Modification
Release 3.3.0	This command was introduced on the Cisco XR 12000 Series Router.
Release 3.4.0	No modification.
Release 3.5.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Task ID

Task ID	Operations
interface	read, write

Examples

The following example shows how to enter interface configuration mode for a Fast Ethernet interface:

RP/0/RP0/CPU0:router(config)# interface FastEthernet 0/2/0/0

RP/0/RP0/CPU0:router(config-if)#

Related Commands

Command	Description
show interfaces	Displays statistics for all interfaces configured on the router.

interface GigabitEthernet

To enter interface configuration mode for a Gigabit Ethernet interface, use the interface GigabitEthernet command in global configuration mode. To delete a Gigabit Ethernet interface configuration, use the no form of this command.

interface GigabitEthernet instance

no interface GigabitEthernet instance

Syntax Description

instance

Physical interface instance. Naming notation is rack/slot/module/port and a slash between values is required as part of the notation. •rack—Chassis number of the rack. •slot—Physical slot number of the card. •module—Module number. A physical layer interface module (PLIM) is always 0. •port—Physical port number of the interface. Note For more information about the syntax for the router, use the question mark (?) online help function.

Defaults

No default behavior or values

Command Modes

Global configuration

Command History

Release	Modification
Release 3.2	This command was introduced on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.
Release 3.4.0	No modification.
Release 3.5.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Task ID

Task ID	Operations
interface	read, write

Examples

The following example shows how to enter interface configuration mode for a Gigabit Ethernet interface:

RP/0/0/CPU0:router(config)# interface GigabitEthernet 0/4/0/0

RP/0/0/CPU0:router(config-if)#

Related Commands

Command	Description
show interfaces	Displays statistics for all interfaces configured on the router.

interface TenGigE

To enter interface configuration mode for a 10-Gigabit Ethernet interface, use the interface TenGigE command in global configuration mode. To delete a 10-Gigabit Ethernet interface configuration, use the no form of this command.

interface TenGigE instance

no interface TenGigE instance

Syntax Description

instance

Physical interface instance. Naming notation is rack/slot/module/port and a slash between values is required as part of the notation. –rack—Chassis number of the rack. –slot—Physical slot number of the card. –module—Module number. A physical layer interface module (PLIM) is always 0. –port—Physical port number of the interface. Note For more information about the syntax for the router, use the question mark (?) online help function.

Defaults

No default behavior or values

Command Modes

Global configuration

Command History

Release	Modification
Release 2.0	This command was introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.
Release 3.4.0	No modification.
Release 3.5.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Task ID

Task ID	Operations
interface	read, write

Examples

The following example shows how to enter interface configuration mode for a 10-Gigabit Ethernet interface:

RP/0/RP0/CPU0:router(config)# interface TenGigE 0/1/0/0

RP/0/RP0/CPU0:router(config-if)#

Related Commands

Command	Description
show interfaces	Displays statistics for all interfaces configured on the router.

l2protocol (Ethernet)

To configure Layer 2 protocol tunneling and protocol data unit (PDU) filtering on an Ethernet interface, use the l2protocol command in Layer 2 transport configuration mode. To disable a Layer 2 protocol tunneling and Layer 2 protocol data units configuration, use the no form of this command.

l2protocol {cdp | pvst | stp | vtp} {[tunnel] experimental bits | drop}

no l2protocol

Syntax Description

cdp	Configures Cisco Discovery Protocol (CDP) tunneling and data unit parameters for the Ethernet interface.
pvst	Configures VLAN spanning tree protocol tunneling and data unit parameters.
stp	Configures spanning tree protocol tunneling and data unit parameters for the Ethernet interface.
vtp	Configures VLAN trunk protocol tunneling and data unit parameters.
tunnel	Tunnels the packets associated with the specified protocol. When you specify the tunnel keyword, the packet destination MAC address is re-written with an alternative address before that packet is sent over a pseudowire. After the packet comes through the other end of the pseudowire, the alternative address reverts to the original destination MAC address.
experimental bits	Replaces the experimental bits in the MPLS header with the 802.1p bits from the MAC header and vice-versa.
drop	Drops packets associated with the specified protocol.

Command Default

All Layer 2 protocol data units are forwarded through the network without modification.

Command Modes

Layer 2 transport configuration

Command History

Release	Modification
Release 3.4.0	This command was first introduced on the Cisco CRS-1 and Cisco XR 12000 Series Router.
Release 3.5.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

Note The l2protocol command is available only when Layer 2 transport port mode is enabled on the interface with the l2transport command.

Task ID

Task ID	Operations
l2vpn	read, write

Examples

The following example shows how to configure an Ethernet interface to drop CDP packets:

RP/0/RP0/CPU0:router# configure

RP/0/RP0/CPU0:router(config)# interface TenGigE 0/0/0/1

RP/0/RP0/CPU0:router(config-if)# l2transport

RP/0/RP0/CPU0:router(config-if-l2)# l2protocol cdp drop

Related Commands

Command	Description
l2transport (Ethernet)	Enables Layer 2 transport port mode on an Ethernet interface and enters Layer 2 transport configuration mode.
show interfaces	Displays statistics for all interfaces configured on the router or for a specific node.

l2transport (Ethernet)

To enable Layer 2 transport port mode on an Ethernet interface and enter Layer 2 transport configuration mode, use the l2transport command in interface configuration mode for an Ethernet interface. To disable Layer 2 transport port mode on an Ethernet interface, use the no form of this command.

l2transport

no l2transport

Syntax Description

This command has no arguments or keywords.

Defaults

No default behavior or values

Command Modes

Interface configuration

Command History

Release	Modification
Release 3.4.0	This command was first introduced on the Cisco CRS-1and Cisco XR 12000 Series Router.
Release 3.5.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

When you issue the l2transport command in interface configuration mode, the CLI prompt changes to "config-if-l2," indicating that you have entered the Layer 2 transport configuration submode. In the following sample output, the question mark (?) online help function displays all the commands available under Layer 2 transport configuration submode for an Ethernet interface:

RP/0/RP0/CPU0:router#configure

RP/0/RP0/CPU0:router(config)# interface GigabitEthernet 0/1/5/0

RP/0/RP0/CPU0:router(config-if)#l2transport

RP/0/RP0/CPU0:router(config-if-l2)#?

  commit          Commit the configuration changes to running

  describe        Describe a command without taking real actions

  do              Run an exec command

  exit            Exit from this submode

  no              Negate a command or set its defaults

  service-policy  Configure QoS Service policy

  show            Show contents of configuration

RP/0/RP0/CPU0:router(config-if-l2)#

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Note The l2transport command is mutually exclusive with any Layer 3 interface configuration.

---

Task ID

Task ID	Operations
l2vpn	read, write

Examples

The following example shows how to enable Layer 2 transport port mode on an Ethernet interface and enter Layer 2 transport configuration mode:

RP/0/RP0/CPU0:router# configure

RP/0/RP0/CPU0:router(config)#interface GigabitEther 0/2/0/0

RP/0/RP0/CPU0:router(config-if)#l2transport

RP/0/RP0/CPU0:router(config-if-l2)#

Related Commands

Command	Description
show interfaces	Displays statistics for all interfaces configured on the router or for a specific node.
show l2vpn xconnect	Displays brief information on configured xconnects.

loopback (Ethernet)

To configure an Ethernet controller for loopback mode, use the loopback command in interface configuration mode. To disable loopback, use the no form of this command.

loopback {external | internal | line}

no loopback

Syntax Description

external	All IPv4 self-ping packets are sent out of the interface and looped back externally before being received on the ingress path.
internal	All packets will be looped back internally within the router before reaching an external cable.
line	Incoming network packets will be looped back through the external cable.

Defaults

Loopback mode is disabled.

Command Modes

Interface configuration

Command History

Release	Modification
Release 3.0	This command was introduced on the Cisco CRS-1.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.
Release 3.4.0	No modification.
Release 3.5.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

The loopback command is available for all Ethernet interface types (Gigabit Ethernet, 10-Gigabit Ethernet, and Fast Ethernet).

Two loopback operation modes are supported for diagnostic purposes: internal and line. In the terminal (internal) loopback, the sent signal is looped back to the receiver. In the facility (line) loopback, the signal received from the far end is looped back and sent on the line. The two loopback modes cannot be active at the same time. In normal operation mode, neither of the two loopback modes is enabled.

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Tip Use the loopback external command when an external loopback connector is attached to the interface.

---

Task ID

Task ID	Operations
interface	read, write

Examples

In the following example, all packets are looped back to the TenGigE controller:

RP/0/RP0/CPU0:router(config)# interface TenGigE 0/3/0/0

RP/0/RP0/CPU0:router(config-if)# loopback internal

mac-accounting

To generate accounting information for IP traffic based on the source and destination Media Access Control (MAC) addresses on LAN interfaces, use the mac-accounting command in interface configuration mode. To disable MAC accounting, use the no form of this command.

mac-accounting {egress | ingress}

Syntax Description

egress	Generates accounting information for IP traffic based on the destination MAC addresses (egress direction).
ingress	Generates accounting information for IP traffic based on the source MAC addresses (ingress direction).

Defaults

MAC accounting is disabled

Command Modes

Interface configuration

Command History

Release	Modification
Release 3.0	This command was first introduced on the Cisco CRS-1.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.
Release 3.4.0	No modification.
Release 3.5.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

The mac-accounting command calculates the total packet and byte counts for a LAN interface that receives or sends IPv4 packets to or from a unique MAC address.

Task ID

Task ID	Operations
interface	read, write

Examples

The following example shows how to enable MAC accounting for the source MAC address on the ingress direction:

RP/0/RP0/CPU0:router(config-if)# mac-accounting ingress

Related Commands

Command	Description
clear mac-accounting (Ethernet)	Clears MAC accounting statistics for a specified interface.
show mac-accounting (Ethernet)	Displays MAC accounting statistics for a specified interface.

mac-address (Ethernet)

To set the MAC layer address of an Ethernet interface, use the mac-address command in interface configuration mode. To return the device to its default MAC address, use the no form of this command.

mac-address value1.value2.value3

no mac-address

Syntax Description

value1.	High 2 bytes of the MAC address in hexadecimal format. Range is from 0 to ffff.
value2.	Middle 2 bytes of the MAC address in hexadecimal. Range is from 0 to ffff.
value3	Low 2 bytes of the MAC address in hexadecimal. Range is from 0 to ffff.

Defaults

The default MAC address is read from the hardware burned-in address (BIA).

Command Modes

Interface configuration

Command History

Release	Modification
Release 2.0	This command was introduced on the Cisco CRS-1.
Release 3.0	No modification.
Release 3.2	No modification.
Release 3.3.0	No modification.
Release 3.4.0	No modification.
Release 3.5.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

The MAC address must be in the form of three 4-digit values (12 digits in dotted decimal notation).

The mac-address command is available for all types of line card Ethernet interfaces (Gigabit Ethernet, 10-Gigabit Ethernet, Fast Ethernet) and for the Management Ethernet interface.

Task ID

Task ID	Operations
interface	read, write

Examples

The following example shows how to set the MAC address of a Gigabit Ethernet interface located at 0/1/5/0:

RP/0/RP0/CPU0:router(config)# interface GigabitEthernet 0/1/5/0 

RP/0/RP0/CPU0:router(config-if)# mac-address 0001.2468.ABCD

negotiation auto

To enable link autonegotiation on Gigabit Ethernet and Fast Ethernet interfaces, use the negotiation auto command in interface configuration mode. To disable link autonegotiation, use the no form of this command.

negotiation auto

no negotiation auto

Syntax Description

This command has no arguments or keywords.

Defaults

Link autonegotiation is disabled.

Command Modes

Interface configuration

Command History

Release	Modification
Release 3.3.0	This command was introduced on the Cisco CRS-1 and the Cisco XR 12000 Series Router.
Release 3.4.0	No modification.
Release 3.5.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

The negotiation auto command is available on Gigabit Ethernet and Fast Ethernet interfaces only.

Task ID

Task ID	Operations
interface	read, write

Examples

The following example shows how to enable link autonegotiation on an interface:

RP/0/RP0/CPU0:router(config)# interface FastEthernet 0/0/2/0

RP/0/RP0/CPU0:router(config-if)# negotiation auto

The following example shows how to disable link autonegotiation on an interface:

RP/0/RP0/CPU0:router(config)# interface FastEthernet 0/0/2/0

RP/0/RP0/CPU0:router(config-if)# no negotiation auto

packet-gap non-standard

To change the packet interval for traffic on an interface for improved interoperability with
Cisco Catalyst 6000 series switches, use the packet-gap non-standard command in interface configuration mode. To use the standard packet interval as defined by the IEEE 802.ae specification, use the no form of this command.

packet-gap non-standard

no packet-gap non-standard

Syntax Description

This command has no arguments or keywords.

Defaults

The interface uses the standard packet interval as defined by the IEEE 802.ae specification.

Command Modes

Interface configuration

Command History

Release	Modification
Release 3.0	This command was first introduced on the Cisco CRS-1.
Release 3.2	This command was first supported on the Cisco XR 12000 Series Router.
Release 3.3.0	No modification.
Release 3.4.0	No modification.
Release 3.5.0	No modification.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.

An interface that is connected to a Cisco Catalyst 6000 series switch may experience packet loss problems that can be resolved by changing the packet interval of traffic from standard (as defined by the IEEE 802.ae specification) to nonstandard using the packet-gap non-standard command.

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Note The packet-gap non-standard command is available on 10-Gigabit Ethernet interfaces only.

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Task ID

Task ID	Operations
interface	read, write

Examples

The following example shows how to change the packet interval for traffic on an interface from standard to nonstandard:

RP/0/RP0/CPU0:router(config)# interface TenGigE 0/3/0/0

RP/0/RP0/CPU0:router(config-if)# packet-gap non-standard

show controllers (Ethernet)

To display status and configuration information about the Ethernet interfaces on a specific node, use the show controllers command in EXEC mode.

show controllers {GigabitEthernet | TenGigE | fastethernet} instance [all | bert | internal | mac | phy | stats | xgxs]

Syntax Description

{GigabitEthernet | TenGigE | fastethernet}	Indicates the type of Ethernet interface whose MAC accounting statistics you want to display. Enter GigabitEthernet, TenGigE, or fastethernet. Note Fast Ethernet interfaces are available only on the Cisco XR 12000 Series Router.
instance	(Optional) Specifies and Ethernet interface instance. The naming notation is rack/slot/module/port, and a slash between values is required as part of the notation. •rack—Chassis number of the rack. •slot—Physical slot number of the line card or modular services card. •module—Module number. A physical layer interface module (PLIM) is always 0. •port—Physical port number of the interface. The instance argument is entered in the rack/slot/module/port notation. Note For more information about the syntax for the router, use the question mark (?) online help function.
all	Displays detailed information for the specified interface.
bert	Displays BERT status information for the interface.
internal	Displays internal information for the interface.
mac	Displays mac information for the interface.
phy	Displays physical information for the interface.
stats