L2VPN Configuration Guide for Cisco 8000 Series Routers, Cisco IOS XR Releases

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L2VPN Configuration Guide for Cisco 8000 Series Routers, Cisco IOS XR Releases

Local switching between attachment circuits

Updated: June 15, 2026

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Details local switching between attachment circuits by introducing the concept and providing configuration procedures for enabling seamless traffic forwarding within a single device.

A local switching connection between attachment circuits is a point-to-point Layer 2 service that

  • exchanges Layer 2 data from one attachment circuit to another on the same device

  • operates like a bridge domain that has only two bridge ports, and

  • forwards traffic from one port of the local connection to the other port.

Feature history

Table 1. Feature History Table

Feature Name

Release Information

Feature Description

Support of Tagged or Untagged VLAN on Physical and Bundle AC with VLAN Rewrite

Release 26.2.1

Introduced in this release on: Modular Systems (8800 [LC ASIC: K100])(select variants only*);

*This feature is supported on Cisco 88-LC1-48Y8H-EM line cards.

Support of Tagged or Untagged VLAN on Physical and Bundle AC with VLAN Rewrite

Release 25.4.1

Introduced in this release on: Fixed Systems (8010 [ASIC: A100])(select variants only*)

This feature is supported on:

  • 8011-32Y8L2H2FH

  • 8011-12G12X4Y-A/D

Support of Tagged or Untagged VLAN on Physical and Bundle AC with VLAN Rewrite

Release 25.1.1

Introduced in this release on: Fixed Systems (8700 [ASIC: K100], 8010 [ASIC: A100])(select variants only*)

*This feature is supported on:

  • 8011-4G24Y4H-I

  • 8712-MOD-M

Support of Tagged or Untagged VLAN on Physical and Bundle AC with VLAN Rewrite

Release 24.4.1

Introduced in this release on: Fixed Systems (8200 [ASIC: P100], 8700 [ASIC: P100])(select variants only*); Modular Systems (8800 [LC ASIC: P100])(select variants only*)

*This feature is supported on:

  • 8212-48FH-M

  • 8711-32FH-M

  • 88-LC1-36EH

  • 88-LC1-12TH24FH-E

  • 88-LC1-52Y8H-EM

Support of Tagged or Untagged VLAN on Physical and Bundle AC with VLAN Rewrite

Release 7.3.15

This feature supports tagged or untagged VLAN on physical and bundle interfaces. The tagged VLAN allows you to send and receive the traffic for multiple VLANs whereas the untagged VLAN allows you to send and receive the traffic for a single VLAN. The multiple VLANs are used to differentiate traffic streams so that the traffic can be split across different services.

Layer 2 local switching characteristics

Figure 1. Local switching between attachment circuits

Layer 2 local switching connections have these characteristics:

  • Because there is no bridging in a local connection, there is neither MAC learning nor flooding.

  • Attachment circuits in a local connection are not in the UP state if the interface state is DOWN.

  • Local switching attachment circuits use Layer 2 trunk main interfaces, bundle interfaces, and Ethernet Flow Points.

  • Same-port local switching allows Layer 2 data switching between two circuits on the same interface.

Configure local switching between attachment circuits

Use this task to configure point-to-point cross-connect between attachment circuits.

This task creates Layer 2 interfaces, establishes a point-to-point connection, and attaches the Layer 2 interfaces to the connection for local switching.

  • Create Layer 2 interfaces.

  • Create a cross-connect group and point-to-point connection.

  • Attach the Layer 2 interfaces to the point-to-point connection.

Procedure

1.

Configure Layer 2 transport and encapsulation on the VLAN subinterfaces.

Example:

Router# configure
Router(config)# interface HunGigE 0/0/0/1.1 l2transport
Router(config-subif)# encapsulation dot1q 5
Router(config-subif)# exit
Router(config)# interface HunGigE 0/0/0/9.1 l2transport
Router(config-subif)# encapsulation dot1q 5
Router(config-subif)# commit
2.

Configure local switching on the VLAN subinterfaces.

Example:

Router(config)# l2vpn
Router(config-l2vpn-xc)# p2p XCON1_P2P1
Router(config-l2vpn-xc-p2p)# interface HunGigE0/0/0/1.1
Router(config-l2vpn-xc-p2p)# interface HunGigE0/0/0/9.1
Router(config-l2vpn-xc-p2p)# commit
Router(config-l2vpn-xc-p2p)# exit
3.

Review the local switching running configuration.

Example:

configure

interface HunGigE 0/0/0/1.1 l2transport
 encapsulation dot1q 5
!
interface HunGigE 0/0/0/9.1 l2transport
  encapsulation dot1q 5
 !

l2vpn
   p2p XCON1_P2P1
    interface HunGigE0/0/0/1.1
    interface HunGigE0/0/0/9.1
    !
   !
 !
4.

Use the show l2vpn xconnect brief command to verify that the configured cross-connect is up.

Example:

router# show l2vpn xconnect brief

Locally Switching

  Like-to-Like                        UP       DOWN        UNR

    EFP                                1          0          0

    Total                              1          0          0


  Total                                1          0          0

Total: 1 UP, 0 DOWN, 0 UNRESOLVED

The local switching cross-connect is configured successfully, and verification output shows one locally switched EFP in the UP state.