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

Preferred tunnel path

Updated: June 15, 2026

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Introduces preferred tunnel path concepts, highlighting key benefits, deployment restrictions, and step-by-step configuration for MPLS-TE tunnels and VPLS integration to ensure optimal Layer 2 forwarding, including end-to-end service setup.

Preferred tunnel path is a configuration mechanism that

influences transport path selection for Layer 2 service traffic
maps pseudowires to specific traffic engineering tunnels, and
targets network traffic paths through specific tunnels.

Feature history

The feature history table lists release support for this feature.

Table 1. Feature History Table
Feature Name	Release Information	Feature Description
VPLS over preferred TE and MPLS OAM	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.
VPLS over preferred TE and MPLS OAM	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
VPLS over preferred TE and MPLS OAM	Release 25.1.1	Introduced in this release on: Fixed Systems (8010 [ASIC: A100])(select variants only) The VPLS over preferred TE and MPLS OAM feature with MPLS OAM capabilities helps you troubleshoot MPLS networks. This feature is now supported on the Cisco 8011-4G24Y4H-I routers.
VPLS over preferred TE and MPLS OAM	Release 24.4.1	Introduced in this release on: Fixed Systems (8700 [ASIC: K100])(select variants only*) VPLS over preferred TE and MPLS OAM is now supported on the Cisco 8712-MOD-M routers.
VPLS over preferred TE and MPLS OAM	Release 24.3.1	Introduced in this release on: Fixed Systems (8700 [ASIC: P100 ])(select variants only) The VPLS over preferred TE and MPLS OAM feature with MPLS OAM capabilities helps you troubleshoot MPLS networks. This feature is now supported on: 8711-32FH 88-LC1-52Y8H-EM 88-LC1-12TH24FH-E
VPLS over preferred TE and MPLS OAM	Release 24.2.1	Introduced in this release on: Fixed Systems (8200 [ASIC: P100])(select variants only) This feature which uses MPLS OAM capabilities to troubleshoot MPLS networks is now supported on the Cisco 8212-48FH-M routers.
VPLS over preferred TE and MPLS OAM	Release 24.1.1	Introduced in this release on: Modular Systems (8800 [LC ASIC: P100])(select variants only) This feature which uses MPLS OAM capabilities to troubleshoot MPLS networks is now supported on the Cisco 88-LC1-36EH line cards.
VPLS over preferred TE and MPLS OAM	Release 7.5.2	Based on your network traffic pattern, you can configure the preferred Traffic Engineering (TE) tunnel path between Provider Edge (PE) routers participating in the same Virtual Private LAN Services (VPLS). You optimize network resource utilization and performance when you set an explicit path on the PE router to direct traffic flow to a specific destination PE router. With VPLS, you now have MPLS-OAM capabilities for troubleshooting MPLS networks: MPLS LSP Ping MPLS LSP Traceroute Flow-Aware Transport (FAT) Pseudowires (PW) This functionality adds the following command: control-word

Preferred tunnel path benefits

Mapping VPLS pseudowires to explicit, preferred traffic engineering tunnel paths on a PE router offers key operational advantages for MPLS networks:

Optimizes network resource utilization and performance by directing traffic flows to specific destination PE routers using explicit path configuration.
Supports fallback enable options to maintain service continuity when the preferred tunnel path is unavailable.
Enables efficient troubleshooting in MPLS networks by leveraging MPLS Operations, Administration, and Maintenance (OAM) capabilities.

Preferred tunnel path restrictions

If you plan or configure a preferred tunnel path, ensure the following requirement:

The preferred tunnel path configuration applies only to MPLS encapsulation.

Configure preferred tunnel path

Specify a preferred MPLS tunnel for a pseudowire, ensuring traffic uses the designated path and disables fallback alternatives.

Use this task to define a preferred MPLS Traffic Engineering (TE) tunnel for a pseudowire. When configured, the pseudowire directs traffic through the specified tunnel interface and prevents traffic from using alternate routes if the preferred tunnel is unavailable.

Before you begin

Confirm that MPLS encapsulation is enabled.
Verify that the required tunnel interface exists and is operational.

Follow these steps to configure a preferred tunnel path for a pseudowire:

Procedure

	1.	Enter global configuration mode. Example: `Router# configure` Enters the global configuration mode.
	2.	Enter L2VPN configuration mode. Example: `Router(config)# l2vpn` Enters the L2VPN configuration mode.
	3.	Define the pseudowire class to configure tunnel preference. Example: `Router(config-l2vpn)# pw-class PATH1` Defines the pseudowire class, PATH1, to configure tunnel preferences.
	4.	Specify MPLS as the encapsulation type for the pseudowire. Example: `Router(config-l2vpn-pwc)# encapsulation mpls` Specifies MPLS as the encapsulation type for the pseudowire.
	5.	Set the preferred tunnel interface and disable fallback options. Example: `Router(config-l2vpn-pwc-mpls)# preferred-path interface tunnel-te1 fallback disable` Here, interfacetunnel-te1 specifies the preferred MPLS TE tunnel and fallback disable prevents using alternate paths if the preferred tunnel is unavailable.
	6.	Commit and save the configuration. Example: `Router(config-l2vpn-pwc-mpls)# commit` Saves and applies the configuration changes.

Configure MPLS-TE tunnel for VPLS

Set up an MPLS-TE tunnel to ensure a preferred and optimized path for VPLS traffic across the network.

This task outlines the CLI commands required to configure an MPLS-TE tunnel for VPLS. The tunnel enables traffic engineering by directing VPLS packets through a specified path, improving network reliability and control.

Before you begin

Confirm that MPLS traffic engineering is enabled.
Ensure routing and interface addressing are planned.
Identify the tunnel interface name and destination IP address.

Follow these steps to configure an MPLS-TE tunnel for VPLS:

Procedure

	1.	Enter the tunnel interface configuration mode. Example: `Router(config)# interface tunnel-te1` Enters the configuration mode for the MPLS-TE tunnel interface.
	2.	Set the tunnel to use an IPv4 unnumbered loopback interface. Example: `Router(config-if)# ipv4 unnumbered Loopback0` Sets the tunnel to use an IPv4 unnumbered loopback interface.
	3.	Specify the signaled bandwidth for the tunnel. Example: `Router(config-if)# signalled-bandwidth 50` Specifies the signaled bandwidth for the tunnel.
	4.	Define the tunnel destination IP address. Example: `Router(config-if)# destination 10.12.12.12` Defines the destination IP address for the tunnel.
	5.	Specify the explicit path option for the tunnel. Example: `Router(config-if)# path-option 1 explicit name FC1` Specifies the explicit path option.
	6.	Save and apply configuration changes. Example: `Router(config)# commit` Saves and applies the configuration changes.

Configure VPLS over preferred TE tunnel

Assign a preferred MPLS-TE tunnel to carry VPLS service traffic, optimizing network redundancy and performance.

You perform this task to ensure VPLS traffic follows a specified traffic engineering tunnel, supporting redundancy and traffic optimization in a service provider environment.

Before you begin

Confirm that an MPLS-TE tunnel is configured and available.
Ensure that your VPLS bridge-domain design is complete and meets service requirements.

Follow these steps to configure VPLS over a preferred TE tunnel:

Procedure

	1.	Define the Layer 2, specify the VLAN encapsulation for the interface, and configure ingress tag rewrite for VLAN. Example: `Router# configure Router(config)# interface FourHundredGigE0/0/0/0.1 l2transport Router(config-subif)# encapsulation dot1q 100 Router(config-subif)# rewrite ingress tag pop 1 symmetric`
	2.	Exit subinterface configuration mode. Example: `Router(config-subif)# exit`
	3.	Create pseudowire class for the VPLS pseudowire and specify MPLS encapsulation for the pseudowire. Example: `Router(config)# l2vpn Router(config-l2vpn)# pw-class c Router(config-l2vpn-pwc)# encapsulation mpls`
	4.	Enable the control word and flow-label-based load balancing for the pseudowire. Example: `Router(config-l2vpn-pwc-mpls)# control-word Router(config-l2vpn-pwc-mpls)# load-balancing Router(config-l2vpn-pwc-mpls-load-bal)# flow-label both`
	5.	Specify the preferred MPLS-TE tunnel path for the pseudowire. Example: `Router(config-l2vpn-pwc-mpls)# preferred-path interface tunnel-te1`
	6.	Exit pseudowire class configuration mode. Example: `Router(config-l2vpn-pwc-mpls)# exit Router(config-l2vpn-pwc)# exit`
	7.	Define the VPLS bridge group and bridge domain, associate the access interface with the bridge domain. Example: `Router(config-l2vpn)# bridge group bg bridge-domain bd Router(config-l2vpn-bg-bd)# interface FourHundredGigE0/0/0/0.1 Router(config-l2vpn-bg-bd-ac)# exit`
	8.	Define a pseudowire neighbor for the bridge domain and associate the pseudowire class with the neighbor pseudowire. Example: `Router(config-l2vpn-bg-bd)# neighbor 10.12.12.12 pw-id 100 Router(config-l2vpn-bg-bd-pw)# pw-class c`
	9.	Verify the VPLS over preferred TE tunnel configuration. Example: Router(PE1)# show l2vpn xconnect group XCON_1 Legend: ST = State, UP = Up, DN = Down, AD = Admin Down, UR = Unresolved, SB = Standby, SR = Standby Ready, (PP) = Partially Programmed XConnect Segment 1 Segment 2 Group Name ST Description ST Description ST ------------------------ ----------------------------- ----------------------------- XCON_1 XCON1_P2P2 UP Hu0/1/0/0.1 UP 172.16.0.1 1000 UP Backup 192.168.0.1 1000 SB ----------------------------------------------------------------------------------- Router(PE2)# show l2vpn xconnect group XCON_1 Tue Jan 17 15:36:12.327 UTC Legend: ST = State, UP = Up, DN = Down, AD = Admin Down, UR = Unresolved, SB = Standby, SR = Standby Ready, (PP) = Partially Programmed XConnect Segment 1 Segment 2 Group Name ST Description ST Description ST ------------------------ ----------------------------- ----------------------------- XCON_1 XCON1_P2P2 UP BE100.1 UP 10.0.0.1 1000 UP ---------------------------------------------------------------------------------------- Router(PE3)# show l2vpn xconnect group XCON_1 Tue Jan 17 15:38:04.785 UTC Legend: ST = State, UP = Up, DN = Down, AD = Admin Down, UR = Unresolved, SB = Standby, SR = Standby Ready, (PP) = Partially Programmed XConnect Segment 1 Segment 2 Group Name ST Description ST Description ST ------------------------ ----------------------------- ----------------------------- XCON_1 XCON1_P2P2 DN BE100.1 UP 10.0.0.1 1000 SB ---------------------------------------------------------------------------------------- Router# show l2vpn xconnect summary Number of groups: 3950 Number of xconnects: 3950 Up: 3950 Down: 0 Unresolved: 0 Partially-programmed: 0 AC-PW: 3950 AC-AC: 0 PW-PW: 0 Monitor-Session-PW: 0 Number of Admin Down segments: 0 Number of MP2MP xconnects: 0 Up 0 Down 0 Advertised: 0 Non-Advertised: 0 Number of CE Connections: 0 Advertised: 0 Non-Advertised: 0 Backup PW: Configured : 3950 UP : 0 Down : 0 Admin Down : 0 Unresolved : 0 Standby : 3950 Standby Ready: 0 Backup Interface: Configured : 0 UP : 0 Down : 0 Admin Down : 0 Unresolved : 0 Standby : 0

VPLS service traffic is routed via the preferred MPLS-TE tunnel. The configuration changes are committed, and verification output confirms the expected state.

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Preferred tunnel path

Feature history

Preferred tunnel path benefits

Preferred tunnel path restrictions

Configure preferred tunnel path

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Configure MPLS-TE tunnel for VPLS

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Configure VPLS over preferred TE tunnel

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