Implementing MPLS Traffic Engineering
Related Topics
Configuring Auto-Tunnel Mesh Tunnel ID, on page 323
Configuring Auto-tunnel Mesh Unused Timeout, on page 324
Configuring Auto-Tunnel Mesh Group, on page 326
Configuring Tunnel Attribute-Set Templates, on page 327
Enabling LDP on Auto-Tunnel Mesh, on page 330
Destination List (Prefix-List)
Auto-mesh tunnels can be automatically created using prefix-list. Each TE enabled router in the network
learns about the TE router IDs through a existing IGP extension.
You can view the router IDs on the router using this command:
show mpls traffic-eng topology | include TE Id
IGP Id: 0001.0000.0010.00, MPLS TE Id:100.1.1.1 Router Node
IGP Id: 0001.0000.0011.00, MPLS TE Id:100.2.2.2 Router Node
IGP Id: 0001.0000.0012.00, MPLS TE Id:100.3.3.3 Router Node
A prefix-list may be configured on each TE router to match a desired set of router IDs (MPLS TE ID as shown
in the above output). For example, if a prefix-list is configured to match addresses of 100.0.0.0 with wildcard
0.255.255.255, then all 100.x.x.x router IDs are included in the auto-mesh group.
When a new TE router is added in the network and its router ID is also in the block of addresses described
by the prefix-list, for example, 100.x.x.x, then it is added in the auto-mesh group on each existing TE router
without having to explicitly modify the prefix-list or perform any additional configuration.
Auto-mesh does not create tunnels to its own (local) TE router IDs.
When prefix-list configurations on all routers are not identical, it can result in non- symmetrical mesh of
Note
tunnels between those routers.
Related Topics
Configuring Auto-Tunnel Mesh Tunnel ID, on page 323
Configuring Auto-tunnel Mesh Unused Timeout, on page 324
Configuring Auto-Tunnel Mesh Group, on page 326
Configuring Tunnel Attribute-Set Templates, on page 327
Enabling LDP on Auto-Tunnel Mesh, on page 330
VRF Redirection to MPLS TE Tunnels
The VRF redirection to MPLS TE tunnels feature adds automatic route MPLS TE tunnels through autoroute
destination configuration. The VRF redirection to MPLS TE tunnels maps VRF prefixes over TE tunnels in
the core to reach the same egress provider edge (PE). This enables to load-balance prefix traffic on multiple
tunnels based on equal cost multi-path (ECMP). The ECMP is used to load-share the flow(s) on multiple
available paths towards the destination PE. The route added by autoroute destination inherits the same IGP
Cisco IOS XR MPLS Configuration Guide for the Cisco CRS Router, Release 5.1.x
Destination List (Prefix-List)
(ISIS 1 level-2)
(ISIS 1 level-2)
(ISIS 1 level-2)
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