Cisco Systems A9014CFD manual Fast Reroute, Link Protection, 34-4

Chapter 34 MPLS Traffic Engineering - Fast Reroute Link Protection

How to Configure Traffic Engineering - Fast Reroute Link Protection

BFD

BFD is a detection protocol designed to provide fast forwarding link failure detection times for all media types, encapsulations, topologies, and routing protocols. In addition to fast forwarding link failure detection, BFD provides a consistent failure detection method for network administrators. Because the network administrator can use BFD to detect forwarding link failures at a uniform rate, rather than the variable rates for different routing protocol Hello mechanisms, network profiling and planning is easier, and reconvergence time is consistent and predictable.

Fast Reroute

Fast Reroute is a mechanism for protecting MPLS TE LSPs from link failures by locally repairing the LSPs at the point of failure. This allows the data to continue to flow on them while their headend routers attempt to establish new end-to-end LSPs to replace them. FRR locally repairs the protected LSPs by rerouting them over backup tunnels that bypass failed links.

Link Protection

Backup tunnels that bypass only a single link of the LSP’s path provide link protection. They protect LSPs if a link along their path fails by rerouting the LSP’s traffic to the next hop (bypassing the failed link). These are referred to as next-hop (NHOP) backup tunnels because they terminate at the LSP’s next hop beyond the point of failure.

How to Configure Traffic Engineering - Fast Reroute Link Protection

This section describes how to configure MPLS TE-FRR Link Protection feature:

•Enabling MPLS TE-FRR on an SVI Interface, page 34-5(Required)

•Enabling MPLS TE-FRR for EoMPLS on a Global Interface, page 34-5(Required)

•Enabling MPLS TE-FRR for EoMPLS on an Interface, page 34-7(Required)

•Enabling MPLS TE-FRR for IS-IS, page 34-9(Required)

•Configuring Primary One-hopAuto-Tunnels, page 34-11(Required)

•Configuring Backup Auto-Tunnels, page 34-13(Required)

•Enabling Targeted LDP session over Primary one-hopAuto-Tunnels, page 34-14(Required)

•Enabling BFD Triggered FRR on an SVI Interface, page 34-15(Required)

•Enabling BFD Triggered FRR on a Router, page 34-16(Required)

•Verifying MPLS TE-FRR Configuration, page 34-17(Optional)

•Verifying Primary One-hopAuto-Tunnels, page 34-19(Optional)

•Verifying Backup Auto-Tunnels, page 34-19(Optional)

•Verifying BFD Triggered FRR Configuration, page 34-20(Optional)

	Cisco ASR 901 Series Aggregation Services Router Software Configuration Guide
34-4	OL-23826-09