Configuring MPLS fast reroute using one-to-one backup

To configure MPLS fast reroute by using the one-to-one backup method for a defined LSP, complete the following steps.

  1. Enable the device for configuration.
    device# configure
  2. Enable the MPLS router.
    device(config)# router mpls 
  3. Configure the LSP.
    device(config-router-mpls)# lsp frr_tunnel
    In this example, the specified LSPs name is frr_tunnel.
  4. Configure the egress router of the LSP.
    device(config-router-mpls-lsp-frr_tunnel)# to 10.1.1.1
    In this example, the egress router IP address of the LSP is 10.1.1.1.
  5. Configure the primary path.
    device(config-router-mpls-lsp-frr_tunnel)# primary-path direct_path
    In this example, the primary paths name is direct_path.
  6. Configure the secondary path.
    device(config-router-mpls-lsp-frr_tunnel)# secondary-path alt_path
    In this example, the secondary paths name is alt_path.
  7. Enable configuration of fast reroute options.
    device(config-router-mpls-lsp-frr_tunnel)# frr
  8. Configure bandwidth for the backup LSP.
    device(config-router-mpls-lsp-frr-tunnel_frr)# bandwidth 100
    In this example, the bandwidth is configured to 100 kbits/sec.
  9. Configure the number of hops the backup LSP can traverse (from PLR to MP).
    device(config-router-mpls-lsp-frr-tunnel_frr)# hop-limit 20
    In this example, the hop limit is configure a maximum of 20.

In the following example, MPLS Fast Reroute is configured by using the one-to-one backup method for a defined LSP named frr_tunnel .

device# configure 
device(config)# router mpls
device(config-router-mpls)# lsp frr_tunnel
device(config-router-mpls-lsp-frr_tunnel)# to 10.1.1.1
device(config-router-mpls-lsp-frr_tunnel)# primary-path direct_path
device(config-router-mpls-lsp-frr_tunnel)# secondary-path alt_path
device(config-router-mpls-lsp-frr_tunnel)# frr
device(config-router-mpls-lsp-frr_tunnel-frr)# bandwidth 100
device(config-router-mpls-lsp-frr_tunnel-frr)# hop-limit 20

Th frr command enables MPLS Fast Reroute using the one-to-one backup on the LSP under whose configuration it is enabled.