Configuring an Adaptive LSP

The Fusion software supports adaptive LSPs. When configuring an adaptive LSP, the user can change the following parameters of an LSP while it is in the enabled state:

  • CSPF
  • exclude-any
  • hop-limit
  • include-all
  • include-any
  • primary-path
  • priority
  • tie-breaking
  • traffic-eng

When one of these parameters is changed on a Adaptive LSP, a new instance of the same LSP is signaled using the newly defined parameters. Once the new LSP comes up, traffic is moved to the new LSP instance and the old LSP instance is torn down.

To configure an LSP named to20 as an adaptive LSP, complete the following steps.

  1. Configure the device
    device# configure
  2. Enable the MPLS router.
    device(config)# router mpls
  3. Configure the signaled label switched path (LSP).
    device(config-router-mpls)# lsp to20
    In this example, the LSP name is to20 .
  4. Enable the LSP to be modified without exiting.
    device(config-router-mpls-lsp-to20)# adaptive

The following example configures an LSP named to20 as an adaptive LSP.

device# configure
device(config)# router mpls
device(config-router-mpls)# lsp to20
device(config-router-mpls-lsp-to20)# adaptive

Once an LSP is configured to be adaptive, it can have the parameters described above changed. In the following example, the setup and hold priorities for adaptive lsp to20 are changed to seven and one.

device(config-router-mpls)# lsp to20
device(config-router-mpls-lsp-to20)# priority 7 1

The new parameters are not changed for the adaptive LSP until the commit command is issued for the LSP.

Note

Note

Once the commit command has been issued, there may be a 30 millisecond traffic disruption.

In the following example of the show mpls lsp command for lsp to20 , the priorities are not changed in the output.

device(config-router-mpls-lsp-to212)# show mpls lsp to212
LSP to212, to 10.5.1.1
 From: 10.4.1.1, admin: UP, status: UP, tunnel interface: tnl1
  Times primary LSP goes up since enabled: 1
  Metric: 0, number of installed aliases: 0 Adaptive
  Maximum retries: 0, no. of retries: 0
  Setup priority: 7, hold priority: 0
  Max rate: 0 kbps, mean rate: 0 kbps, max burst: 0 bytes
  Constraint-based routing enabled: yes
  Tie breaking: random, hop limit: 0
  OTHER INSTANCE PRIMARY: NEW_INSTANCE admin: DOWN, status: DOWN
  Maximum retries: 0, no. of retries: 0
  Setup priority: 7, hold priority: 1
  Max rate: 0 kbps, mean rate: 0 kbps, max burst: 0 bytes
  Constraint-based routing enabled: yes
  Tie breaking: random, hop limit: 0
  Active Path attributes:
  Tunnel interface: tnl1, outbound interface: e0/2
  Tunnel index: 4, Tunnel instance: 1 outbound label: 3
  Path calculated using constraint-based routing: yes
  Explicit path hop count: 1
    10.2.1.2 (S)
  Recorded routes:
   Protection codes: P: Local N: Node B: Bandwidth I: InUse
   10.2.1.2

The following commit command makes the new parameter settings active in the adaptive lsp to20 configuration.

device(config-router-mpls)# lsp to20
device(config-router-mpls-lsp-to20)# commit

After the commit command runs, the user can see that the priorities have changed by using the show mpls lsp command for lsp to20 .

device(config-router-mpls-lsp-to212)# show mpls lsp to212
LSP to212, to 10.5.1.1
 From: 10.4.1.1, admin: UP, status: UP, tunnel interface: tnl1
 Times primary LSP goes up since enabled: 1
 Metric: 0, number of installed aliases: 0 Adaptive
 Maximum retries: 0, no. of retries: 0
 Setup priority: 7, hold priority: 1
 Max rate: 0 kbps, mean rate: 0 kbps, max burst: 0 bytes
 Constraint-based routing enabled: yes
 Tie breaking: random, hop limit: 0
 Active Path attributes:
  Tunnel interface: tnl1, outbound interface: e0/2
  Tunnel index: 4, Tunnel instance: 2 outbound label: 3
  Path calculated using constraint-based routing: yes
  Explicit path hop count: 1
   10.2.1.2 (S)
  Recorded routes:
   Protection codes: P: Local N: Node B: Bandwidth I: InUse
   10.2.1.2