Cisco Cisco IOS Software Release 12.0(13)S7

Perform the following task to set router behavior when no record of MPLS label usage exists. 

The default behavior in this situation is for the router to proceed as if all MPLS labels were in use before 
the router restarts. This means that no MPLS labels are available after the restart until a safe-to-reuse 
timer expires. 

If you change the state of all MPLS labels to the free state, all labels are available immediately after the 
restart, but you risk temporarily unsafe label reuse. Packets meant for one destination might be 
forwarded to a different destination temporarily. You might configure the router to consider all MPLS 
labels to be in the free state when the router finds no label usage record if:

You judge that the risk of restarting without regard to previous label usage is acceptable the few 
times MPLS pdata might not be available.

Your network is not at risk for incorrectly forwarded packets due to the premature reuse of labels 
following a restart.

You require more MPLS labels be available immediately following a router restart than the MPLS 
Safe Label Reuse After Router Restart feature permits.

Router> enable

Enables privileged EXEC mode. 

Enter your password if prompted.

 terminal

Router# configure terminal

Enters global configuration mode.

Router(config)# mpls label restart

Enters mpls-label-restart configuration mode to configure 
parameter settings that govern MPLS label usage following 
a router restart.

Router(mpls-label-restart)# pdata absent 

timeout 180

Sets the MPLS label reuse timeout value when the router 
does not find persistent data that describes MPLS label 
usage.

The seconds argument is the timeout value in seconds. 

This is the time from router restart that must elapse 
before the MPLS labels are available for label 
allocation. This ensures safe MPLS label reuse after a 
router startup when no persistent data is found.

Router(mpls-label-restart)# end

Exits to privileged EXEC mode.