The path selection revert timer provides an option to stabilize a path before traffic is switched to it. Without a configured path selection revert timer, the router switches between a primary and secondary path immediately after the current working path goes down.
There is no revert-timer in the default command mode.
The number of seconds that the router waits after the primary or selected path comes up before traffic reverts to that path. The range is 1- 65,535 seconds.
MPLS LSP configuration mode (config-router-mpls-lsp-lsp_name).
The revert-timer command has no effect on the unconditional select mode. Traffic is unconditionally switched to the user selected path and stays on it.
The path stability test used with the revert timer is based on the uptime of the latest instance of the path. This value can be different when the selected path has gone through a "make-before-break" procedure.
For an LSP going through re-optimization, the new LSP does not carry traffic until the revert timer expires.
When a user changes the revert timer, the basis of counting is the uptime of the path and is independent of the sequence or combination of configurations.
The no form of the command removes the revert-timer.
MPLS is supported on the Extreme 8820, SLX 9740, SLX 9640, and SLX 9540 devices only.
The following example configures the revert-timer to 10 seconds.
device# configure device(config)# router mpls device(config-router-mpls)# lsp samplelsp device(config-router-mpls-lsp-samplelsp)# revert-timer 10