Technical Documentation

Option: GMPLS Graceful Restart

GMPLS supports graceful restart, a mechanism that allows a restarting router to continue forwarding packets to neighbors without interruption. The restarting router relies on its forwarding table temporarily while it receives updates from “helper” neighbors that assist the restarting router in rebuilding its routing table.

To enable graceful restart for all routing protocols including GMPLS, include the graceful-restart statement at the [edit routing-options] hierarchy level. To disable graceful restart for GMPLS and RSVP, include the disable statement at the [edit protocols rsvp graceful-restart] hierarchy level. To disable GMPLS and RSVP graceful restart helper capability, include the helper-disable statement at the [edit protocols rsvp graceful-restart] hierarchy level.

To configure the maximum amount of time the routing platform retains information for restarting neighbors, include the maximum-helper-recovery-time statement at the [edit protocols rsvp graceful-restart] hierarchy level. The default helper recovery time is 180 seconds, with a minimum value of 1 second and a maximum value of 3600 seconds. To view the current value configured for the helper recovery time, issue the show rsvp version operational mode command.

To configure the maximum amount of time the routing platform waits until a neighbor is declared dead, include the maximum-helper-restart-time statement at the [edit protocols rsvp graceful-restart] hierarchy level. The default helper restart time is 20 seconds, with a minimum value of 1 second and a maximum value of 1800 seconds. To view the current value configured for the helper restart time, issue the show rsvp version operational command.

[edit]protocols {rsvp {graceful-restart {disable;helper-disable;maximum-helper-recovery-time seconds;maximum-helper-restart-time seconds;}}}

For more information about graceful restart, see the JUNOS High Availability Configuration Guide.


Published: 2010-04-15