Graceful restart allows a router whose VPN control plane is undergoing a restart to continue to forward traffic while recovering its state from neighboring routers. Without graceful restart, a control plane restart disrupts any VPN services provided by the router. Graceful restart is supported on Layer 2 VPNs, Layer 3 VPNs, virtual-router routing instances, and VPLS.
To enable VPN graceful restart, include the graceful-restart statement:
-
graceful-restart {
- disable;
- restart-duration time-limit;
- }
You can configure the restart-duration option at either the global or routing instance level. The routing instance value overrides the global value if both are configured.
To configure the graceful-restart statement globally, include it at the following hierarchy levels:
To configure the graceful-restart statement in the routing instance configuration, include it at the following hierarchy levels:
The restart-duration option sets the period of time that the router waits for a graceful restart to be completed. You can configure a time between 1 through 600 seconds. The default value is 300 seconds. At the end of the configured time period, the router performs a standard restart without recovering its state from the neighboring routers. This disrupts VPN services, but is probably necessary if the router is not functioning normally.