Configuring Graceful Restart for VPNs

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;}

To configure graceful restart globally, include the graceful-restart statement at the following hierarchy levels:

[edit routing-options]
[edit logical-systems logical-system-name routing-options]

To configure in graceful restart in a particular routing instance, include the graceful-restart statement at the following hierarchy levels:

[edit routing-instances routing-instance-name routing-options]
[edit logical-systems logical-system-name routing-instances routing-instance-name routing-options]

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.

You can include the restart-duration option at either the global or routing instance level. The routing instance value overrides the global value if both are configured.