Configure IPv6 IS-IS GR

GR (Graceful Restart) is used to keep the route information of the forwarding layer between the local device and the neighbor device unchanged during the active/standby switchover of the devices and the forwarding is not affected. After switching the device and running again, the protocol layer of the two devices synchronizes the route information and updates the forwarding layer so that the data forwarding is not interrupted during the device switchover.

There are two roles during GR:

• GR Restarter: The device performing the protocol graceful restarting
• GR Helper: The device assisting the protocol graceful restarting

The distributed device can serve as GR Restarter and GR Helper, while the centralized device can only serve as GR Helper, assisting Restarter to complete GR.

Configuration Condition

Before configuring the IPv6 IS-IS GR, first complete the following tasks:

• Configure the IPv6 address of the interface to enable the neighboring nodes to be reachable at the network layer.
• Enable the IPV6 IS-IS protocol.

Configure IPv6 IS-IS GR Helper

GR Helper helps Restarter to complete GR. By default, the device enables the function, and the user can disable the function via the command.

Table 10-35 Configure IS-IS GR helper