Dell EMC SmartFabric OS10 User Guide Release 10.5.0

Graceful restart

When a networking device restarts, the adjacent neighbors and peers detect the condition. During a graceful restart, the restarting device and neighbors continue to forward the packets without interrupting network performance. The neighbors that help in the restart process are called helper routers.

When you enable graceful restart, the restarting device retains the routes learned by OSPF in the forwarding table. To re-establish OSPF adjacencies with neighbors, the restart OSPF process sends a grace LSA to all neighbors. In response, the helper router enters Helper mode and sends an acknowledgement back to the restarting device.

OS10 supports graceful restart Helper mode. Use the graceful-restart role helper-only command to enable Helper mode in ROUTER OSPF mode.

OS10(config)# router ospf 10
OS10(conf-router-ospf-10)# graceful-restart role helper-only

Use the no version of the command to disable Helper mode.