Netgear GSM7212P GSM5212P/GSM7212P/GSM7212F/GSM7224P CLI Manual - Page 305

ProSafe Managed Switch show ip ospf virtual-link brief This command displays the OSPF Virtual Interface information for all areas in the system. Format Modes show ip ospf virtual-link brief • Privileged EXEC • User EXEC Term Area ID Neighbor Hello Interval Dead Interval Retransmit Interval Transit Delay Definition The area id of the requested OSPF area. The neighbor interface of the OSPF virtual interface. The configured hello interval for the OSPF virtual interface. The configured dead interval for the OSPF virtual interface. The configured retransmit interval for the OSPF virtual interface. The configured transit delay for the OSPF virtual interface. OSPF Graceful Restart Commands The OSPF protocol can be configured to participate in the checkpointing service, so that these protocols can execute a graceful restart when the management unit fails. In a graceful restart, the hardware to continues forwarding IPv4 packets using OSPF routes, while a backup switch takes over management unit responsibility. Graceful restart uses the concept of "helpful neighbors." A fully adjacent router enters helper mode when it receives a link state announcement (LSA) from the restarting management unit indicating its intention of performing a graceful restart. In helper mode, a switch continues to advertise to the rest of the network that they have full adjacencies with the restarting router, thereby avoiding announcement of a topology change and the potential for flooding of LSAs and shortest-path-first (SPF) runs, which determine OSPF routes. Helpful neighbors continue to forward packets through the restarting router. The restarting router relearns the network topology from its helpful neighbors. Graceful restart can be enabled for planned or unplanned restarts, or both. A planned restart is initiated by the operator through the management command initiate failover. The operator may initiate a failover to take the management unit out of service (for example, to address a partial hardware failure), to correct faulty system behavior that cannot be corrected through less severe management actions, or other reasons. An unplanned restart is an unexpected failover, caused by a fatal hardware failure of the management unit or a software hang or crash on the management unit. Routing Commands 305