Dell PowerConnect 6248 User's Guide - Page 669

Displaying OSPFv3 Route Redistribution Summary Using CLI Commands For information about the CLI commands that perform this function, see the following chapter in the CLI Reference Guide: • OSPFv3 Commands The following table summarizes the equivalent CLI commands for this feature. Table 10-25. OSPFv3 Route Redistribution Summary Command CLI Command show ipv6 ospf Description Displays OSPFv3 route redistribution summary data. Nonstop Forwarding OSPFv3 Graceful Restart The OSPFv3 protocol can be configured to perform a "graceful restart" in conjunction with the nonstop forwarding feature (see "Nonstop Forwarding" on page 258) for stacked switches. When OSPFv3 graceful restart is enabled and the management unit in a stack fails, the hardware can continue to forward packets using OSPFv3 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 and the potential for flooding of LSAs and shortest-parth-first (SPF) runs (which determine OSPFv3 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 either planned or unplanned restarts, or both. A planned restart is initiated by the operator (see "Enabling and Disabling NSF" on page 258). The operator may initiate a failover in order to take the management unit out of service (for example, to address a partial hardware failure), to correct faulty system behavior which 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. To configure the OSPFv3 graceful restart feature, click IPv6 →OSPFv3 →NSF OSPFv3 Summary in the navigation tree. Configuring IPv6 669