Nonstop Forwarding Ospfv3 Graceful Restart - Dell PowerConnect 6224 User Manual

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

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.
Description
Displays OSPFv3 route redistribution summary data.
669
Configuring IPv6