Dell Force10 Z9000 FTOS Configuration Guide for Z9000 System - Page 629

• Helper role in which the router's graceful restart function is to help a restarting neighbor router in its graceful restarts. • Helper-reject role in which OSPF does not participate in the graceful restart of a neighbor. OSPFv2 supports "helper-only" and "restarting-only" roles. By default, both helper and restarting roles are enabled. OSPFv2 supports the helper-reject role globally on a router. OSPFv3 supports "helper-only" and "restarting-only" roles. The "helper-only" role is enabled by default. To enable the restarting role in addition to the "helper-only" role, you must configure a grace period. You reconfigure OSPFv3 graceful restart to a "restarting-only" role when you enable the helper-reject role on an interface. OSPFv3 supports the helper-reject role on a per-interface basis. Configuring helper-reject role on an OSPFv2 router or OSPFv3 interface enables the restarting-only role globally on the router or locally on the interface. In a helper-reject role, OSPF does not participate in the graceful restart of an adjacent OSPFv2/v3 router. If multiple OSPF interfaces provide communication between two routers, after you configure helper-reject on one interface, all other interfaces between the two routers behave as if they are in the help-reject role. • OSPFv2 and OSPFv3 support planned-only and/or unplanned-only restarts. The default is support for both planned and unplanned restarts. A planned restart occurs when you enter the redundancy force-failover rpm command to force the primary RPM to switch to the backup RPM. During a planned restart, OSPF sends out a Grace LSA before the system switches over to the backup RPM. An unplanned restart occurs when an unplanned event causes the active RPM to switch to the backup RPM, such as when an active process crashes, the active RPM is removed, or a power failure happens. During an unplanned restart, OSPF sends out a Grace LSA when the backup RPM comes online. To display the configuration values for OSPF graceful restart, enter the following commands: • For OSPFv2: show run ospf • For OSPFv3: show run ospf and show ipv6 ospf database database-summary Fast Convergence (OSPFv2, IPv4 only) Fast Convergence allows you to define the speeds at which LSAs are originated and accepted, and reduce OSPFv2 end-to-end convergence time. FTOS enables you to accept and originate LSAa as soon as they are available to speed up route information propagation. Note that the faster the convergence, the more frequent the route calculations and updates. This will impact CPU utilization and may impact adjacency stability in larger topologies. Multi-Process OSPF (OSPFv2, IPv4 only) c e s z Multi-Process OSPF is supported on platforms and later, and is supported on OSPFv2 with IPv4 only. with FTOS version 7.8.1.0 Multi-Process OSPF allows multiple OSPFv2 processes on a single router. Multiple OSPFv2 processes allow for isolating routing domains, supporting multiple route policies and priorities in different domains, and creating smaller domains for easier management. Open Shortest Path First (OSPFv2 and OSPFv3) | 629