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graceful-restart grace-period
Enable OSPFv3 graceful restart globally by setting the grace period (in seconds) that an OSPFv3 router’s neighbors continues
to advertise the router as adjacent during a graceful restart.
Syntax
graceful-restart grace-period seconds
To disable OSPFv3 graceful restart, enter no graceful-restart grace-period.
Parameters
seconds Time duration, in seconds, that specifies the duration of the restart process before
OSPFv3 terminates the process. The range is from 40 to 1800 seconds.
Defaults OSPFv3 graceful restart is disabled and functions in a helper-only role.
Command Modes ROUTER OSPFv3
Supported Modes Full—Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.2(0.0) Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
By default, OSPFv3 graceful restart is disabled and functions only in a helper role to help restarting
neighbor routers in their graceful restarts when it receives a Grace LSA.
To enable OSPFv3 graceful restart, enter the ipv6 router ospf command to enter OSPFv3 configuration
mode and then configure a grace period using the graceful-restart grace-period command. The grace
period is the length of time that OSPFv3 neighbors continue to advertise the restarting router as though
it is fully adjacent. When graceful restart is enabled (restarting role), an OSPFv3 restarting expects its
OSPFv3 neighbors to help when it restarts by not advertising the broken link.
When you enable the helper-reject role on an interface with the ipv6 ospf graceful-restart helper-
reject command, you reconfigure OSPFv3 graceful restart to function in a “restarting-only” role. In a
“restarting-only” role, OSPFv3 does not participate in the graceful restart of a neighbor.
graceful-restart mode
Specify the type of events that trigger an OSPFv3 graceful restart.
Syntax
graceful-restart mode {planned-only | unplanned-only}
To disable graceful restart mode, enter no graceful-restart mode.
Parameters
planned-only (OPTIONAL) Enter the keywords planned-only to indicate graceful restart is
supported in a planned restart condition only.
unplanned-only (OPTIONAL) Enter the keywords unplanned-only to indicate graceful restart is
supported in an unplanned restart condition only.
Defaults OSPFv3 graceful restart supports both planned and unplanned failures.
Command Modes ROUTER OSPFv3
Supported Modes Full—Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.2(0.0) Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
OSPFv3 graceful restart supports planned-only and/or unplanned-only restarts. The default is support for
both planned and unplanned restarts.
868 Open Shortest Path First (OSPFv2 and OSPFv3)