OcNOS-SP : Layer 3 Guide : Open Shortest Path First Command Reference : OSPFv3 Graceful Restart Commands
OSPFv3 Graceful Restart Commands
This chapter describes the OSPFv3 graceful restart commands.
capability restart
Use this command to enable OSPFv3 graceful restart capability. If a router is not restart-enabled, it cannot enter graceful restart mode and act as a helper.
Use the no parameter with this command to disable the feature.
Command Syntax
capability restart graceful
no capability restart
Parameter
None
Default
By default, capability restart graceful is enabled
Command Mode
Router mode
Applicability
This command was introduced before OcNOS version 1.3.
Examples
#configure terminal
(config)#router ipv6 ospf 100
(config-router)#capability restart graceful
 
(config)#router ipv6 ospf 100
(config-router)#no capability restart
ipv6 ospf restart grace-period
Use this command to enable the graceful restart feature and set the grace period for restarting the router.
If graceful restart is enabled, NSM is notified about the grace period. If the OSPF daemon unexpectedly shuts down, NSM sends this value to the OSPF daemon when it comes up again which uses this value to end the graceful state.
Use the no parameter with this command to revert to the default grace period.
Command Syntax
ipv6 ospf restart grace-period <2-1800>
no ipv6 ospf restart grace-period
Parameters
<2-1800>
Grace period in seconds.
Default
By default, grace period is 120 seconds
Command Mode
Configure mode
Applicability
This command was introduced before OcNOS version 1.3.
Examples
#configure terminal
(config)#ipv6 ospf restart grace-period 250
ipv6 ospf restart helper
Use this command to configure the helper behavior for graceful restart.
Use the no parameter with this command to revert to the default.
Command Syntax
ipv6 ospf restart helper {max-grace-period <2-1800>}
ipv6 ospf restart helper never (router-id A.B.C.D|)
no ipv6 ospf restart helper
no ipv6 ospf restart helper never
no ipv6 ospf restart helper {max-grace-period|never router-id (A.B.C.D|all)}
Parameters
<2-1800>
Help only if received grace-period is less than this value.
A.B.C.D
Router ID of neighbor to never to act as helper.
never
Prevent the neighbor from entering helper mode.
max-grace-period

Help only if received grace-period is less than this value.
router-id
Router of neighbor to never to act as helper.
Default
By default, router behave as helper. To disable it as helper, ospf restart helper never command should be configured. ospf restart helper max-grace-period – Max-grace-period to function as helper. If not configured, value will be the grace-period in restarting node.
Command Mode
Configure mode
Applicability
This command was introduced before OcNOS version 1.3.
Examples
#configure terminal
(config)#ipv6 ospf restart helper never router-id 1.1.1.1
 
#configure terminal
(config)#no ipv6 ospf restart helper never
ipv6 ospf restart planned-only
Use this command to configure the OSPFv3 GR support for only planned restart.
Use the no parameter with this command to revert to the default.
Note: OSPFv3 supports only planned restart. Hence this command configuration and un-configuration does not have any functionality impact
Command Syntax
ipv6 ospf restart planned-only
no ipv6 ospf restart planned-only
Parameters
None
Default
By default, OSPFv3 supports planned restart only.
Command Mode
Configure mode
Applicability
This command was introduced before OcNOS version 1.3.
Example
#configure terminal
(config)#ipv6 ospf restart planned-only
 
#configure terminal
(config)#no ipv6 ospf restart planned-only
 
restart ipv6 ospf graceful
Use this command to restart OSPFv3 gracefully.
After this command is executed, the router immediately shuts down. NSM is notified that OSPF has shut down gracefully. NSM preserves routes installed by OSPF until the grace period expires.
Command Syntax
restart ipv6 ospf graceful (grace-period <1-1800>|)
Parameters
<1-1800>
Grace period in seconds.
Default
By default, restart ipv6 ospf graceful is disabled. Default value of grace-period is 120 seconds.
Command Mode
Privileged Exec mode and Exec mode
Applicability
This command was introduced before OcNOS version 1.3.
Examples
#restart ipv6 ospf graceful grace-period 200
 
#restart ipv6 ospf graceful
% Warning : ipv6 OSPF process will stop and needs to restart manually,
You may loose ospf configuration, if not saved
Proceed for graceful restart? (y/n):y