OSPFv3 Commands 957
Default Configuration
OSPF may act as a helpful neighbor for both planned and unplanned restarts
Command Mode
Router OSPFv3 Configuration mode
User Guidelines
The grace LSA announcing the graceful restart includes a restart reason.
Reasons 1 (software restart) and 2 (software reload/upgrade) are considered
planned restarts. Reasons 0 (unknown) and 3 (switch to redundant control
processor) are considered unplanned restarts.
nsf ietf helper disable is functionally equivalent to no nsf helper and is
supported solely for IS CLI compatibility.
Example
–
nsf helper strict-lsa-checking
Use the nsf-helper strict-lsa-checking command to require that an OSPF
helpful neighbor exit helper mode whenever a topology change occurs. Use
the “no” form of this command to allow OSPF to continue as a helpful
neighbor in spite of topology changes.
Syntax
nsf [ietf ] helper strict-lsa-checking
no nsf [ietf ] helper strict-lsa-checking
•
ietf
—This keyword is used to distinguish the IETF standard
implementation of graceful restart from other implementations. Since the
IETF implementation is the only one supported, this keyword is optional.
Default Configuration
A helpful neighbor exits helper mode when a topology change occurs.