A network engineer must enable the helper router to terminate the OSPF graceful restart process if it detects any changes in the LSA.
Which command enables this feature?
A. nsf ietf helper disable
B. nsf cisco helper disable
C. nsf ietf helper strict-lsa-checking
D. nsf cisco enforce global
This is wrong I think… Directly from the documentation:
Disabling Graceful Restart Helper Mode and Configuring Strict LSA Checking on the Helper Router
The graceful restart helper mode feature is enabled by default. It is not recommended to disable helper mode because the disabled neighbor will detect the lost adjacency and the graceful restart process will be terminated on the restarting neighbor router.
The strict LSA checking feature allows a helper router to terminate the graceful restart process if it detects a changed LSA that would cause flooding during the graceful restart process. Strict LSA checking is disabled by default. You can enable strict LSA checking on an OSPF helper to have the router terminate graceful restart when there is a change to an LSA that would be flooded to the restarting router. You can configure strict LSA checking on both NSF-aware and NSF-capable routers; however, this feature will become effective only when the router is in helper mode.
I believe based on the documentation the correct answer is C.