Cisco NSR use cases

[nwekechampion]

Hi guys,

Was just looking to see if anyone can explain why and how NSR happens in a dual RP system.

For example between a PE-CE (EBGP)

and when running with OSPF and ISIS?

[MHM Cisco World]

NSR happened between RP in same device or device that run vss or stackwise virtual 

It not happend between two different standalone devices.

[M02@rt37 · Accepted solution]

Hello @nwekechampion,

In the context of VSS or StackWise Virtual, NSR ensures that routing and forwarding are maintained even if one RP in the same device fails.

With PE-CE connections using BGP, OSPF, or ISIS, NSR ensures that BGP sessions are maintained, and BGP

adjacencies

are quickly re-established on the standby RP in case of an RP failure. Also, NSR ensures that OSPF/ISIS

adjacencies

and link state databases are synchronized, allowing for a smooth transition of control plane operations to the standby RP in the event of a failure.

[nwekechampion]

Thanks M02@rt37