I've been researching using BFD (Bi-Directional Forwarding) instead of OSPF sub-second hello timers and I noticed there are some caveats in using NSF (Non-Stop Forwarding) and BFD together because apparently BFD can override the NSF process if it detects a link failure during SSO of RSPs.

See article here (still trying to find a date on the article to see how recent it is)

Are any of you guys using these two together on an SP Core?
Cisco was my first networking love, but my "other" router is a Mikrotik...


  • chrisonechrisone CISSP, CRTP, eCPPT, LFCS, CEH, Azure Fundamentals, Retired Cisco NPs Member Posts: 1,923 ■■■■■■■■□□
    ON my VSS pair, we use BFD for the VSL link. So if the VSL link breaks BFD can tell the chassis which one is the master and shut down the other chasses line cards, before a loop occurs with 2 master VSS chassis forming.

    We use NSF for our layer 3

    We use SSO between the Sups.
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