[c-nsp] Cisco 7600 and 'show mfib' commands

[John Neiberger]

I'm at a new job and was looking at a few recent trouble tickets. I see
that TAC had them use variations of the 'show mfib' commands, like 'show
mfib linecard summary'. At my previous job, we had a few hundred 7600s but
I don't recall TAC ever directing us to use those commands. I took a peek
at them and it's not clear what I'm looking at.

When I see mfib, I assume multicast FIB. I can't really tell if that's what
I'm looking at or not, or the significance of the commands.

I wasn't able to find much good info about these commands on CCO. Do any of
you have any idea what these are really looking at? It seems that they
might be useful for troubleshooting linecard issues but I'm entirely
unfamiliar with them.