VPC=S/MLT?

Wed Jan 18 17:57:05 UTC 2012

vpc has a long list of unclear and/or seemingly contradictory caveats
(spread across multiple cisco docs/webpages).  when it doesn't work
(as expected), it can be challenging to find someone with tac who can
actually tell you why (or how to fix it properly).  if your needs are
fairly basic, are all cisco, follow their dc3.0 verbatim, and don't
mind the lack of features on the nexus platform, then it isn't a bad
box (if rather expensive for the lack of features...like ipv6 for
is-is).  also, be prepared to keep spanning-tree around and keep
bugging your cisco se/am about trill support (as opposed to
fabricpath...see tdp vs ldp)

if you *might* want to involve the n7k in routing at all, then
http://bradhedlund.com/2010/12/16/routing-over-nexus-7000-vpc-peer-link-yes-and-no/
offers a much clearer explanation than cisco.com about what works and
what doesn't (and whether-or-not tac might try to help)

hth
/joshua