Given Distributed Switching is a paid-for
licenced service that hasn't been out for 12 months you inherently MUST
have a valid support contract with VMWare for this lot and as N1000
setup/config is a far from common or simple job I would strongly advise
you log this problem with VMWare support.
Please don't think I'm being unhelpful, I'm clearly more than happy
to help out in just about every way I can with SF questions but when
there are vendor experts that you've paid to answer this kind of
problem I would always suggest you go there first. Hope you understand.
http://serverfault.com/questions/104722/nexus-1000v-vem-fails-on-2-out-of-8-hosts