[c-nsp] VSS to vPC - vPC to Etherchannel

[Joseph Hardeman]

Hi Everyone,

I saw a very strange thing tonight while putting some vPC ports to a some
access switches.  So my Topology is a VSS stack to a pair of 5010 over vPC.
 I then have an active vPC from the 5010's to one 2960G port-channel.  I
now have this connected to several other 2960G's that are connected over
port-channels and I was wanting to connect those 2960's directly to the
5010 over vPC,  Just like the first one is, for failover and redundancy.
 Now with the ports on the 5010 in shutdown and the port channel in
shutdown, as soon as I apply the config on the port connected to a 2960,
the ports on the 2960 go from down/down to up/up even though the 5010 ports
are shutdown.

So several questions, why would the ports on the 2960's come up and what
can I check to see if something else is happening.  Second, is this path a
support configuration?  I mean, I have been told that its not "Supported By
Cisco" so that is their way of saying "weird stuff will happen".

If I can't have vPC going to my VSS engines and then on the other side have
vPC going to another switch, then there goes the benefit of using VSS or
vPC and I might as well have just put everything down single links and not
even worried about providing instant failover on the chance I loose one of
the VSS Engines or a vPC switch.

Any thoughts on what I am seeing?  I haven't seen anything like it before.

Thanks

Joe