[c-nsp] VSS - Horror stories, show-stoppers, other personal experience?

[Jason Gurtz]

> Has anyone had personal experience with a VSS deployment?  If so, do you
> have any horror stories, caveats, and/or recommendations?  I'm also
> interested in people's experience with IPv6 implementation in a VSS
> environment.

Another BU runs a pair of VSS systems here as cores for a MAN network.
They primarily do Q-in-Q tunneling to extend the reach of L2 networks. It
is a hybrid approach and they have some VLANs in a star topology using
port aggs and also bridged to some attached L2 rings. Lotta L2 going on...

This network was initially not VSS and they decided to add it for
redundancy. We had one crash/reboot recently but did not open a TAC case.
The last thing in the log was a "VSL Down" type error. The VSL is a single
10G link sup to sup. Maybe someone bumped the connector? Interesting that
it would cause an attempted failover and reboot of active sup.

SXH train is running, so a move to SXI would probably be a good idea as
well as configuring additional VSLs on the line cards. The spanning tree
took about 5 min to settle out which is how we discovered the issue. Can't
wait to retire our old 3Com based L2 network trunked to this thing!

The only other weird thing I can think of is their sales rep screwed the
pooch; the initial chassis is a 6509-V-E and the 2nd chassis in 6509-E
(cards horz.) Fugly, but it works and they don't care :)

~JasonG