[c-nsp] Trunking Catalyst to HP Procurve...

[Jeff Kell]

Hopefully this will ring a bell with someone that has "been there done 
that" and can save me a road trip with a sniffer...

We recently added a few HP ProCurve switches (2810s) at the access layer 
using simple trunks back to our existing Ciscos (2950/2960/3550/3560s).

All is well with the exception that our network monitoring is turning up 
discards on the trunks (roughly every 10 seconds).

I've tried disabling all of the negotiations that I can think of, e.g.,:

> interface GigabitEthernet0/1
>  description FLT-Uplink-2
>  switchport mode trunk
>  switchport nonegotiate
>  no cdp enable
> end

but the discards continue.

Also getting a *lot* of noisy spanning tree traffic seen on the Cisco side:

>      Protocol       Path    Pkts In   Chars In   Pkts Out  Chars Out
>     
> Spanning Tree    Process   17447867 1099182989       3219     204892

Ciscos are trunning default PVST, HPs are doing whatever they do out of 
the box.  Not sure if this is an issue or just brain-dead old Catalyst 
"show int switching" counter bug :-)

Things seem to be working, but then there isn't much traffic in this 
building.  It just doesn't "look" right.

Any suggestions would be appreciated.  Thanks...

Jeff