>> By the way, the first time this happened it wasn't following a >> reload or crash of the Cat6k. If I remember correctly, it coincided >> with someone connecting a Cisco 3020 blade switch, which we expected >> to be the cause. I think that incident led to us blocking >> 01000c-cccccd wherever we can. Still, I don't understand why it >> happens and how we can completely avoid it. > > We don't use MST, so take this with a pinch of salt... > > During my reading, I seem to recall that Cisco devices perform some > kind > of PVST->MST integration at ports at the "edge" of an MST cloud: > > http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.2SX/con figuration/guide/spantree.html#wp1098679
Since all our HP's connected to the Cisco's are running RSTP (and the Cisco's MST), I guess each Cisco port leading to a HP switch is considered a boundary port. > Is this your issue? > > http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.2SX/con figuration/guide/stp_enha.html#wp1054786 Yes, that's what happens... so we could also enable PVST Simulation again, hoping that receiving a PVST+ BPDU doesn't result in a "peer inconsistent" state. But still, I'd prefer killing this protocol entirely. It's > The problem is that if you've got non-Cisco switches downstream which > are a) MST enabled but b) still pass PVST PDUs, then you're going to > see "PVST peer inconsistent" on the port on the Cisco, not at the > edge of the network. Right, that's what happens. And what I'm trying to achieve is that the Cisco Cat6k completely *ignores* these proprietary PVST+ frames... Maybe it's me, but I just don't understand why I can't just disable all PVST+ "features". Other proprietary protocols such as DTP can also be turned off (at least at port level), so why not PVST+? But let's not go on a complete rant here... perhaps enabling PVST Simulation again will prevent the Cisco ports to go blocking; I'll test that in a service window. Thanks again for your comments and insights. Regards, Jeroen van Ingen ICT Service Centre University of Twente, P.O.Box 217, 7500 AE Enschede, The Netherlands _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
