My guess is that you don't have a root switch defined and the new switch became root
On Jun 4, 2013, at 7:41 PM, "Michael Sprouffske" <[email protected]> wrote: > This was most definitely a topology change. Happened when this outage > occured. > > > > > ________________________________ > From: Pete Templin <[email protected]> > To: Michael Sprouffske <[email protected]> > Cc: "[email protected]" <[email protected]> > Sent: Tuesday, June 4, 2013 4:24 PM > Subject: Re: [c-nsp] Possible spanning tree issue > > > On 6/4/13 3:56 PM, Michael Sprouffske wrote: >> I attached a new switch to the network and it took down our contact >> center that doesn't touch this switch nor does the phone system. Is >> this spanning tree doing this? I don't see anything in the logs that >> show a change in spanning tree. >> >> I also had an employee unplug a switch by accident and it took down >> our contact center. This switch is all by itself and does not >> directly touch the phone system nor is it in the path of the phone >> system. I feel like this shouldn't have happened. > > You won't see anything in the logs regarding STP changes unless you're > running a debug before/during/after and you are logging at the debug > level. Do "sh spann det | inc gy changes" on a switch and see if one or > more VLANs had a topology change about the time this event happened. If > it's more recent than that, the commands after the next paragraph may > become quite important. > > At this very moment, I would highly suggest that you stop whatever else > you're doing and embark on a priority-1 project to assess and define > your STP root placement. I suspect, reading between the lines of your > post, that you haven't done much to select where it is, and you're > experiencing a change in root placement. I'd strongly suggest assessing > whether any of the following make sense in your environment: > > Global: > spanning-tree vlan 1-4094 pri 8192 > spanning-tree portfast default > spanning-tree portfast bpdufilter default > > Interface: > no spanning-tree portfast > spanning-tree portfast trunk > spanning-tree bpduguard enable > spanning-tree guard root > > pt > _______________________________________________ > cisco-nsp mailing list [email protected] > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
