How to see Spanning Tree traffic...Port #?
Posted on 2006-04-13
I have someone on my network that has hooked up a switch that is sending out VTP stuff that is messing with my cisco switch, and has apparently hooked up into another ISP service causing Spanning Tree to shut off the main Wan port on our Cisco switch periodically for about 1 minute at a time every 20 minutes or so. I'm trying to figure out who it is, so I set up a span port on my switch and am sniffing all the traffic but I'm not sure what I'm looking for exactly.
What port does spanning tree run on? UDP or TCP? Will I even be able to see it with a packet sniffer?