While I was beginning on doing some work from the lab workbook, I loaded some pre-configured configurations that I saved so I would not have to go back and do all of the vlan creation, assignments and trunk ports. I loaded them and all was well. I verified my trunk links as well. I skipped the 802.1d section and went straight to MIST. I began my configuration and all went well. Convergence was ok as far as I could tell. I then moved to the next secion to assign loop guard and udld to all trunk ports. Well, as I was doing the configuration, most of my trunk ports started failing and complaing about UDLD detection and most of my trunk interfaces went into errdisable state except for one. I did a debug udld events and could see nothing out of the ordinary. I began to re-enable my trunk links and all went well and no more UDLD detections. Has anyone else experienced this with MST or any other type of STP?