I'm trying to understand "%SPANTREE-5-TOPOTRAP: Topology Change Trap for vlan X" log line. Could someone explain this to me, I'm a beginner in networking and switch configuration in general.
I'm suspecting this topology change notification be the alert why my whole network went down. I was changing the management vlan for all switches, the route I took was, firstly add the new vlan, give it ip address and mask to all the switches, then after that removed the old managment vlan ip address/mask olny from two switches and not from the core switch, but from a regular one in the building.
Before all that I trunked all link ports with the new vlan and double checked it.
Did I need to add these commands to the link ports? Could I accidentally made a loop in the network?
spanning-tree bpdufilter enable
Any advice would be welcome and thanks in advance.
In the network I have Cisco Catalyst C9200L and C9300-NM switches approx 13 switches, core switch Cisco Catalyst WS-C3650, and two old 10 port HP ProCurves Switches, witch are in the topology of the network at the ends.