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Need help with %SPANTREE-5-TOPOTRAP and managment vlan change!



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 portfast
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.

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 - Do not use these commands on (up) link ports : 
         spanning-tree portfast
         spanning-tree bpdufilter enable


-- ' A nun once asked a penguin ' do you think the earth is flat ? ; the penguin replied :
Madam, it all depends , in Riemann geometries the earth can be perfectly flat! The nun thanked him , he tripped and fell forward : the poor animal had forgotten that he might be living in a Riemann geometry too!


I do not believe that message should cause concern.  That message just appears as there was a topology change when you made the changes.  

If there is a timestamp on that message, you may be able to back track exactly what you were doing when that message appeared.

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