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New Member

Mgmt Vlan connectivity issue following VTP problem

Hi all,

i had a vtp problem yesterday after an engineer connected a catalyst switch with higher revision number to my LAN; this caused an overwrite of the vlan info on the vtp server (6509); i recreated the vlan database on the server after disconnecting the rogue switch.

in my LAN, i have certain floors that have a 2950 and a 3550 in cascaded mode, the 3550s being connected to my core using G0/1 and to the 2950 using G0/2, with the mgmt vlan of all switches being 172.16.99.x.

Following this incident, my LMS server (.99.230) is able to reach only the 3550 switches, but not the 2950s. even from the 3550, i am unable to reach the directly connected 2950s, knowing that the trunk configs between the 2950s and 3550s are fine (has not been modified following incident).

any ideas please?



Re: Mgmt Vlan connectivity issue following VTP problem


How you configured the 2950 vtp mode, is it client/server. If the vtp mode is client then the vlans might have been removed from the 2950 switch after the incident.... In this case the trunk link will be up but there will be no traffic to the core as the vlans are not present.

Rate if this helps...



Re: Mgmt Vlan connectivity issue following VTP problem


Please check if the vlans you created are alive on the 2950s.

Also check the vlans carried by the trunks with the "show interface G0/x trunk" command.



New Member

Re: Mgmt Vlan connectivity issue following VTP problem

Hi again all,

as soon as i recreated the vlans on the vtp server, they got propagated again to the vtp clients. Note that end user connectivity is ok, the problem showing only on the 2950s' mgmt vlan.

what i did was to reload two switches showing this symptom, and it all went back to normal. my plan is to reload remaining units (5 of them)

any hints?