DTP syslog entry when moving a switch from vtp client to vtp transparent

Beat.Traber · ‎05-15-2008

I'm currently changing the vtp mode in all my access switches in my datacenter from CLIENT to TRANSPARENT. When doing this on a Catalyst WS-C2950G-24-EI I received a syslog message that said

"May 15 13:39:02.871: %DTP-5-DOMAINMISMATCH: Unable to perform trunk negotiation on port Gi0/2 because of VTP domain mismatch"

Behind Gi0/2 (a 802.1Q trunk) is a Catalyst 6509-E which is VTP SERVER.

Theory says I would have to add "switchport nonegotiate" on this trunk. Do I have to do this even if I subsequently change the Cat 6509-E into a VTP TRANSPARENT too?

In other words: does this domainmismatch-thing happen only if there is a vtp server and a vtp transparent on the same trunk? What happens, if both devices are vtp transparent?

Thanks for any suggestions.

Rajat Chauhan · ‎06-06-2008

Depends on vtp version. In v2, if domain name matches, vtp updates are passed through vtp transparent device, else we see this message and no updates are passed through. V1 doesnt looks after domain name at all and doesnt let updates got through itself.

HTH

Raj