Redundant VTP servers in a single VTP domain for fail-over

jjgriffi · ‎03-12-2003

I am creating a redundant network (sort of...) where I have 2 Catalyst 6509's, each with a SUP2/MSFC2, connected with a 8Gbps EtherChannel trunk. The first 6509 (A) is the root bridge and the main vtp server for the resident vtp domain. The second 6509 (B) is the secondary root bridge. A and B are running HSRP between the MSFC's. Servers and access layer switches have 2 connections each, one to A and 1 to B. The access layer switches are all vtp clients.

I want to make B a "secondary vtp server", so that in the event that A fails, B can automatically assume the function of the vtp server to preserve the vlan database. Is it possible to do this? If so how? As there is the command "set spantree root secondary" to designate a secondary root bridge, why is there not a similar command like "set vtp mode server secondary"?

Prashanth Krishnappa · ‎03-12-2003

There is no concept of secondary VTP server switch. However, you can have multiple VTP servers in the network for VTP server redundancy. Go ahead and set the VTP mode to server on the 6509-B and you should be set

jjgriffi · ‎03-13-2003

Will the 2 vtp servers "fight" each other or conflict with each other for vlan database updates? Can both vtp servers have the same vtp domain name?

rtr · ‎03-13-2003

Dear jjgriffi,

Two vtp servers within the same domain name is ok. The 2 will act together in your network. If you make a change on one, the second one will learn it and vice and versa. So no pb to declare the second 6509 as vtp server. There is no primary/secondary stuff in that case. Just vtp mode server on the two and the same vtp domain name.

I hope this answer your question.

Regards,

./RTR

jjgriffi · ‎03-13-2003

when I make the second 6509 a vtp server, will it erase any vlan database info learned as a vtp client? Should I paste in the vlan database config after making it a server, or will it learn from the first active vtp server?

Stephen Pearce · ‎03-13-2003

It will overwrite whatever is there but this box will still be in the same VTP domain so no difference. The one thing to check normally is that the version ID is lower on the new VTP server so as not to overwrite the existing server but again in your scenario it will be the same the the existing VTP server.