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cluster query

I have got a query regarding adding an additional L2 switch to a network.

I look after a manufacturing site which has 1 main comms room and 5 subcomms.

A total of 25 L2 switches and 2 L3 switches with redundant ISDN

I needed to had an additional L2 switch to an exiting cluster, in one of the sub comms. which I have dome before.

I preconfigured this new switch before hand, but left the vlan config out.

The one thing I forgot to do was change the vtp mode, which was set to client. I was intending to change it to a transparent status before i introduced it to the live network.

Anyway I added the switch to the existing stack and had problems adding it as a cluster member.

Looking at the current cluster config, I noticed that the cluster was configured incorrectly regarding a non exit cluster commander mac address. I presume this was down to this stack, being first preconfigured in a lab and then put in to a live environment.

Anyway I decide to go a head and remove the exiting cluster and create a new one.

One of the existing life stack switches was a vtp server, but for some reason (which I hope you people will enlighten me on this)

As soon as I removed this cluster config all the switches inherited the new switch vlan’s config, which in turn brought the network to a stand still.

Why would a vtp client overwrite a vtp server config when the cluster for that stack is removed?

I have since recreated this problem in a lab environment with the new switch in a vtp transparent status from the start and then change it to a client status to inherit the life vlan config and it all work correctly.

can some one enlighten me VTP once again.


Re: cluster query

Unfortunately, a VTP client can update a VTP server if it has a higher revision level when you attach it to the network. In fact, both client and server anounce their configurations, and there is nothing in the protocol format that tells you whether it is a client or a server talking. In fact, the only difference between client and server is whether the CLI will allow you to manipulate the database.

Here is a document with a really neat flash animation that tells you about it:

Kevin Dorrell


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