VTP Client With Higher Revision Number (VTP Server Domain " ")

[Piwo]

Let s supose the scenario

VTP Server (Domain "  ", Revision Number 1) - VTP Transparent (Domain "  ", Revision Number 0) - VTP Client (Domain "cisco", Revision Number 3)

Will the  VTP client switch update the name of VTP Server switch to "cisco" and syn the rev number to 3?

I have just have doubts about the domain once the VTP Server is "  ".

I think the answer is yes, but I can t confirm with real equipment at the moment and in packet tracer it didn t work.

Thank you for your support

[Francesco Molino]

Hi

A vtp server is also vtp client. This means that any vtp client with higher revision can overwrite a vtp server within the same domain.

The answer to your question would be yes if the domain was the same. But in your case domain names are different and this means other switches will ignore the vtp advertisement.

Hope that helps.

[Piwo]

Hi Francesco,

Thank you for your quick answer.

I completly agree with your statement but this is a special scenario :

The domain is still empty, there is no domain for server and for transparent.

For example when :

VTP Server (Domain "cisco", Revision Number 3) - VTP Transparent (Domain "  ", Revision Number 0) - VTP Client (Domain " ", Revision Number 1)

Switch VTP Client gets the "cisco" Domain name through the Server.

In the following scenario I am not sure if VTP Server gets the Domain name as the VTP Client as a higher revision number  :

VTP Server (Domain " ", Revision Number 0) - VTP Transparent (Domain "  ", Revision Number 0) - VTP Client (Domain "cisco ", Revision Number 3)

Note : If there are diferent domains I am aware it will not work. But this is a special scenario with an empty domain.

Thank you

Regards

VTP

[Francesco Molino]

Hi

an empty value is still a value and it should work as expected meaning it shouldn't overwrite the existing vtp server.
Because when the server will receive the advertisement of vtp domain "cisco", it has to simply drop it.

[Julio E. Moisa]

Hi

As Francesco mentioned, it should not overwrite the vlan database, a good practice is set up a new switch with transparent mode before to be install it into the infrastructure. 

[Piwo]

Hi Francesco and Julio,

Thank you for your feedback and explanation !

I have just got confused because when we have the following scenariowith a empty domain the server updates the client with his vtp domain, in this case "cisco". In the below example VTP client gets the name "cisco" even being in a diferent domain..." " initial domain. This I have tested and it works like this :

VTP Server (Domain "cisco", Revision Number 3) - VTP Transparent (Domain "  ", Revision Number 0) - VTP Client (Domain " ", Revision Number 1)

But according your reply, even if the VTP Client when has a higher revision number in the following scneario is not accepted his VTP domain is not accepted. I wrongly thought that the client would act as a "server" has a higher revision number...

VTP Client (Domain "cisco", Revision Number 3) - VTP Transparent (Domain "  ", Revision Number 0) - VTP Server (Domain " ", Revision Number 1)

[Francesco Molino · Accepted solution]

Hi

Again, when the client will send advertisement, its domain will be cisco and on the other end the domain isn't cisco then the advertisement is dropped.

You can validate that by doing a wireshark while connecting it.

But you should prepare/review the vtp of any switches before connecting it to the network. Do a vtp transparent and then vtp client with all information to be sure its revision will be 0.