VTP Client mode - does store vlan info in NVRAM ?

[edixon]

Hi All,

I know this topic has been covered earlier but nobody seems to of given a definitive answer.

Almost all of the documentation I can see says that a switch in VTP Client Mode does not store any vlan info into it's NVRAM.

My testing in the lab indicates this is not the case.

Scenario:

Configure switch X as the VTP server and switch Y as the VTP client in VTP domain TEST

Connect X -> Y via a trunk

Create VLAN 2 on switch X

VLAN 2 is then automatically created on switch Y

Disconnect the trunk link between X & Y

Power cycle switch Y

Isssue "Show VLAN" on switch Y and VLAN 2 is still present.

Whilst this is comforting behaviour for myself, I don't understand why this info conflicts with all the Cisco documentation. I am reading it incorrectly ?

Thanks,

Ellis Dixon

[ankurbhasin]

Hi Friend,

Can you confirm the procedure you are creating the vlan?

Regards

Ankur

[edixon]

Sure,

On switch "X" I enter configuration mode and type

"Vlan 99"

This creates me Vlan 99 on Switch X, moments later this Vlan appears on Switch Y.

Thanks,

Ellis

[ankurbhasin]

Hi Ellis,

Can you try something this way.

Instaed of creating vlan from global config mode go to vlan database mode from enable prompt and then create a vlan on your VTP server and let it be advertised to your vtp client switch and then remove the trunk connection and reload the vtp client switch and update if the vlan information is lost or not.

Regards,

Ankur

[edixon]

Hi Ankur,

I have just tested it from vlan database mode and I get the same result, the vlan remains on switch Y with no trunk connection after the power has been removed.

Thanks,

Ellis

[philth_123_2]

Ellis,

I have the same issue with my 3500 switches and agree with you. The vlan.dat file is maintained in NVRAM in Client mode. However, come the exam I may be tempted to answer that it doesn't as all the Cisco literature seems to indicate the opposite.

Regards,

Phil.