3500XL VTP issue?

[John Blakley]

All,

I've got a 3548-XL switch that I'm trying to configure for VTP. I know this switch is really old, so bear with me. I've got the latest and LAST IOS that Cisco came out with.

Configuring vtp on this switch is different first of all. I have to be in vlan database mode before I can configure it. That being said, I have a VTP server already on the network on a 2950 switch. This works good with my other 2950 switch, but the 3500xl won't work, but there's more to it than that.

I configure the following:

vlan database

vtp client

vtp domain CISCO

exit

When I get to the enable prompt, I do a show vtp status and my changes are shown. I don't receive vlans from my vtp server. Also, when I reboot (after writing changes) everything goes back to default on this switch for vtp only. (vtp mode is server, null domain, etc.)

Was this a known issue with the 3500s?

Thanks,

John

[Jon Marshall · Accepted solution]

John

I think what is happening is that if the switch cannot find a VTP server then it will not allow itself to be configured as a client.

When you configure it as a client -

1) can you check the trunk status to the VTP server

2) can you check the configuration revision number is less on the 3500XL.

3) Can you check that you aren't using a password

Also when you have the new switch connected just update the vlan database on the VTP server and see if the changes then propogate to the 3500.

Jon

[John Blakley]

Jon,

That was it :) I forgot to trunk my port.

Thanks,

John

[MUHAMMAD SHAHEEN]

Hi John,

I ran into similar problem a while back. Just 1 more things to add into what you already have listed.

The Switchport Interface on C3548 connecting to VTP server (Trunk port) will need follwing configurations applied

Switchport trunk encapsulation dot1q

switchport mode trunk

and 2950's Trunk port may need switchport mode trunk, in case it does not have up-to-date IOS.

this is due to the fact that C2950's only support dot1q trunking and C3500's switches support dot1q and ISL, but fails to auto-negotiate trunk protocols.

that should work well

Hope This Helps....

Shaheen