VTP not working with switch not directly connected

[Sean McQuade]

Hi guys,

We have a 3750X VTP Server and the rest of the switches are clients.

Due to cabling issues, we have a switch (Switch F) that we can't connect directly to the 3750X so we have it connected through another switch. Everything is set to VTP client with the correct domain and password but this not-directly-connected switch isn't receiving any VTP VLANs.

Anything I need to do on Switch D so that Switch F can receive the VTP updates?

Thanks

Sean

[Giuseppe Larosa]

Hello Sean,

VTP messages travel on trunk links so you should verify if the link between Switch D and Switch F is a trunk or not.

You can use

show interface typex/y switchport

check for both administrative and operational status on both sides.

Besides this, you have also to check if the VTP domain name on switch F is the same as on the other switches.

You can use

show vtp status

for this.

If you are using MD5 authentication this is another possible source of mismatches,

the best you can do is to copy past the MD5 password from another switch instead of typing it.

Generally speaking your network scenario is supported there is no need of direct connection to the VTP server.

Hope to help

Giuseppe

[Alessio Andreoli · Accepted solution]

Hi Sean,

the first thing to do would be to force an updates to all the domain from the VTP Server. You could create for example, a vlan that does not exist and then removing it. This would force an update to the entire domain and should fixx your issue. If this does not work then you should re-check:

- show cdp neigh det ! On switch D

- show spanning-tree ! On switch D to check if that port is in blocking for any reason

- re-write the password authentication to make sure that no spaces have been included and checking the hash code

- to check the VTP version on switch F and D

Let me know

Alessio

[Sean McQuade]

Thanks guys, I forced the update on the server and this seemed to fix the issue. Thanks for your help.