VTP (Pssword)

Hi All,

Been doing some labbing on VLANs and VTP and a bit puzzled.

I have Switch 1, a VTP server with a domain name set and a password set. I created a few test vlans.

I then take Switch 2 with no vlans expect the "out the box" defaults.
I had it in transparent mode first, then converted it to client mode. Now I understand it will pick up the server vtp domain name (if it already doesn't have one). However, because I didn't configure a password on the client switch I didn't expect it to learn all the vlans from the server, but it did.
What is this password for? I thought it was some sort of security feature so that all the switches in the domain had to use it before any vlan data could be passed successfully. In my lab this doesn't seem to be the case. I have it configured on my server, but not the client and still the client was passed all the vlan info.

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Comments

YFZblu

Hmmmm according to Cisco a switch will reject VTP updates if the domain requires a password and you haven't manually configured one yet. Have you blown out the configs and tried again?

control

Yeah, wiped the configs, including the vlan.dat file. Done it a few times just to make sure I wasn't going mad. Will test this all again tomorrow, a bit baffled at the moment.

fsanyee

VTP takes the domain name and the password too if it was blank.

control

fsanyee wrote: »

VTP takes the domain name and the password too if it was blank.

Just tested again as I thought I was going mad...same results. However when I go to my client switch and do a show vtp password. It says no password configured. So is it really taking the password?

On a side note...how do I remove the current VTP Domain name and set it to Null again?

Thanks

fsanyee

I dont think you can do that. You have to delete the vlan.dat file.