switch/Vlan

Hello everyone,

I have a question regarding vlans. this is the senario:

Suppose you have three switch interconnected each other and each one has several vlans connected to its ports. You are loged in one of the switches and would like to see which switch is providing vlan information to the switch that you are loged in.

I look forward an answer for this question and in advance I appreciate.

Enow

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Comments

yukky

Any switch with VTP Operating Mode: Server is setting VLAN information for other switches (not VTP Transparent).

I don't think there is a way to see which switches are setting to VTP Operating Mode: Server remotely.

show cdp entry, can show the VTP Management Domain and Native VLAN, however.

nice343

the only way switches can propagate vlan info is through VTP

to check vtp

use

show vtp status

Netstudent

nice343 wrote:
the only way switches can propagate vlan info is through VTP

to check vtp

use
show vtp status

right....At the bottom of the output you might see somehting like configuration last modified by x.x.x.x. That will be the management IP of your VTP server.

APA

Netstudent wrote:
nice343 wrote:
the only way switches can propagate vlan info is through VTP

to check vtp

use
show vtp status
right....At the bottom of the output you might see somehting like configuration last modified by x.x.x.x. That will be the management IP of your VTP server.

Spot on..... If VTP is setup and you have a server propagating vlan information to clients when you use 'show vtp status' on a client the output will show you the IP of the VTP server at the very bottom of the output.

If your on the server and you use 'show vtp status' you should realise before even hitting the bottom of the output that you are on the vtp server

yukky

Netstudent wrote:
nice343 wrote:
the only way switches can propagate vlan info is through VTP

to check vtp

use
show vtp status
right....At the bottom of the output you might see somehting like configuration last modified by x.x.x.x. That will be the management IP of your VTP server.

show vtp status won't always show you the whole picture, just the IP of the last VTP server to modify the VTP configuration. If you change the management IP of the switch afterwards, the other switches will still report that the old IP was the last one to update the VTP configuration. Also if you've got more than one switch set as a VTP server, you won't be able to see them all.