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Is there any option to trace vtp learning


Is there any option to trace through which switch port , switch has learned vlan database information?

Here we have two network segments. switch in one network segment overwritten the vlan database of all switches in other segment.




Re: Is there any option to trace vtp learning

The vlan database is a global database containing info on all vlans in the network. All devices in the vtp domain exchange vtp information regardless of their port-vlan assignments. Each device has a copy of the database in the vlan.dat file.

In your case, a (new) switch was installed in the network with a higher vtp configuration revision number. You should always make sure that the config-rev of a new device is lower than what is currently used on the network.

It is fairly simple to make a backup of the vlan config before you start and re-enter the database when this occurs.

Resetting the vtpo domain and reloading the device resets the revision number and avoids the problem.



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Re: Is there any option to trace vtp learning

on the switch command "show vtp status" you will get the following output

configuration last modified by --> will show you what switch has the highest revision number, also the vtp server switch

local updater ID --> Ip address of the switch where you run the command, it will also show you what interface is used to get/propagate the vtp info

B#show vtp status

VTP Version : 2

Configuration Revision : 44

Maximum VLANs supported locally : 1005

Number of existing VLANs : 30

VTP Operating Mode : Client

VTP Domain Name :

VTP Pruning Mode : Disabled

VTP V2 Mode : Disabled

VTP Traps Generation : Disabled

MD5 digest : 0xFB 0x8B 0xEF 0xAD 0x65 0xED 0x45 0x91

Configuration last modified by at 10-17-06 19:33:05

Local updater ID is on interface Vl1 (lowest numbered VLAN interface found)

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