vragotha Wed, 09/29/2010 - 23:57
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1. Delete the vlan.dat file in the flash and reload the switch


2. Change the mode to VTP transparent so it wont participate in VTP in the network

Mel Popple Thu, 09/30/2010 - 00:03
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You don't mention what VTP mode you are running in. Once a switch has a VTP domain name the only way to get it back to Null is via a reload.

If you are in either server or client VTP mode and the domain name has not ben configured the switch takes it's VTP domain name from the first VTP packets it sees from other switches - so it will always change its domain name unless you set it yourself to something different.

If you put it in transparent mode it won't do this. If operationally possible change the switch to transparent mode,you will then need to delete the vlan.dat and reload, if that doesn't clear the name you may have to TFTP the startup-config off the switch, delete the VTP domain name in the file and then tftp it back on the switch, then reload.


Mahesh Gohil Thu, 09/30/2010 - 00:16
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Hi siva ,

If you want to see nothing infront of vtp domain in output of sh vtp please run below command

#vlan database

#vtp domain ""

#sh vtp status
VTP Version                     : 2
Configuration Revision          : 0
Maximum VLANs supported locally : 254
Number of existing VLANs        : 13
VTP Operating Mode              : Server
VTP Domain Name                 :
VTP Pruning Mode                : Disabled



Peter Paluch Thu, 09/30/2010 - 00:34
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I am afraid the domain name cannot be removed without deleting the file flash:vlan.dat and reloading the switch. So far, I have not seen any way to do it otherwise. Removing the vlan.dat file will also delete your entire VLAN database configuration so if you are using the VTP Transparent mode, you can lose precious data. If you are running in a VTP domain then the VLAN database should be downloaded back after your switch reloads.

In any case, removing the VTP name and resetting it to the null value will cause some downtime.

Please note that if you are in VTP Transparent mode, then the VTP domain is mostly a cosmetic setting. Only the DTP uses the VTP domain name, and if you do not use the DTP then the VTP domain name is totally irrelevant.

Best regards,


EDIT: Sorry, I've had the answer incomplete for quite a long time and in the meantime, other friends here responded.


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