VTP Domain Name and Transparent Mode

[rlmosko01]

Can two switches connect via a trunk, one as a server and one as transparent and be in two different VTP domains respectively?

[mahmoodmkl]

HI

U want just physical connection or u want the vlan info to sync with the other switch.

First if a switch is in VTP transparent mode it doesnt sync with vtp messages but it can forward u r vtp messages to other switches if u r using vtp version 2.

And if they are in two diff vtp domains they cannot exchange any vlan info.

Thanks

Mahmood

[rlmosko01]

Unfortunatly I need them to pass vlan information. I just have to give up and accept this implementation isn't going to work. I'll have to eliminate the two transparent switches. Thanks.

[lburleso]

Another suggestion... not sure what the overall goal is, but I think 802.1Q/Layer 2 protocol tunneling would work in this case:

Configuring 802.1Q and Layer 2 Protocol Tunneling

http://www.cisco.com/en/US/products/hw/switches/ps4324/products_configuration_guide_chapter09186a008062cf6c.html

[devang_etcom]

hi,,,

ya two switches can connect using trunk link...u can configure one switch as server and one as transparent but they must be in one vtp domain in order to make consistent switching network topology...

regards

Devang

[rlmosko01]

I figured that was the issue. I have 4 switches in all. 1) Server, 2) Transparent_1, 3)Transparent_2 and 4)Client. I need the Server(1) to communicate with the Client(4) through the two transparent switches(2&3). The two transparent switches are in a different VTP Domain than the Server and Client switch. According to your answer, this will not work unless all switches are in the same VTP Domain?

[ankurbhasin]

Hi Friend,

AFAIK in VTP version 1, a VTP transparent switch inspects VTP messages for the domain name and version and forwards a message only if the version and domain name match. Because VTP version 2 supports only one domain, it forwards VTP messages in transparent mode without inspecting the version and domain name.

Can you confim if you are running vtp version 1 or version 2?

Regards,

Ankur

[rlmosko01]

The switches are all configured for Version 2. I'm thinking it may not inspect the vlan information but it does inspect the domain name????

[devang_etcom]

hi...

u mean to say your vtp mesg are not forwarded...right

r u sure all switches runing version 2

regards

Devang

[rlmosko01]

All switches are running version 2, however the switch that is furthest away(client) has not receive an update from the VTP Server because the transparent switches are not sending the vlan information or vtp updates.

[rlmosko01]

I found the following on Cisco web:

Error Message DTP-5-DOMAINMISMATCH: Unable to perform trunk negotiation on port

[chars] because of VTP domain mismatch.

Explanation This message means that the two ports involved in trunk negotiation belong to different VTP domains. Trunking is possible only when the ports involved belong to the same VTP domain. [chars] is the name of the interface.

[devang_etcom]

it means there is no trunk link formation between server and 1st transperent switch as well as there is no trunk between 2nd transperent switch and client switch...right due to domain miss match...

only trunk will form between two transperent switch...because of same domain ...right

regards

Devang

[lburleso]

Try the following suggestions:

1. As a best practice, use nonegotiate everywhere.

2. On the specific ports we are discussing in this thread, also try the following commands:

switchport mode trunk

switchport trunk allowed vlan ###

switchport trunk pruning vlan none

[devang_etcom]

can u send me the configuration of all switches...

regards

Devang

[rlmosko01]

You are correct. I've attached a word doc with all the information I have. Thanks for your help.