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New Member

effect on switchports of changing vtp domain

I have three switches in a single VTP domain (I actually have lots but 3 will be for this example) A and B are vtp servers C is a client.

I creat a VLAN100 on one switch A, this is propagated to the other switches. I set a port on C to be in VLAN100. I them put switch B and C in a new VTP domain and create VLAN100 in this domain.

Question - Does the switchport on switch C continue to operate on the new VLAN100 within the new VTP domain?


Re: effect on switchports of changing vtp domain

VTP advertise only over trunk link, so if you set a switchport to access, it will not advertsie VTP messages.

If you have VLAN 100 in the new VTP domain the port on C will work as before (tagging with VLAN 100 if not native vlan)



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Re: effect on switchports of changing vtp domain

New Member

Re: effect on switchports of changing vtp domain

Thanks for the post, I have looked at this and a number of other cases where people are trying to bring two VTP domains together. In these cases the VTP sync works. What I am trying to do is break a single vtp domain into several smaller ones with layer 3 links (rather than layer 2 trunks) between them. To keep my users downtime to a minimum I would like to preconfigure as much as possible, i.e. create the VLAN's and set the switchports, then change the VTP domain. Does a VLAN have a "magic number" which is specific to a VTP domain or will the VLAN port config work properly on the new domain.

It could be that I am being overly concerned here and that everything will "just work" but I have 600 users, data and voice, who will be down if it goes wrong!!