Re: Confusion on VTP pruning. posted 11/10/2008
Yes - it sounds like you understand this concept pretty well. If SW1
is the server and SW2 and SW3 are the clients, you enable VTP Pruning
on the server device - SW1. Now, if you have VLAN 20 client off of SW1
only, then VLAN 20 traffic will be dynamically "pruned" off of the
trunk links that lead to SW2 and SW3.
Pruning is dynamic, so if at any point you add clients to SW2 or SW3
for VLAN 20, pruning will adjust and send traffic to those switches
via the trunk links.
If you were to make VLAN 20 prune ineligible, then you could force
this VLAN traffic over links where it would have been pruned under the
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On Nov 10, 2008, at 4:09 AM, Shahnawaz Khot wrote:
I have confusion on pruning. Please help with your expert suggestions.
Let's suppose for following topology.
All three switches are interconnected by trunk links.
If SW1 is VTP server and I am enabling a pruning on server, it does
will enable in the entire VTP domain. SW2 and SW3 are clients in
Suppose SW1 has vlan 20 and I want to prune that vlan traffic to its
clients. Clients don't have any ports assigned to vlan 20.
I think the topology is pretty clear now.
So as the link is trunk carries all vlan traffic between SW2 and
VTP pruning will change anything by enabling on server (SW1)?
I think, it won't affect anything because both VTP clients have
In such lab scenarios, configuring VTP pruning eligibility list on
trunks connected to other clients will be an idea to resolve this?
I am talking about *switchport trunk pruning vlan* command on SW1
links to SW2 and SW3.
I have no idea how can we enable pruning with such topology Please
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