VLAN int to be down when no physical interfaces are up

Unanswered Question
Mar 22nd, 2007

Very simple question:

I have a core switch. I want a specific VLAN IP interface to be declared as "down" when no physical interfaces using it are available (access ports or trunks).

I don't want this core switch to propagate a route to which is has no real connectivity.

So far, I can see that if the vlan exists in the vlan database, and an IP address was assigned, this is enough to make its line protocol be "up" (when executing "show int vlan x").

I want it to look like:

switch#sho int vlan X

VlanX is up, line protocol is down

Do you know if a vlan lan protocol state can be associated to a physical interface lan protocol state?

This may be related to shutting down the vlan internally in the switch. Don't know how to make this happen automatically.


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glen.grant Thu, 03/22/2007 - 16:19

It should not be up if the vlan is not being used as a access port or allowed across a trunk . I would take a closer look it is probably up somewhere or the vlan is allowed across a ctive trunk link .

ewaizel Thu, 03/22/2007 - 17:38

Thanks Glen

There is a trunk allowing this VLAN. Nevertheless, the trunk is down. The VLAN is still up. Strange, don't you think?

This is a 6509 running 12.2


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