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New Member

Native Vlan Mismatch on Switch LD connected to

I am running 3 switches each with the same 3 vlans. I also have 2 local directors in failover mode. The primary has interfaces connected to switch one and the secondary has interfaces to switch two. Trunking is disabled on all device ports but enabled on a dedicated fiber connection between the 2 switches

The first vlan is vlan 1 for management

The second is vlan 2 for the gateway side of the local directors

The third is vlan 3 for the server side of the local directors

On the primary switch I am logging CDP messages telling me i have a native vlan mismatch on the 2 local director ports. The secondary switch I dont get these messages.

Any ideas what is going on here and why? Thanks, Art.

2 REPLIES
New Member

Re: Native Vlan Mismatch on Switch LD connected to

I get the same thign. I am guessing because the LD is stating that he us using vlan one, while you are using vlan 3 or 2. It is a CDP message only, not an actual error causing degradation, So I disabled CDP on that interface on the switch (As well you can disable it on the LD)

I think our failovers don't make the error, because they are not active.

New Member

Re: Native Vlan Mismatch on Switch LD connected to

You mention above " but trunking is enabled on a dedicated fiber connection between the two switches", therefore trunking is enabled.

Because trunked ports need to be assigned to the same native vlan, I would do a "show trunk" and verify that the port used for trunking on each switch, are assigned to the same native vlan, I've seen the mismatch if the are not. That command above is if your switch is using CatalystOS, otherwise, use this command for NativeOS - sh int fast 0/1 switchport and look for the "trunking native mode vlan" number. They must match on each side. To correct the problem, do set vlan 1 4/10 to assign port 4/10 to vlan 1 which, is your management vlan which I assume you've choosen to be your native vlan.

Hope this helps.

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