vlan mismatch on a non-trunk port?

[bwindle]

I have a 6500, running CatOS 7.6(2), directly connected to a 3500xl (running IOS 12.0(5)) with Cat5. I am *not* trunking between them. Each port is running under a different native VLANs, which I wouldn't think was an issue since they aren't trunking. The connection works fine, and packets flow between them as expected, but my 6500 complains about a native VLAN mismatch on that port. Is this a bug on the CatOS side? The 3500xl doesn't seem to complain about the native vlans being different.

[glen.grant]

This is a normal message and doesn't hurt anything , to get rid of it as you said put them both in the same native vlan or you can turn down the logging for cdp so that it doesn't report it , think these were cdp messages , just going off the top of my head.

[ankurbhasin]

Hi Bwindle,

There are CDP messages to confirm? Also if you are sure there is no trunk config then I am sure you have a vlan mismatch by which I mean the port which you have used to connect 2 switches are in different access vlan? Am I correct?

If yes there will be a data transfer but you will get this meesage and as GLEN suggested to make the vlan information same on both the sides or reduce the logging level for CDP or just disable CDp is possible.

HTH

Ankur

[bwindle]

Yes, these are CDP messages:

%CDP-4-NVLANMISMATCH:Native vlan mismatch detected on port 4/39

I am sure the port is not trunking:

Commons_6506_1> show trunk 4/39

Port Mode Encapsulation Status Native vlan

-------- ----------- ------------- ------------ -----------

4/39 off dot1q not-trunking 54

Each port is in a different access VLAN. I just thought it odd that the 6500 cared about the native vlans since there was no trunking, and thus, no native vlan (just the active vlan).

[ankurbhasin]

Hi Bwindle,

Yiu will get the same message if there is a vlan mismatch also. Cisco had develpoed a same error message for vlan mismatch as well as native vlan mismatch.

Also if you check sh cdp nei....you will see a "*" in front of this entry which indicate vlan mismatch.

It will work fine and you can ignore the erorr message but of you want to get rid of the same just make the vlan infirmation same on both the sides.

HTH

Ankur