Native vlan mismatch

[cristian_neagu]

Hi guys,

I have a question.

I just enabled 2 vlans (30,40) in my network and I am getting some native vlan mismatch.

So my core switch is a Cisco 3750G PoE model and  6 switches are cisco 3500xl model. I have enabled vlans only on the core switch.

I will give you an example:

On port 12 of the core I have enabled Vlan 30 switch port mode access and is connecting to one 3500xl switch. There is no trunk between them. 

The thing is that on 4 switches I get native vlan mismatch but on 2 i do not.There is no trunk set up between them, I will probably do that in the nearest future. Just did a quick setup to separate the voice from the data.

I tried to setup in the core connection with one switch on the port where i get this error the native vlan 1. But i am still getting this error.

The curious case is why i am getting this only on 4 and not on all.

Any ideas? The only way to fix this is by enabling dot1q trunks between the switches and allowing the vlans?

Thanks,

[Horacio2021]

whenever you make   more vlans,you have to have the native vlan ,namely , the vlans in your switch 30,40,1 (native), for example

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3550/software/release/12-1_13_ea1/configuration/guide/3550scg/swvlan.html#wp1101186

[Mark Malone]

does each side switch to switch connection match as an access port , even if there not trunk you will still get a vlan mismatch even if its access vlan 10 on 1 side and access vlan 12 on the other as an example

[Joseph W. Doherty]

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Posting

I believe you can also "fix" by disabling CDP (on the port, if supported).

[rafaelti1]

Vlan 1 is native by default, if you specified a diff native vlan on one switch and did not set it on the other then you will have a native vlan mismatch. Can you post your configs so we can take a look?