How to resolve Native Vlan Mismatch on two switch?

[Elrick Landon]

Hi to all

I have two switch, switch A (C9300) and switch B (C3850).

Switch A has three vlan: vlan 2000, 3000 and 4000.

Switch B has one vlan: vlan 1 (default)

Switch A is displaying log with:

CDP-4-NATIVE_VLAN_MISMATCH : Native VLAN mismatch discovered on GigabitEthernetX/X/X, with C3850#1 GigabitEthernetX/X/X

I precise that i use port-Based VLAN with no trunk (trunk is not usefull for my meaning).

All is working fine expect this message

Does this message is important ? How can i fix it?

Does it is better to define VLAN1 as VLAN2000 on Switch B?

Many thanks for your help.

[spunner]

Thanks for the reply.  They are plugged into a FPR1010 all are switchports on the firepower as well.  The firepower doesn't designate it's ports with three characters "1/0/2", just 2 characters "1/2" so it isn't complaining about that, it has to be the switch itself.  

[spunner]

I just enabled "protected port" we'll see if that does anything...besides break my network

[spunner]

That seemed to do the trick!  Not sure how you do that in CLI, but it fixed the errors and didn't break my network.

[Richard Burts]

Thanks for the update. Glad it seems to be working.