I have a 3750 with a port configured as an access port in vlan 109. Connected to this port is 3550 switch - all ports is vlan one.
On the 3750 I get messages to the effect that a Native VLAN mismatch is detected between the 2 switches. It seems to be cosmetic, as there are no apparent problems. Should the switch report this error even though the port is not a trunk?
We had the same problem between a 3400me and a 3550. Turned out certain IOS had a cdp bug which would cause these error messages. An IOS upgrade on our switches fixed the messsage. But like you already stated this is mostly cosmetic and others have mentioned just disabling cdp on the ports as access ports do not pass vlan info anyways and the switches won't care. Probably the easiest thing to do since it does not require an IOS upgrade.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...