Re: Native VLAN mismatch on Cisco 2950




Arthur Brain wrote:
bav...@xxxxxxxxx wrote:

2. I did some test and set all the ports in one of the 2950 to VLAN
10. Configure fa0/24 on the 2950 for trunking to Cisco 3750. Got
Native VLAN mismatch warning when issuing "show interface trunk" on
the 2950. Does this message indicates something is wrong or we can
have mismatch native vlan?

You can have it.

It just means that, on the trunk between them, your 3750 is treating
un-tagged frames as though they were VLAN 1, and your 2950 is treating
un-tagged frames as VLAN 10.

Basically a sign of poor design, but not *necessarily* of any problem.

Actually, I was just playing with an old 3548 switch, patched to a
trunk port on a 3750 and the 3548 was actually disabling ports where a
VLAN mismatch was detected.

.



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