Tagging native VLAN both sides

[alistair777]

Hello,

I have been unable to find a succinct answer to this question so I thought I would ask on the official Cisco support forums.

If two switches are trunked together with 802.1Q and the native VLAN is tagged on one side with "(config)#vlan dot1q tag native" but the other side is not (untagged native VLAN) - provided that both the native VLANs match will this cause an issue?

Many thanks.

[Shaunak]

Hi Alistair777,

In my experience it doesn't work, if the native VLAN is used to transport data then the tagging of the native VLAN should be consistent on both the switches.

You may also test this in the lab as well, although I have seen it not to work.

Hope this helps.

Thanks,

Shaunak

[devils_advocate]

I found this article:

http://www.cisco.com/web/techdoc/dc/reference/cli/nxos/commands/l2/vlan_dot1Q_tag_native.html

It suggests that the side which is set to tag the native vlan will drop any non control frames it receives which do not have a vlan tag. 

Its not a normal configuration so you should expect odd results when using it.