01-30-2008 07:11 AM - edited 03-05-2019 08:49 PM
Hi,
I have a 802.1q trunk and an ISL trunk conigured between two switches.
When I 'sh int trunk' the output shows the native vlan as 1 for both 802.1q AND ISL ?
Does 'native vlan' have any meaning within ISL ? I don't think it does but just need to confirm.
I think I have verified this in the following way:
I changed the native vlan on one end of each trunk (the 802.1q and ISL) respectfully and CDP only complains about NATIVE_VLAN_MISMATCH for the 802.1q trunk.
Regards,
Phil.
Solved! Go to Solution.
01-30-2008 07:18 AM
Hi Phil
Yes you are correct. ISL tags all frames and does not have a concept of a native vlan as such where the native vlan sends packets that do not have a vlan tag.
The native vlan in 802.1q was designed to allow compatability with older switches that did not support tagged frames.
HTH
Jon
01-30-2008 07:18 AM
Hi Phil
Yes you are correct. ISL tags all frames and does not have a concept of a native vlan as such where the native vlan sends packets that do not have a vlan tag.
The native vlan in 802.1q was designed to allow compatability with older switches that did not support tagged frames.
HTH
Jon
01-30-2008 07:19 AM
minor correction...ISL doesn't tag, it encapsulates. dot1q tags.
01-30-2008 07:21 AM
thanks :)
01-30-2008 07:23 AM
that was mainly for the benefit of the OP..
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide