vlan ports dissapered when delete

[Farrukh Husain Siddiqui]

Hi all,
I want to know why assigned ports getting inactive after deleting a vlan,why these ports are not automatically take membership of native or default vlans? Please tell technical reason.

Thank you.


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[chandra_rc16]

Hi Husain,

As of my experience with VLAN's, once you delete it, the ports in that VLAN will be redirected to the native vlan.

Regards,
Chandu

[Farrukh Husain Siddiqui]

Hello chandu,

I did the same on packet tracer with 3550 cisco switch, i also did on 3560 xl switch in my office, the results are same, ports inactive when we delete their associated vlan.
I want to know the reason.


Thank you

FH

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[Vlad Ovidiu Coras]

Right, once you remove the VLAN the port is inactive as it will stay in that VLAN and there is no spanning-tree instance for that VLAN. You will have to manually move the port to a different VLAN.

Why is it not automatically moved to a different VLAN? Not sure, but be carefull that Native VLAN only exists for trunk links. So then the question is to what VLAN should it be moved?

Best regards,

Vlad

[Kevin Dorrell]

I think it would be a security problem if the access port changed VLAN.  As it is, when you delete a VLAN, any access port on the VLAN is effectively disconnected.  If you have deleted its VLAN, you don't really want it to have any access until the host has been reconfigured.

If you have deleted a VLAN and forgotten you have some access ports on it, then you don't really want to give those ports access to who-knows-what VLAN.

Kevin Dorrell

Luxembourg