Best way to configure native vlan + another vlans in interface

irenelobos · ‎03-05-2014

I have to 7204 routers. Two subinterfaces with vlans were configured as follows.

interface GigabitEthernet3/1.500

description X

encapsulation dot1Q 500

ip vrf forwarding X

ip address x.x.x.x 255.255.255.252

!

interface GigabitEthernet3/1.510

description Y

encapsulation dot1Q 510

ip address y.y.y.y 255.255.255.252

Curently, one new equipment was placed in the middle of the equipments and need to change the

interface GigabitEthernet3/1.510 to no vlan.

Can I just do this?

interface GigabitEthernet3/1

description Y

ip address y.y.y.y 255.255.255.252

interface GigabitEthernet3/1.500

description X

encapsulation dot1Q 500

ip vrf forwarding X

ip address x.x.x.x 255.255.255.252

!

Thanks?

Jon Marshall · ‎03-05-2014

Irene

If you mean you do not want vlan traffic at all to go to gi3/1 but you do want vlan 500 traffic to go to the subinterface then no i can't see a way to do this because you still need a trunk link to the router interface which means it will be passing vlan traffic ie. subinterface gi3/1.500 is still expecting tagged vlan traffic.

If you just mean you don't want tagged vlan traffic for vlan 510 then with the older setup you could actually do what you are proposing ie. the gi3/1 main interface would receive non tagged traffic for vlan 510 assuming the trunk was configured with that vlan as the native vlan.

However i 'm not sure you can do this anymore.

But if you simply want vlan 510 to be untagged then you can modfiy your config as follows -

int gi3/1.510

encapsulation dot1q 510 native

which tells the subinterface that vlan510 is not going to be tagged. Obviously the trunk link needs to be configured with vlan 510 as the native vlan.

If this doesn't answer your question then please clarify.

Jon