Configuring dual uplink ports for LAN on a 3900 router?

[millerjw]

So I have this 3900 series router that only supports sub-interfaces.  I have a stack of switches that I would like to confure dual uplink's for redundancy.  Normally I just create my physical interfaces as trunks carrying the same vlans, and use interface vlans for the L3.  How do I configure this on this router that only supports L3 subinterfaces?

Thanks,

-J

[Dan-Ciprian Cicioiu]

Hi ,

i think that you can try bridging the subinterfaces, but i am not sure that the router will let you using the same dot1q tag on different interfaces.

HTH

Dan

[millerjw]

so you mean putting the interface in a bridge group and configuring the L3 on a BVI?

[Dan-Ciprian Cicioiu]

Yes , but my doubt is that the router will let you set the same tag on diferent subinterfaces ( that belongs to diferent phisical interfaces ).

Dan

[paolo bevilacqua]

Of course you can do that. .1Q tags don't have to be unique.

[Dan-Ciprian Cicioiu]

Yes Paolo , you are right.

Dan