Bridging two routers

tim_mccolgan · ‎01-17-2007

Curious to know the process on how to bridge two routers. In this case we have a 2821 and a 3600 we need to bridge in a location. The 3600 routes data currently and we're installing the 2821 to service/encrypt VoIP. I can honestly say I have no experience with bridging routers or the commands.

Any assistance would be wonderful. Thank you!

hitesharora · ‎01-18-2007

Hi,

You will need to disable 'ip routing' on the routers and enable the bridging protocol on the interfaces which you want to be bridged.

Rgds

tim_mccolgan · ‎01-18-2007

Thanks Rgds. I'm a little confused still:

If you have the new router, and want to bridge to the existing router, both ends need to have ip routing turned off? How does the data get over the ?T? with it turned off?

Also, any commands would help as well. Thank you again.

flitcraft33 · ‎01-18-2007

If I understand your question, I think you need to use IRB bridging on two interfaces on each router. you simply use the following config commands, (I have shamelessly used a Cisco provided example here);

bridge IRB

bridge 1 protocol ieee

then add the interfaces you want to bridge traffic to a bridge group.

For instance,

interface Ethernet0

no ip address

no ip directed−broadcast

bridge−group 1

interface Ethernet0

no ip address

no ip directed−broadcast

bridge−group 1

Will add the1 and 0 to a bridge group.

What's even cooler is that you can actually route to and from the bridge GROUP by giving it an ip address.

interface BVI1

ip address 10.10.10.1 255.255.255.0

no ip directed−broadcast

!

ip classless

ip route 10.10.30.0 255.255.255.0 10.10.20.2

!

bridge 1 protocol ieee

!−− This command enables the bridging on this router.

bridge 1 route ip

!−− This command enable bridging as well routing for IP protocol.

Hope this helps.

Dan Sichel

Ponderosa Telephone