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Bridging a VLAN...

Hi, I seem to have run into a brick wall and would appreciate any solution you can come up.

My client basically has two sites. Both sites have their own router and L3 switch. The routers are linked using multiple E1's bundled with MLPPP. Both L3 switches have multiple VLANs and are routed between sites using EIGRP.

Now this is where the fun stops. For some reason, the client needs to bridge a certain VLAN across the two sites in favor of running a relatively old application. This application, it seems, needs broadcast and other non-routable traffic to function on both sites. Furthermore, this bridged VLAN must still be able to see the other networks from both sites (ie. all L3 VLANs).

I have configured IRB before on a single box, but not across multiple L3 devices.

Any help on pointing me to the right direction is welcome.

Community Member

Re: Bridging a VLAN...


Use a TUNNEL. This will allow the passing of L2 traffic.


Community Member

Re: Bridging a VLAN...

Thanks for the reply. However, if it's not too much to ask, can you post a link about it? I tried doing a research on my own and I seem to end up looking at L2TP. But still, I fail to see how this is going to work.

The "bridged" VLAN I mentioned spans the two sites and they must be on the same IP subnet, as well as pass L2 traffic like they were all connected to a single VLAN.

Again, thanks.

Re: Bridging a VLAN...

Hi, oj88

I think the L2TPv3 techonology is quite suitable for your case. Here is a simlpe configuration example that might help you.



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