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New Member

Bridge LAN to LAN

We've got two networks that are separated by several routers/layer 3 devices. For various reasons, we need to get these two networks to appear to each other as being on the same network and broadcast domain. I've thought about tunneling between the two networks using GRE or L2TP, but I could find no example configs. Can someone help me out or point me to some example router configs? We've got Cisco 2811s connected to each of the subnets we need to bridge together. Also, we are only running IP on each network. Thanks.

Hall of Fame Super Silver

Re: Bridge LAN to LAN

Bridging over GRE tunnels is not officially supported. You can enter the commands and the router will accept them. You may get bridged traffic to flow through the tunnel. Not supported does not necessarily mean it will not work but it does mean that unexpected things may happen and that Cisco does not promise that it will work and that if a problem does happen that Cisco is not under any responsibility to provide any fix. In that situation I would be reluctant to do this in a production environment.