More detail about scope for bridge configuration

guyome

Hello,

I'm trying to setup a openVPN in bridge mode so that the client subnet and the server subnet can talk. It is basically well described in the Howto for a routed VPN but not so detailed for bridge.

Currently the bridge is set up, the client subnet is 192.168.1.0/24 and the server subnet is 192.168.10.0/24 and openVPN works in a simple configuration ( a client that connects to the server). Given that the VPN is bridged clients have no problem to access computers on server side.

I'm trying thus to find out how to reach computers of the client subnet from the server subnet. Do someone have a more detail howto than the openVPN's one ? I did find nothing on google...

Thank.

janjust

what you're asking is not possible (from a networking point of view).

By bridging two networks, you "flatten" them: they're seen as one big network. Thus if you want to bridge both sides you would have to make both sides use the 192.168.0/24 subnet; but then you run into the problem that you have no way to detect conflicts - what happens if two hosts on either side use the same IP?

With some trickery (and full control over the assigned IPs on both sides) you could achieve what you want, but is that really worth the hassle? performance will be horrible (due to the nature of bridging, mostly).

guyome

Thank for the answer.

With some trickery (and full control over the assigned IPs on both sides) you could achieve what you want, but is that really worth the hassle? performance will be horrible (due to the nature of bridging, mostly).

I did so some days ago since I Have a full control over both network. It didn't works at all: I'm not sure that we can have a same network with two gateway without running into problem. But I'm not so aware of how works network.

what you're asking is not possible (from a networking point of view).

ok, but what means then the section of the howto called "Including multiple machines on the client side when using a bridged VPN (dev tap)". I just need to include the router of the client side into the VPN.