OpenVPN Support Forum

I'm thinking of using openvpn to bridge two locations, but the configuration will have to be a bit odd. This is because one of the routers can't be configured, the client will have to function as a server, and ideally I don't want to add to the complexity of this network with an additional router.

Location A:

ADSL Modem-Router <-> Cisco router <-> Switch <-> Computers

(Cisco cannot be configured, and bridges to a "mother" network. Router at "mother" network cannot be configured either, also Cisco. ADSL Modem-Router and Computers can be fully configured)

Location B:

ADSL Modem-Router <-> Switch <-> Computers

Now, what I want to accomplish, is that at least one of the computers at location B will function as a computer which appears to be natively at location A.

Connecting both modem-routers to each other will not serve this purpose, as the important link is being made by the Cisco to the mother network, and this occurs one step later.

What I'm considering, is having a computer at location B operate an openvpn server, to which a computer at location A dials in. However, the point is of course to have a computer at location B operate as if it were natively at A. This includes receiving a dhcp address from location A.

Is this possible, or do I have to add a router behind the Cisco at location A?

yes this is possible: set up bridging on either end (I'd choose a PC on the cisco-side) and the PC from location B will appear as if it is on the same network as the others.

Bridging is explained in the OpenVPN HOWTO.