VPN Clients - Routing Back to Them?

[blyxx86]

Hello everyone,

I'm setting up an Intranet messenger on our computers in the office to let everyone talk quickly. The application uses UDP broadcasts to discover who is online. Internally this works just great.

The problem is with VPN clients. I've tried using both OpenVPN and Microsoft's VPN services. They can connect, get an IP and connect to every device in the network, but the UDP packets don't seem to make it to any of the other clients to say they're online.

For example. VPNStation1 connects to the VPN, gets an IP of 192.168.101.45. It can ping Workstation1(19 2.168.101.225), Workstation2(19 2.168.101.2), but the reverse is not true.

I dont see any logs in my firewall saying that they are being blocked, and both computers have Windows firewall disabled.

For some reason I think this is due to the gateway IP address given to VPNStation1? It connects to a local IP and I believe gets NAT'd.

Anyone have any idea on this one?

I imagine there are plenty of workspaces out there where an internal computer is able to connect to the VPN'd computer, but I don't know how to get that figured out.

Any help would be appreciated.

Thanks!
Kyle

[blyxx86]

UPDATE:

I was able to get the path back to the VPN'd computer working with OpenVPN by adding a static route to the computer on the internal LAN and using the IP of the OpenVPN gateway as the gateway IP.

route add 10.79.129.0 mask 255.255.255.0 192.168.101.5

However I'm still running into issues with the application since it uses simple broadcasts to find other clients.

Any suggestions?

[blyxx86]

Update #2:

It looks like this is an issue with UDP Broadcasts not traversing through the VPN client/gateway.

Is there a way to get it so that these UDP broadcasts get forwarded?

[sicarie]

Apologies - I got caught up with stuff around Christmas and wasn't able to login.

What is the make/model of the VPN client/gateway? (ie, what layer device is it? Does it allow that traffic?)