We have a server which is windows 2008 running on a VPS with a single public IP address.
I've configured the firewall to allow IPSEC VPN connections to be established with our Draytek routers at remote sites, and the VPS has it's private IP address added as an alternate IP address on the NIC.
From the end locations (192.168.160.x), I can ping the internal IP address of the VPS 192.168.180.10 without any problem, however any ping from the VPS isn't routed correctly through the VPN unless I set the source flag.
So ping 192.168.160.10 fails to work (pathping shows that it's going out through the public IP rather than choosing the VPN) but "ping -S 192.168.180.10 192.168.160.10" works exactly as intended.
Have tried to set up a static route, but this fails as there's only one interface to pick from. Also tried adding the private IP address of the server via loopback adapter, but I then can't get any traffic to the internet using ping -S 192.168.180.10 18.104.22.168 (for example).
Does anyone have any recommendations to get Win2008 to set the source IP correctly for the tunnel connections ?