My Client has a Draytek Vigor 2955. We currently have an IPSEC VPN running between out two sites. However, the VPN will only establish if I specify their whole network at the other end as available (192.x.x.x 255.255.255.0). As much as I like having access to his whole network, I can see this causing problems down the line. I am now setting up a second VPN to their failover site, and this time they have specified 10.x.x.x. 255.255.0.0. This does conflict with another customer, but I am looking through the user manual to try and help them, and I can't see whereabouts in the configuration they would go to limit the number of servers I can see.

If anyone knows where this elusive configuration is it would be highly appreciated.