We currently use RAS on a server 2008 for VPN access to our network.
The problem is that the hosts connected to the network through that VPN can't resolve onsite names.
Ex: $remoteuser on $remotecomputer connects to corp VPN server. If $remoteuser tries to ping $onsiteserver using its hostname it fails. Pinging the servers IP works fine.
Clearly the client still uses its local DNS server (home router). So when $remotecomputer tries to resolve $onsiteserver the request gets to $remoteuser's home router, which just shrugs and sends the resolution request to the internet.
Is there any way to force the clients to use on-site DNS server for resolution (when they are connected to the VPN)
The name resolution issues wasn't related to which dns server was used, but rather that the RAS "DHCP" pool did not send DNS suffix info.
So while i couldn't ping "remoteserver" i could ping "remoteserver.contoso.local". I added the DNS suffix to the RAS DHCP and now it works fine.