Using IP Addresses to Avoid Name Resolution Issues
Applies To: Windows Server 2008, Windows Server 2008 R2
When you configure a demand-dial interface for a dial-up calling router, you provide the phone number of the answering router with which this router establishes a connection. In this case, name resolution is not an issue.
For VPN connections, however, the corresponding entry on the demand-dial interface is the destination address of the answering router. In this case, name resolution can be an issue, because you can provide either the Domain Name System (DNS) name or the IP address of the answering router. Microsoft recommends that you provide the IP address rather than the answering router’s DNS name when you configure a demand-dial interface so that resolution of the name to the IP address by means of a DNS or Windows Internet Name Service (WINS) server is not needed.
If you do use names for demand-dial interfaces, make sure that an appropriate DNS record exists on the DNS server that hosts the public namespace that is visible to Internet users and computers, or on the DNS server of your ISP, so that the DNS names of your answering routers can be resolved.