When configuring Remote Access VPN, you have two options on how to assign IP addresses to connecting computer DHCP and Static Pool.
When you assign an address via DHCP, you can also provide DNS and WINS (and many other settings) configuration along with the IP address. This ensures that when the user needs to find out the IP address of a computer on the internal network, the user will use the internal DNS and WINS servers.
If you are running ISA Server 2006 Enterprise Edition and you have an array with two or more array members you cannot use DHCP, rather you must use Static Pool address assignment. You will need a separate unique address range for each array member. To ensure that users will still be able to perform name resolution of internal server we need to configure DNS and WINS server to be assigned along with the IP address from the static pools.
To manually configure DNS and WINS server entries:
Select Virtual Private Networks in the ISA Server Management Console, on the Task pane select Define Address Assignment.
Select Static address pool and click Add.
In the Server IP address Range Properties dialog box, select the ISA Server you will be assigning this address pool to and enter the starting and ending addresses. Note the address range must be a unique range of address in your network and it must not overlap with any existing networks already defined as a network in ISA.
To define DNS and WINS server entries click the Advanced button and on the Name Resolution dialog box, select Use the following DNS server addresses to specify the internal DNS server to be used by remote access connections. Select Use the following WINS server addresses to specify the internal WINS server to be used by remote access connections.
You have now configured ISA Server to use Static address pool while still maintaining name resolution for your remote access users.
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