When a DHCP server is installed and scopes are created in it it does not only assigns the IP addresses to the client computers but it also provides the machine with some other information which is helpful in communicating with other machines within the network and outside. IP address of DNS server and the default gateway can be a good example for this. During scope configuration if any administrator has not opted to configure additional settings for the scope he needs to manually do so after the scope is successfully created. As an administrator of a DHCP server in Windows server 2008 if you want to configure default gateway you need to follow the steps given below:
1. Make sure that you are logged on to Windows server 2008 with the administrator privileges and DHCP server and its scope is already configured.
2. Open DHCP snap-in and expand the name of the server to get IPv4 tree.
3. Expand the tree and expand the available scope.
4. Right click on Scope Options and from the available menu click on Configure Options.
5. On Scope Options box locate and check 003 Router checkbox.
6. Under IP address section type the IP address of the default gateway and click on Add button.
7. Click on Ok button to save the changes.
8. If required restart DHCP service to make the changes take effect.