Before we proceed, we need to add a second forest. You will need yet another Windows Server 2003 computer to proceed. Give this new server an IP address of 192.168.1.75 and a name of DCA . Be sure to set the computer's DNS server address to the same value as its IP address. After installing Server 2003, promote the server to domain controller status as as outlined in Chapter 2 using the following guidelines:
Create a new domain controller for a new domain
Name the domain piggy .wig
Create a new domain in a new forest
When asked, be sure to choose Install and configure the DNS server on this computer
Once your domain controller for the piggy.wig domain is configured, you have not only created a new domain, you have also created a new forest (albeit a forest of one domain and one domain controller). We now need to make sure that these two domains have common ground in which to resolve DNS namespaces.
On the new domain controller DCA in the piggy.wig domain, open the DNS administration tools located on Start ˆ’ > Administrative Tools .
Right-click the DCA icon on the left pane of the window and choose Properties . Click the Forwarders tab. This window allows you to specify specific domains that are not handled by the piggy.wig DNS server. For each of these domains, we can specify a DNS server in which to forward requests made by clients . Since each domain controller in all three domains in the guinea.pig forest are essentially copies of each other (due to replication), we can point the piggy.wig DNS server to any of the domain controllers in that forest (DC01, DC02, or DC03). Next to the DNS Domain field, click New and add type guinea.pig , hitting Enter . The name guinea.pig appears in the domain list.
Click guinea.pig once. Click once in the field labeled Selected domain's forwarder IP address list and enter the IP address of a DNS server in the guinea.pig domain. For this example, we use DC01's IP of 192.168.1.1 . Click Add .
Repeat this process for austin.guinea.pig and denver.guinea.pig, pointing both of those domains to DC01 (192.168.1.1). In addition to forwarding requests for all three domains to DC01, you can also add multiple DNS forwards for each domain. For example, if the DNS server DC01 in guinea.pig is down, we can direct the piggy.wig DNS server to try DC02. If DC02 is down, we could instruct piggy.wig to try DC03.
Clients in piggy.wig are now able to access objects in the guinea.pig forest. When all is said and done, you should see something similar to this screenshot. Click OK when finished:
On DC01 in the guinea.pig domain, add a forwarder to point DC01's DNS server to piggy.wig's DNS server. Do the same for DC02 and DC03. This way, clients in denver, austin, and guinea.pig are able to access objects in piggy.wig.