DNS on Windows Server 2003, 3rd Edition

Finding IP Addresses

You’ll notice that we gave you a number of domain names of hosts that have ftpable software, and the mailing lists we mentioned include domain names. This should underscore the importance of DNS: see what valuable software and advice you can get with the help of DNS? Unfortunately, it’s also something of a chicken-and-egg problem: you can’t send email to an address with a domain name in it unless you’ve got DNS set up, so how can you ask someone on the list how to set up DNS?

Well, we could give you the IP addresses for all the hosts we mentioned, but since IP addresses change often (in publishing timescales, anyway), we’ll show you how you can temporarily use someone else’s name server to find the information instead. As long as your host has Internet connectivity and the nslookup program, you can retrieve information from the Internet namespace.

To look up the IP address for ftp.microsoft.com, for example, you could use:

C:\> nslookup ftp.microsoft.com. 207.69.188.185
            

This instructs nslookup to query the name server running on the host at the IP address 207.69.188.185 to find the IP address for ftp.microsoft.com and should produce output such as:

Server:  ns1.mindspring.com
Address:  207.69.188.185


Name:    ftp.microsoft.com 
Address: 207.46.133.140

Now you can ftp to ftp.microsoft.com’s IP address, 207.46.133.140.

How did we know that the host at IP address 207.69.188.185 runs a name server? Our ISP, Mindspring, told us—it’s one of their name servers. If your ...