When accessing a computer on the Internet, you generally type in a domain name (such as www.raycomm.com) and your system translates it into an IP number (such as 188.8.131.52). As a rule, the translation from domain name to IP number proceeds without a problem. Heck, most of the time, you won't even notice that it happened. Occasionally, though, you'll come across an error message that says something like "failed DNS lookups." All that this message means is that the domain name server (probably on your Unix system) cannot match the domain name you provided to an IP number.
Code Listing 12.8. You can manually translate a domain name into an IP address using nslookup.
So, what do you do?
To match a domain name with an ip number using nslookup: