DNS on Windows Server 2003, 3rd Edition

Can’t Look Up Local Name

The first thing to do when a program like telnet or ftp can’t look up a local name is to use nslookup to try to look up the same name. When we say “the same name,” we mean literally the same name—don’t add a domain name and a trailing dot if the user didn’t type either one. Don’t query a different name server than the user did.

As often as not, the user mistyped the name or misunderstood how the search list works and just needs direction. Occasionally, you’ll turn up real host configuration errors, such as a mistake in the resolver configuration (e.g., the wrong IP address for a name server). You can check for errors like this using nslookup’s set all command.

If nslookup points to a problem with the name server, rather than with the host’s configuration, check for the problems associated with the type of name server. If the name server is the primary master for the zone but it doesn’t respond with data you think it should:

• Check that the zone or zone datafile contains the data in question.

• Ensure that the domain names in the records are correct (problem 6).

If the name server is a secondary server, you should first check whether or not its master has the correct data. If it does, and the secondary doesn’t:

• Make sure you’ve incremented the serial number on the primary (problem 1).

• Look for a problem on the secondary in updating the zone (problem 4).

If the primary doesn’t have the correct data, of course, diagnose the problem on the primary.

If the problem ...