Article ID: 171789 - View products that this article applies to.
This article was previously published under Q171789
When you run Nslookup from a command prompt on your Microsoft Windows NT 4.0 Domain Name Service (DNS) server, you receive the following error message:
Where x.x.x.x is the IP address of your DNS server.
**** Can't find server name for address x.x.x.x: Non-existent domain
**** Default server is not available
Default Server: UnKnown
NOTE: This problem may occur with other applications as well.
There is a missing or mis-configured PTR record for your DNS server in your reverse lookup zone. The DNS Manager does not automatically create a PTR record for your DNS server, even though it may automatically create an "A" record in your forward zone.
To resolve this problem, perform the following steps:
For additional information, please see the following articles in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/166753/EN-US/ )Microsoft DNS Server Reverse Lookup Error Adding Host Record
(http://support.microsoft.com/kb/162842/EN-US/ )DNS with "WINS Reverse Lookup" Fails with Multiple IP Addresses
Microsoft has confirmed this to be a problem in Windows NT version 4.0. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.
You can view the properties of an "A" record by right-clicking on it and then clicking Properties. When the above problem is encountered, the "A" record properties will have a check in Update Associated PTR Record. This seems to indicate that the PTR record has been created and is active, however, it is not true.
The reverse lookup zone is a database file that is used to allow a client, or resolver, to provide an IP address and request a matching host name. This file contains an SOA record and NS records similar to other DNS database zone files. It also contains pointer records.
This DNS reverse lookup capability is important because some applications provide these capabilities to implement security based on the connecting host names. Nslookup is one of these utilities.