N-central Help

KBA10015: DNS Service is Failed

Knowledge Base Article #: 10015
Applicable Versions: N-central 6.x, 7.x, 8.x, 9.x
Date Created/Updated: April 27, 2011


This article is to discuss common problems with the DNS service in N-central. The DNS Service is used to monitor name resolution using the device in question as the DNS server. If the device you are monitoring DNS on is not a DNS server then this will fail.

If this server is a DNS server, then try the below command to test the lookup of the IP and diagnose the issue.

  1. Log in to the Probe machine
  2. Click on Start, point to Run and type: cmd.exe and press <Enter>.
  3. Type: nslookup and press <Enter>.
    It will return with the default DNS server and a prompt ">"
  4. At the prompt type "server xx.xx.xx.xx" where xx.xx.xx.xx is the IP of the device in N-central
    It will return with the name and IP of the server you have chosen as the DNS server.
  5. Enter the URL you are looking to resolve in the N-central Service and press <Enter>

This will perform an NSLOOKUP on the target URL using the "server" you have specified (i.e. the IP of the device in N-central).

If this fails then this device is not responding to DNS requests from the probe machine and N-central has reported a "True" failure in this instance.

If this test is able to resolve the name please past the content of the CMD window into the case and inform the technician with a case comment.