Step1:Check the DNS server is configured on Client end or not
check in below file if name server is configured to proper DNS server or not
If the client is configured with proper DNS server follow to next step
Stpe2:Ping to DNS server ip address
If pinging is happening proceed with the next step.
Step3:So pinging is happening… then there is a communication path between Server-client, so we have to check weather DNS server is running or not. Here nmap can be used to check what ports opened on server.
this command will give you output what are the services running/ports opened on remote server, if DNS server is running and working fine means you can see DNS port(53) in the list of opened ports.
Step4:Now checking DNS server issue in deep
- Checking under whom the DNS server is register and its properties .
- Checking what server is used to resolve and some basic info.
- Checking who is resolving and what is resolving in details about DNS server.