While using Linux server, you may get following email as :
IMPORTANT: Do not ignore this email. The hostname (server.domain.tld
resolves to. It should resolve to xx.xx.xx.xx. Please be sure to
correct /etc/hosts as well as the ‘A’ entry in zone file for domain.
Some are all of these problems can be caused by /etc/resolv.conf
being setup incorrectly. Please check this file if you believe
everything else is correct.
1. Login to your WHM Panel and scroll down the left hand side functions menu until you find the heading ‘DNS Functions’. Click on ‘Add an A entry for your hostname’. WHM will try to analyze your hostname and then present you with a button to click that says Add the entry, go ahead and click on that. WHM should automatically try to add the relevant A record for your hostname to the DNS zone present on your system.
2. Login to your server via SSH and run the following command:
root@webhostprotocol [~]# /scripts/ipcheck
This command will send you an email immediately if your settings are still incorrect.
3. Hopefully that worked, but if not, we should go ahead and edit your /etc/hosts file just in case. Login to your system via SSH. Use your favorite text editor to make sure that your /etc/hosts file looks something like this.
root@webhostprotocol [~]# cat /etc/hosts
xx.xx.xx.xx server.domainname.com server
5. Use your preferred method of checking for the message again. Has it returned? Are you sure that your server is using the proper resolvers? Make sure that your /etc/resolv.conf has the following within.
6. If you still continue to receive the alert message even if hostname is resolving to your server IP, disable the IP DNS check option in WHM.
WHM >> Main >> Server Contacts >> Contact Manager “IP Address DNS Check”
NOTE: If the hostname is resolving properly to your server, it is safe to ignore/disable these alerts. It is not going to effect the working of your server/websites in any ways.