Sometimes inside WHM when clicking the “change hostname” link or by running the following command:
you may get presented with the following error message:
"Your previous attempt to change the hostname is still running. Please wait until it completes"
This happens when the server has attempted to change the hostname but the result has not been completed correctly. This could be because the server rebooted or your server's Kernel might be outdated.
You should first check your Kernel version and update it to the latest version. Next, cPanel stored a “lock” file in the application-locks folder. Remove it with the below command:
rm -rf /var/cpanel/.application-locks/UpdateHostname
If you updated your Kernel now is the time to reboot your system but if you made no changes to the Kernel you can now try to set the hostname from WHM and by clicking the “change hostname” link or from an ssh console whilst logged in as the root user using the below command:
Remember, your hostname needs to be an FQDM which means it should have two “.” in it. for example, server.yoursite.com would be acceptable but just server would not be.