Symptoms: While performing sh latest command the system stuck with an error message about installer.lock.
Beginning main installation.
Detected an installer lock file (/root/installer.lock).
Please be sure that an installer is not already running.
You can remove the installer.lock file using this command via ssh
rm -rf /root/installer.lock
This problem arises while installing cPanel when an installation running on the same server is present or if an installer.lock file is existing in your /home directory where you are trying to install the cPanel. You just need to remove the existing installer.lock file and re-run the command sh latest which will proceed the installation smoothly.