update-rc.d:tldr:384f9

This command is used to remove the MySQL startup script from the system's init system.

Let's break down the command into its components:

• update-rc.d: This is the command used to update the runlevel information of the system's services or scripts. It is typically used to add or remove services from the startup process.

• -f: It stands for "force" and is used to forcefully remove the specified service. If this flag is not used, the command would prompt for confirmation before removing.

• ${mysql}: This is a placeholder for the name of the service or script being removed. In this case, it represents the MySQL service.

• remove: This is the keyword used to instruct the update-rc.d command to remove the specified service. It indicates that the MySQL service should no longer start automatically during the system startup process.

In summary, the command update-rc.d -f ${mysql} remove is used to forcefully remove the MySQL service from the system's startup process.