service --help | -h | --version
The SCRIPT parameter specifies a System V init script, located in /etc/init.d/SCRIPT. The supported values of COMMAND depend on the invoked script, service passes COMMAND and OPTIONS it to the init script unmodified. All scripts should support at least the start and stop commands. As a special case, if COMMAND is --full-restart, the script is run twice, first with the stop command, then with the start command.
service --status-all runs all init scripts, in alphabetical order, with the status command.
If the init script file does not exist, the script tries to use legacy actions. If there is no suitable legacy action found and COMMAND is one of actions specified in LSB Core Specification, input is redirected to the systemctl. Otherwise the command fails with return code 2.