This article will help you to how to manage services using the systemctl command for Systemd services. Systemd is a system and service manager for Linux-based operating systems for managing services. Systemd is more powerful and getting more popularity over older SysVinit. Most of newer release of the Linux-based operating system (eg: CentOS/Redhat 7, Fedora 25, Ubuntu 16.04) using Systemd as a default service management tool.

Before using the following example commands change <servicename> with your actual service name like httpd, mysql, apache2 or ssh.

Start or Stop Service:

Syntax:

$ sudo systemctl start <servicename>.service
$ sudo systemctl stop <servicename>.service
  • start: Used to start a stopped service
  • Stop: Used to stop a running service

Example:

$ sudo systemctl start ssh.service
$ sudo systemctl stop ssh.service

Restart or Reload Service:

$ sudo systemctl reload ssh.service
$ sudo systemctl restart ssh.service
$ sudo systemctl reload-or-restart ssh.service
  • Reload: Used to reload configuration of a running service
  • Restart: Used to restart (Stop/Start) a running service
  • reload-or-restart: Used to reload a service default, but if reload is not available for that service. It will restart it

Check Status of Service:

$ sudo systemctl status ssh.service
  • Status: Used to check current status of a service

Enable or Disable Service:

$ sudo systemctl enable ssh.service
$ sudo systemctl disable ssh.service
  • Enable: Used to enable service to start on system boot
  • Disable: Used to disable service to not to start on system boot

Check Enable/Disable Status of Service:

$ sudo systemctl is-active ssh.service
$ sudo systemctl is-enabled ssh.service
  • is-active: Used to check if service current service status
  • is-enabled: Used to check if service is enabled to start on system boot

Reference:
https://fedoraproject.org/wiki/SysVinit_to_Systemd_Cheatsheet