systemctl command

Control the systemd system and service manager.

Overview

systemctl is a command-line utility used to control and manage the systemd system and service manager. It allows users to start, stop, restart, enable, disable, and check the status of system services. It's the primary tool for interacting with systemd, which is the init system and service manager for most modern Linux distributions.

Options

status

Show the runtime status of one or more units

$ systemctl status nginx
● nginx.service - A high performance web server and a reverse proxy server
   Loaded: loaded (/lib/systemd/system/nginx.service; enabled; vendor preset: enabled)
   Active: active (running) since Mon 2025-05-05 10:15:30 UTC; 2h 30min ago
     Docs: man:nginx(8)
  Process: 1234 ExecStartPre=/usr/sbin/nginx -t -q -g daemon on; master_process on; (code=exited, status=0/SUCCESS)
  Process: 1235 ExecStart=/usr/sbin/nginx -g daemon on; master_process on; (code=exited, status=0/SUCCESS)
 Main PID: 1236 (nginx)
    Tasks: 2 (limit: 4915)
   Memory: 3.0M
   CGroup: /system.slice/nginx.service
           ├─1236 nginx: master process /usr/sbin/nginx -g daemon on; master_process on;
           └─1237 nginx: worker process

start

Start (activate) one or more units

$ sudo systemctl start nginx

stop

Stop (deactivate) one or more units

$ sudo systemctl stop nginx

restart

Restart one or more units

$ sudo systemctl restart nginx

reload

Reload one or more units

$ sudo systemctl reload nginx

enable

Enable one or more units to be started at boot

$ sudo systemctl enable nginx
Created symlink /etc/systemd/system/multi-user.target.wants/nginx.service → /lib/systemd/system/nginx.service.

disable

Disable one or more units from starting at boot

$ sudo systemctl disable nginx
Removed /etc/systemd/system/multi-user.target.wants/nginx.service.

is-active

Check whether units are active

$ systemctl is-active nginx
active

is-enabled

Check whether units are enabled

$ systemctl is-enabled nginx
enabled

list-units

List loaded units

$ systemctl list-units
UNIT                                      LOAD   ACTIVE SUB     DESCRIPTION
proc-sys-fs-binfmt_misc.automount         loaded active waiting Arbitrary Executable File Formats File System
sys-devices-pci0000:00-0000:00:02.0-drm-card0-card0\x2dDP\x2d1-intel_backlight.device loaded active plugged /sys/devices/pci0000:00/0000:00:02.0/drm/card0/card0-DP-1/intel_backlight
sys-devices-platform-serial8250-tty-ttyS0.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS0
...

--type=TYPE

List units of a specific type

$ systemctl --type=service
UNIT                               LOAD   ACTIVE SUB     DESCRIPTION
accounts-daemon.service            loaded active running Accounts Service
apparmor.service                   loaded active exited  AppArmor initialization
apport.service                     loaded active exited  LSB: automatic crash report generation
...

daemon-reload

Reload systemd manager configuration

$ sudo systemctl daemon-reload

Usage Examples

Checking the status of a specific service

$ systemctl status ssh
● ssh.service - OpenBSD Secure Shell server
   Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled)
   Active: active (running) since Mon 2025-05-05 09:45:23 UTC; 3h 10min ago
  Process: 1122 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=0/SUCCESS)
 Main PID: 1123 (sshd)
    Tasks: 1 (limit: 4915)
   Memory: 5.6M
   CGroup: /system.slice/ssh.service
           └─1123 /usr/sbin/sshd -D

Restarting a service and checking its status

$ sudo systemctl restart nginx && systemctl status nginx
● nginx.service - A high performance web server and a reverse proxy server
   Loaded: loaded (/lib/systemd/system/nginx.service; enabled; vendor preset: enabled)
   Active: active (running) since Mon 2025-05-05 13:05:45 UTC; 2s ago
     Docs: man:nginx(8)
  Process: 5678 ExecStartPre=/usr/sbin/nginx -t -q -g daemon on; master_process on; (code=exited, status=0/SUCCESS)
  Process: 5679 ExecStart=/usr/sbin/nginx -g daemon on; master_process on; (code=exited, status=0/SUCCESS)
 Main PID: 5680 (nginx)
    Tasks: 2 (limit: 4915)
   Memory: 2.8M
   CGroup: /system.slice/nginx.service
           ├─5680 nginx: master process /usr/sbin/nginx -g daemon on; master_process on;
           └─5681 nginx: worker process

Listing all failed services

$ systemctl list-units --state=failed
UNIT                  LOAD   ACTIVE SUB    DESCRIPTION
mysql.service         loaded failed failed MySQL Database Server
openvpn.service       loaded failed failed OpenVPN service

Tips:

Use Tab Completion

Systemctl supports tab completion for service names, making it easier to manage services without remembering exact names.

Check Service Logs

When troubleshooting services, use journalctl -u service-name to view logs specific to that service.

Mask Services

To completely prevent a service from being started (even manually), use systemctl mask service-name. This creates a symlink to /dev/null, making it impossible to start the service until it's unmasked with systemctl unmask service-name.

View Service Dependencies

Use systemctl list-dependencies service-name to see what other services a particular service depends on.

Manage System State

Beyond services, systemctl can manage system states like reboot (systemctl reboot), poweroff (systemctl poweroff), and suspend (systemctl suspend).

Frequently Asked Questions

Q1. What's the difference between `systemctl stop` and `systemctl disable`?

A. systemctl stop immediately stops a running service but doesn't change its boot behavior. systemctl disable prevents a service from starting automatically at boot but doesn't affect currently running services.

Q2. How do I make changes to a service configuration take effect?

A. After modifying a service file, run sudo systemctl daemon-reload to reload the systemd manager configuration, then restart the service with sudo systemctl restart service-name.

Q3. How can I see all available services?

A. Use systemctl list-unit-files --type=service to see all available service unit files and their states.

Q4. How do I create a custom systemd service?

A. Create a .service file in /etc/systemd/system/, then run systemctl daemon-reload to register it, and systemctl enable to enable it at boot.

Q5. What does "masked" status mean for a service?

A. A masked service is completely prevented from starting, either manually or automatically. It's a stronger form of "disabled" and is done by creating a symlink from the service file to /dev/null.

References

https://www.freedesktop.org/software/systemd/man/systemctl.html

Revisions

2025/05/05 First revision