Linux systemctl Command

The systemctl command is used to introspect and control the systemd system and service manager in Linux. It allows you to manage services, check their statuses, and perform various administrative tasks.

Common Options

• start: Start a service.
• stop: Stop a service.
• restart: Restart a service.
• status: Check the status of a service.
• enable: Enable a service to start at boot.
• disable: Disable a service from starting at boot.
• is-active: Check if a service is active.
• is-enabled: Check if a service is enabled.
• list-units: List all loaded units.

Examples

Start a Service

To start a service, use the following command:

systemctl start nginx

Stop a Service

To stop a service, use:

systemctl stop nginx

Check the Status of a Service

To check the status of a service:

systemctl status nginx

Enable a Service

To enable a service to start at boot:

systemctl enable nginx

Disable a Service

To disable a service from starting at boot:

systemctl disable nginx

Restart a Service

To restart a service:

systemctl restart nginx

Check if a Service is Active

To check if a service is active:

systemctl is-active nginx

List All Loaded Units

To list all loaded units:

systemctl list-units

Check if a Service is Failed

To check if a service has failed:

systemctl is-failed nginx

Check all the failed services

To check all the failed services:

systemctl --failed

Check the list of all unit files

To check the list the unit of all files:

systemctl list-unit-files

Check the list of all unit temprory

To check the list the unit of all files:

systemctl list-unit-files --type=service

Check the list of all unit files with their status

To check the list the unit of all files with their status:

systemctl list-unit-files --type=service --state=enabled

Masking

To prevent a service from being started, even manually, you can mask it:

systemctl mask nginx

This creates a symlink to /dev/null, effectively disabling the service.

Unmasking

To unmask a service, use:

systemctl unmask nginx