Systemd

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systemd is a suite of basic building blocks for a Linux system. It provides a system and service manager that runs as PID 1 and starts the rest of the system. systemd provides aggressive parallelization capabilities

Service File

[Unit]
Description=My Miscellaneous Service
After=network.target

[Service]
Type=simple
User=nanodano
WorkingDirectory=/home/nanodano
ExecStart=/home/nanodano/my_daemon --option=123
Restart=on-failure

[Install]
WantedBy=multi-user.target

Systemd Basics

Control whether service loads on boot

sudo systemctl enable my_service
sudo systemctl disable my_service

Manual start and stop

sudo systemctl start my_service
sudo systemctl stop my_service

Restarting/reloading

sudo systemctl daemon-reload # Run if .service file has changed
sudo systemctl restart my_restart

Or if working with a user service add –user flag

systemctl --user restart my_user_service

Cheking the logs

See if running, uptime, view latest logs

sudo systemctl status
sudo systemctl status my_service

Or for a user service

systemctl --user status my_service

See all systemd logs

sudo journalctl

Tail logs

sudo journalctl -f

Show logs for specific service

sudo journalctl -u my_daemon

For user service

journalctl --user-unit my_user_daemon

Unit Types

simple Default option, service has to be started immediately. This process must not fork
fork Service is considered to have started when process forks and the parent has exited
oneshot Executes a single job and executes, use RemainAfterExit = yes to keep service as active