Systemd

Systemd is an init system that maintans a dependency tree to asynchronously load services.
It also includes facilities typically managed by other separate components (ex. logging, tmpfs mounts, ..).

Documentation

github	https://github.com/systemd/systemd
official docs	https://systemd.io/

Tutorials

writing systemd services	http://unix.stackexchange.com/questions/47695/how-to-write-startup-script-for-systemd
archwiki daemons	https://wiki.archlinux.org/index.php/Daemons

Locations

/etc/systemd/system/*.service	custom system-services
~/.config/systemd/user/*.service	custom user service files
/usr/lib/systemd/system/*.service	system-services from libs
/usr/lib/systemd/user/*.service	user-services from libs
/etc/default/	service configuration files
/run/systemd/generator/*
/etc/conf.d/*	environment files

Permissions

systemctl-journal

group members can journalctl without sudo

Notes

systemd usage

systemd journald

systemd service syntax

systemd timer syntax

systemd troubleshooting