{{tag>systemd}}

====== systemd user service ======
1. Create user service in user's home directory ex. ///home/<app_user>/.config/systemd/user///

Example:
<code systemd>
[Unit]
Description=my npm app
After=network.target

[Service]
ExecStart=/usr/bin/npm start
WorkingDirectory=/home/debian/mynpmapp/
Restart=on-failure

[Install]
WantedBy=default.target
</code>

2. Enable service
  systemctl --user enable mynpmapp.service

3. From root enable lingering so that it persists over reboots and logouts

  loginctl enable-linger username

4. Use ''systemctl --user start|stop <servicename>'' to run service

===== TROUBLESHOOTING =====
<WRAP center round info 60%>
Below is only needed if you switch to the user from root or another user on the system. If you login via ssh as a user, PAM subsystem will set up the required variables.
</WRAP>


==== systemd --user does not work: 'Failed to connect to bus' ====
  apt install dbus-user-session

In .bashrc of the user put:

  export XDG_RUNTIME_DIR=/run/user/$(id -u)
  export DBUS_SESSION_BUS_ADDRESS="unix:path=${XDG_RUNTIME_DIR}/bus"

then logout and login again. If its still not working and you get na error

  Failed to connect to bus: No such file or directory

try rebooting the server.


====== Tested on ======
  * Debian 10

====== See also ======

====== References ======
  * https://wiki.archlinux.org/index.php/Systemd/User#Automatic_start-up_of_systemd_user_instances
  * https://serverfault.com/questions/841099/systemd-grant-an-unprivileged-user-permission-to-alter-one-specific-service
  * https://serverfault.com/a/1047069/353235
  * https://unix.stackexchange.com/questions/434494/how-do-i-setup-user-autostart-and-properly-configure-systemd-user-services/434647#434647