example.service

# location: /etc/systemd/system/
[Unit]
Description = Example script that runs a shell script at boot
After       = syslog.target

[Service]
# make sure the shell script is executable (chmod +x $1)
# and it begins with a shebang (#!/bin/bash)
ExecStart   = /path/to/startup.sh

# In my example script I start a node server,
# So tell the serive how to kill it / reload.
ExecStop    = kill -INT `cat /run/node.pid`
ExecReload  = kill -TERM `cat /run/node.pid`

# In case if it gets stopped, restart it immediately
Restart     = always


# With notify Type, service manager will be notified
# when the starting up has finished
Type        = notify

# Since Type is notify, notify only service updates
# sent from the main process of the service
NotifyAccess= main

# systemd gets to read the PID of daemon's main process
# see ExecStop and ExecReload
PIDFile     = /run/node.pid

[Install]
# multi-user.target corresponds to run level 3
# roughtly meaning wanted by system start
WantedBy    = multi-user.target