Add the following to the file:
[Unit]
Description=Virola Server
[Service]
WorkingDirectory=/home/virola
User=virola
ExecStart=/usr/bin/virola-server --listen HOST:PORT --storage-dir ./storage
StandardOutput=append:/home/virola/virola-server.log
StandardError=append:/home/virola/virola-server.log
Restart=on-failure
ExecStartPost=/bin/sh -c 'umask 022; pgrep -f virola-server > /home/virola/virola-server.pid'
[Install]
WantedBy=multi-user.target
where
HOST
is the IP you've chosen for the Virola server
PORT
is the port you've chosen for the Virola server