Starting LinBPQ from Systemd 

Ideal for Raspbian Buster.

Note in the above example there is a line referencing an application /usr/bin/screen. If you do not have the screen package installed, it is highly recommended to do so- screen will create a virtual console for linbpq, ideal for checking, diagnostics, debug/errors etc.

sudo apt install screen

When the node is running, while logged in as the user defined in the linbpq.service:

To attach:
screen -r linbpq
To detatch, press key combination sequence:
Ctrl-a d

Create the runbpq Script

I recommend running a script rather than the binary directly so that if you need to add TNC drivers or bind additional devices such as bluetooth TNCs, this would be the ideal place to put them In sequence.

#!/bin/bash
#
# Edit to reflect the directory location of linBPQ installation
cd /home/bpq/node
#
# Attempt to upgrade (if linbpq.new exists) on next restart
mv linbpq.new linbpq
./linbpq

Set execute and the correct USERID and GROUP permissions on the runbpq script AND linbpq binary. This will make it run with the correct user ID if at any point it is launched manually.

sudo chmod +x runbpq
chown <userid>:<groupid> runbpq linbpq
sudo chmod u+s runbpq linbpq

Upgrade preparation

IMPORTANT: If you drop an upgraded linbpq into the directory, you should name it linbpq.new and run the following commands on it to prepare it for when the linbpq service is next restarted (useful if running a node with a specific scheduled maintenance window). 

sudo chmod +x linbpq.new
sudo chown <userid>:<groupid> linbpq.new
sudo chmod u+s linbpq.new

Starting linbpq from systemd

Create the file linbpq.service with the following contents:

[Unit]
Description=LinBPQ
After=network.target
[Service]
Type=forking
WorkingDirectory=/home/bpq/node
Restart=always
User=bpq
Group=bpq
ExecStart=/usr/bin/screen -S linbpq -d -m /home/bpq/node/runbpq
#ExecStart=/bin/bash /home/bpq/node/runbpq
SyslogIdentifier=LinBPQ
[Install]
WantedBy=multi-user.target

Edit the ExecStart path to reflect the location of runbpq on your system.

Move linbpq.service into the /etc/systemd/system/ directory

sudo mv ./linbpq.service /etc/systemd/system/
cd /etc/systemd/system/

Then run

sudo systemctl daemon-reload
sudo systemctl enable linbpq.service

Which does this:

Created symlink /etc/systemd/system/multi-user.target.wants/linbpq.service → /etc/systemd/system/linbpq.service.

And that should be it. LinBPQ will now start from boot, and you have prepared a system to assist with future upgrades of the node binary.

Further tips

You can check your systemd startup sequence status issuing:

sudo systemctl status