Hey there! Let’s talk about running a service on system start in Raspberry Pi. This procedure is important if there are scripts needed to be called during system startup in Raspberry Pi.

* How to Run Service on System Start in Raspberry Pi
1. Create a new service file (also called Unit) in /lib/systemd/system/ using command below:
sudo nano /lib/systemd/system/test-service.service
2. Add the following text in the new service file and save it
Description=Test Service
After=multi-user.target
[Service]
Type=idle
ExecStart=/usr/bin/python /home/pi/test-python.py
[Install]
WantedBy=multi-user.target
3. Add read/write permission (if needed) to the service file using the following shell command:
sudo chmod 644 /lib/systemd/system/test-service.service
4. Now the service file has been defined, tell systemd to start it during the boot sequence:
sudo systemctl enable test-service.service
5. Reload the systemctl daemon
sudo systemctl daemon-reload
6. To test, reboot the Raspberry Pi:
sudo reboot
7. Check status of service
sudo systemctl status test-service.service
+ Other notes:
a. To disable, run command:
sudo systemctl disable test-service.service
b. Start/Stop/Restart unit file
sudo systemctl start test-service.service
sudo systemctl stop test-service.service
sudo systemctl restart test-service.servicee