iknowright/raspberry-pi-university

Raspberry Pi usage at full extend.

Raspberry Pi University

Raspberry Pi usage at full extend.

Contents below are the work I have been on Raspberry Pi over these 3 years. I can't quantify the afford I put on this tiny little chip, but it'd been very fun for me. Hope you guys like it. Enjoy!

Table of Contents

• Prerequisites
• General settings
• Camera
• WiFi Dongle
• Remote Access (incl. advanced)
• 4G Internet Connection
• Mesh Network
• Continuous Integration
• RPi Management
• Real Life Example

Prerequisites

This workthrough is targetted for users using Raspberry Pi 3 or 4 with minumin OS installed (Command Line Interface Mode).

General Settings

WiFi Setting

There are two ways you can connect your pi with wifi.

First, via sudo raspi-config

• sudo raspi-config -> Network Options -> wifi -> {Enter your ssid} -> {enter your passphrase}

Second, via /etc/wpa_supplicant/wpa_supplicant.conf file

1. with your favorite editor go into file with sudo vim /etc/wpa_supplicant/wpa_supplicant.conf
2. append your WiFi info below as:

   ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
   update_config=1
   country=TW
   
   
   network={
       ssid="{your wifi ssid}"
       psk="{your wifi passphrase}"
   }
   

3. save the file
4. if you are going with this method, make sure you follow this command: sudo wpa_cli reassociate to make the new configured wifi works. Otherwise, reboot RPi with sudo reboot. Your wifi will be now set.

Interface Setting

• To use camera: sudo raspi-config -> Interface Options -> Camera -> Enable -> OK
• To use SSH: sudo raspi-config -> Interface Options -> SSH -> Enable -> OK

Camera

Befote started this make sure you have the settings right, follow the Interface Option for Camera in General Settings to enable camera interface. Which is sudo raspi-config -> Interface Options -> Camera -> Enable -> OK.

Remotely connect to RPi

Simple SSH

To make RPi accept ssh connections, make sure you enable the settings for ssh in sudo raspi-config, as mentioned in General Settings.

Over LAN

Fire up ifconfig

Over WLAN

Reverse SSH-Tunnel

AutoSSH + systemd to consistantly etablish revse ssh tunnel to server.

overview:

requirements:

• autossh
• ssh keygen (for password-less ssh)

setup:

• remote server
  • username
  • host ip
  • ssh keypem
  • port to reverse

[Unit]
Description=AutoSSH tunnel service Remote port {reverse-port} to local 22
After=network.target

[Service]
Environment="AUTOSSH_GATETIME=0"
ExecStart=/usr/bin/autossh -o StrictHostKeyChecking=no -o "ServerAliveInterval 10" -o "ServerAliveCountMax 3" -i /home/pi/{remote-server}.pem -N -R {reverse-port}:localhost:22 {remote-server-username}@{remote-server-host/ip}

[Install]
WantedBy=multi-user.target

Shellhub

ShellHub is a modern SSH server for remotely accessing Linux devices via command line (using any SSH client) or web-based user interface. It is intended to be used instead of sshd.

Server: A server with Static Public IP

Client: Your RPi with internet access

4G Internet Connection

I was luckily enough to ever worked on the 4G connection on RPi. The internet connection for 4G is supported by Waveshare SIM7600-T 4G HAT .

Official Wiki: SIM7600X 4G & LTE Cat-1 HAT

The workable way to use this module is by using the Qualcomm QMI-CLI tool to make the 4G connect to the internet. I tested the PPP method but failed multiple times until I found qmicli utils.

Here is how you setup for 4G connection:

1. Plug the 4G HAT in and wire the module as below
2. Install packages
3. Disable WiFi at boot option
4. Search your ISP / Carrier APN
5. Setup and run connection script

Resources: here

Mesh Network