Raspberry Pi

Command-Line Configuration

sudo raspi-config

Restart

sudo shutdown -r now

Get IP address

ifconfig

Install Jenkins on RasPi

Change Swap-File Size

sudo /etc/init.d/dphys-swapfile stop
sudo nano /etc/dphys-swapfile
sudo /etc/init.d/dphys-swapfile start

Re-issue ssh keys

Delete key-files and re-create them

sudo rm /etc/ssh/ssh_host_* && sudo dpkg-reconfigure openssh-server

Invalidate keys on client side if successfully connected before:

ssh-keygen -R {ip-address of raspi}

Show processes

ps aux | less

Unresponsive processess can then be stopped via

kill

Running a Python Script Automatically at Startup

Because the Pi can act as a standalone appliance, a common question is how to launch a Python script automatically when the Pi boots up. The answer is to add an entry to the /etc/ rc.local file, which is used for exactly this in the Linux world.

Just edit the file:

sudo nano /etc/rc.local

and add a command to execute your script between the commented section and exit 0. Something like:

python /home/pi/foo.py&

The ampersand at the end will run the script as a background process, which will allow all the other services of the Pi to continue booting up.

Autostart Desktop

mkdir /home/pi/.config/autostart
nano /home/pi/.config/autostart/clock.desktop

[Desktop Entry]
Type=Application
Name=Clock
Exec=/usr/bin/python3 /home/pi/clock.py

[Desktop Entry]
Type=Application
Name=airflow-webserver
Exec=xterm -hold -e '/home/pi/.local/bin/airflow webserver -p 8080'

OnScreen Keyboard


sudo apt-get update
sudo apt-get install at-spi2-core florence

Disable Screensaver

The easiest way to disable screen blanking in the Raspbian GUI is to install xscreensaver then configure it to disabled.

sudo apt-get update
sudo apt-get install xscreensaver

In the [Display Mode] tab, set like this - Mode: [Disable Screen Saver] Source

Install RSS-Reader

sudo apt-get install quiterss

or

sudo apt install akregator

ssh tips & tricks

https://smallstep.com/blog/ssh-tricks-and-tips/

Starting up a Raspi Zero W without a screen

SSH aktivieren: Um den SSH-Zugriff zu aktivieren, erstellen Sie im Verzeichnis der MicroSD-Karte (/boot) eine leere Datei mit dem Namen “ssh” (ohne Dateierweiterung).

WLAN aktivieren: Um den WLAN-Zugriff zu aktivieren, erstellen Sie im Verzeichnis der MicroSD-Karte (/boot) eine Datei mit dem Namen “wpa_supplicant.conf” (die Dateierweiterung hier ist .conf – kein .txt dahinter stellen, sonst funktioniert es nicht) mit folgendem Inhalt:

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev update_config=1

network={ ssid=”" psk="" } [Source](https://braspi.de/blogs/braspi-blog/raspberry-pi-ersteinrichtung-ohne-monitor-und-tastatur)

Installing Pi-Hole

curl -sSL https://install.pi-hole.net | bash

Source

Renaming the hostname

sudo nano /etc/hostname