Cerealbot/rpi

I'm using an RPi 2 model B for this project. Here are my notes.

OS

Install

I'm just using Rasbian from the foundation's download page. I find Debian derivatives to be comfortable for projects such as this. You're welcome to use whatever distro you like.

I strongly recommend you follow some official guide for installing the OS if you're at all uncertain. The notes here are sparse and meant to make it faster for me to recover from a broken system.

Get the archive, extract the file. Should be along the lines of '2015-05-05-rasbian-wheezy.img'.

Flash it to the SD card: 'sudo dd if=2015...img of=/dev/sdX bs=4M'.

Configure things with the raspi tool that loads on first boot, then install your favorite packages. Mine are:

htop vim emacs byobu tmux build-essential bash-completion haproxy authbind

Set the time/zone

http://aryo.lecture.ub.ac.id/configure-timezone-settings-on-raspberry-pi-raspbian-wheezy/

By default, Rasbian has an ntp daemon running, but you may still need to select a timezone. Use tzselect to set the timezone, then echo the returned line into .profile.

for me, this means:

echo "TZ='America/Chicago'; export TZ" >> ~/.profile

Setup SSH

I really recommend setting up SSH keys. There are many good guides for this elsewhere.

Setup Git

There's really no need to do this, but I like having git handle passwords for me.

https://help.github.com/articles/caching-your-github-password-in-git/

git config --global credential.helper 'cache --timeout=3600'

Setup Byobu

• F1 allows you to set "log into byobu" to save some time while logging in.

• 'C-a a' will send C-a to /usr/bin/screen, so you can use screen within byobu to debug serial connections.

Recover SD Filesystem

Hypothetically, in a strictly theoretical sense, with no basis whatsoever to the real world and real people:

Say someone at your hackerspace is horsing around and trips the breaker that your Pi is powered from. Well if you're lucky, then you just walk over and reboot the sucker. Sometimes that doesn't work though, and the computer's little SD card has become corrupt. Rather than break out the backup that you totally have, let's try a quick recovery first.

First, remove the SD card and insert it into your computer. Make sure it is unmounted.

Test recovery:

sudo dd if=/dev/sdX2 of=pi_bkup.img
cp pi_bkup.img pi_bkup_recv.img
sudo e2fsck -fy pi_bkup_recv.img

You may have to run that last command twice, idk why. If the program successfully recovers the test image, you have two options:

• Flash this cured image file back to the partition it came from
• Try to directly recover the SD card, since you know it has a chance of working.

The second option is faster:

sudo e2fsck -ft /dev/sdX2

Reference thread

Good luck!