How-To Technical

Raspberry Pi – Root FS on USB Thumb Drive

“We build too many walls and not enough bridges.” – Isaac Newton

Today I worked on resetting up my Raspberry Pi with a minimal image from Chris’s Digital Realm. I like this image because its very basic and does what one would want. Boot, and assigned an IP Address via DHCP, and best of all, fits on a 1GB SD Card. The rest is on you to install additional packages and updates. Thanks Chris, I love you work and has been helpful in jump starting my Raspberry Pi experience.

After a few setups and seeing how 1GB SD was not going to give me the space for all the packages I wanted installed, I started looking for a way to boot my Rasp~Pi and add additional storage.

To get this working I did the following:

1. I wrote the rasp~pi image (the one from Chris’ site) to a USB stick, instead of an SD card.
Sorry for not providing the direct link to the download; Please Chris’s site for that.

2. after that, plug your USB stick into your computer, copy all files files from USB stick into your SD card. I have found that you only need the following to boot: start.elf, loader.bin, kernel.img, config.txt, cmdline.txt, bootcode.bin which can fit even a 16MB SD card.

3. modify cmdline.txt, change the root=/dev/mmcblk0p2 to root=/dev/sda1 or root=/dev/sda1
in my setup I needed to change to root=/dev/sda2

— Additional Info —

1. Format your SD card to FAT16 before placing files on it. – I use gparted to do this
2. Feel free to remove the FAT16 partition from the USB Drive; You wont be using it.
3. Use gparted to give you more space on the root file system if you needed. The image will leave the rest of the space unused. I may do a write up on this later as I am thinking of adding a swap.

Hope this helped. Now plug in and boot up the root filesystem from the USB stick!