Boot Raspberry Pi from hard disk drive

First of all: hard disk drives use a lot of power. If your disk don't have its own power supply, you will need a usb split cable and a powerfull power supply (2A).


Usefull commands:
dmesg -- Display the system message buffer
parted -- Disk partitioning and partition resizing program
df -- Display free disk space
fdisk --DOS partition maintenance program


#Check that disk (sda) is found
sudo ls /dev

#Start fdisk
sudo fdisk /dev/sda

#Show old partitions
p<Enter>

#Delete old partitions
d<Enter>1<Enter>
d<Enter>2<Enter>
 
#Create partitions
n<Enter>(p)<Enter>(1)<Enter>(2048)<Enter> (Choose appropriate size for file area)


#Write table to disk and exit
w<Enter>

#Format sda1 to ext4
sudo mkfs.ext4 /dev/sda1


#Create dir and mount disk sda1
sudo mount /dev/sda1 /mnt

#Copy files from sd-card to disc
rsync -vax / /mnt

#Edit fstab file
sudo nano /mnt/etc/fstab

proc            /proc           proc    defaults          0       0
/dev/mmcblk0p1  /boot           vfat    defaults          0       2
/dev/sda1       /               ext4    defaults,noatime  0       0
/dev/sda2       none            swap    sw                0       0

#Unmount temp
sudo umount /tmp/sys /tmp/sd_sys

#Edit boot file
sudo nano /boot/cmdline.txt

dwc_otg.lpm_enable=0 console=ttyAMA0,115200 console=tty1 root=/dev/mmcblk0p2sda1 rootfstype=ext4 elevator=deadline rootwait

#Time for reboot!
sudo reboot

#Verify setup
df -h



#https://github.com/adafruit/Adafruit-Pi-ExternalRoot-Helper/blob/master/adafruit-pi-externalroot-helper