Restore backup from an image

Step 1: Enter recovery mode

For instructions, look here and here

Step 2: Mount microSD-card

Mount your microSD card with the following command. Your SD-card needs to have at least 105GB of free space.

mount /dev/mmcblk0p1 /mnt

Step 3: Restore the backup

Execute:

dd if=/mnt/backup.img of=/dev/sda79 bs=1M

Note: This can take 40+ minutes. During this time, no progress is shown. If you would like to see progress, open a second telnet connection and execute watch -n5 'kill -USR1 $(pgrep ^dd$)', which will show progress (in the original telnet session) every 5 seconds.

Step 4: Unmount the memory card

Once the backup is finished, unmount the microSD-card with:

umoumt /mnt

Step 5: Exit recovery mode

For instructions, see here and here