Buster Ts-7840 image backup

To create backups / restore images, it is recommended to first boot to USB. A disk should not be backed up or written while it is used to boot.

If your image is a single partition it can be backed up as a tar file. This allows the media to easily expand to any disk size.

Create a backup tar

mkdir /mnt/emmc
mount /dev/mmcblk0p1 /mnt/emmc/
tar -cJf /root/backup-of-image.tar.xz -C /mnt/emmc/
umount /mnt/emmc/

Write a tar image to the eMMC

sgdisk --zap-all /dev/mmcblk0
sgdisk -n 0:0:0 -t 0:8300 /dev/mmcblk0
mkfs.ext4 /dev/mmcblk0p1
mkdir /mnt/emmc
mount /dev/mmcblk0p1 /mnt/emmc/
tar -xf /root/backup-of-image.tar.xz -C /mnt/emmc/
umount /mnt/emmc/

The same steps work with SATA, using the SATA device seen in "lsblk". This will be /dev/sda or /dev/sdb depending on the drive.