Create and restore a compressed image of a disk
The whole disk (SD-card) is read, piped through gzip for compression and written to the ouput file image.gz.
dd if=/dev/mmcblk0 bs=1M | gzip --stdout > ./image.gz
gunzip --stdout image.gz | dd of=/dev/mmcblk0 bs=1M
- both commands require root privileges
- be very careful to choose the right device when restoring!