I sometimes forget the syntax 🙂 Here is a reminder from how to backup RPidd if=/dev/sdx of=/path/to/image dd if=/dev/sdx | gzip > /path/to/image.gz Where sdx is your SD card. To restore the backup dd if=/path/to/image of=/dev/sdx when compressed: gzip -dc /path/to/image.gz | dd of=/dev/sdx