Backing up or restoring from a CF card, usb stick or similar using dd

 The basic format of the commands are as follows;

dd if=/dev/sdb of=/tmp/backup-file

dd if=/dev/backup-file of=/dev/sdb

where /dev/sdb is the CF card or other portable storage device and /tmp/backup-file is the backup file.

NOTE: We are using /dev/sdb and NOT /dev/sdb1 as we'd possibly expect.

The first command creates the backup, the second, the restoration.