Backup TO internal Flash


How can i perform a backup (i. e. image) of TO complete internal Flash?

Theoretically like this:

mount a large enough USB device with filesystem supporting large files like ext4
mount -r -o remount /dev/mmcblk0p1 /
dd if=/dev/mmcblk0 of=/mnt/myusbdev/omnia.image bs=64k

Be careful with if= (input file) and of= (output file) options so that you have correct device in those. For example of=/dev/mmcblkX would overwrite the flash instead of reading it and might crash the running system.

That is for reading the large flash device. There is also smaller flash device that contain for example boot images.