OLPC Firmware q4d09/fs-save
 How to make an image copy of internal storage of an XO-1.5 or XO-1.75
- determine the size of the internal storage, as shown by banner, usually 4GB,
- choose a USB flash drive, USB hard drive, or SD card that is larger than the internal storage size,
- filesystems add some overhead, so it might not be possible for a 4GB USB flash drive to hold the 4GB internal storage of an XO,
- choose ext2 or FAT filesystems for best compatibility with Open Firmware,
- choose a filesystem that has no critical data on it already, unless you already have copies of the data,
- use the fs-save command to make the image copy, for example:
ok fs-save u:\os.img
The screen will fill with grey blocks, and these will turn red indicating progress.
The image can be used for diagnosis. It may be converted to .zd for use by fs-update using the zhashfs program included in olpc-os-builder.