To save space, you can compress data produced by dd with gzip, e.g.:
dd if=/dev/your-flash-drive | gzip -c > /home/username/image.img
You can restore your disk with:
gunzip -c /home/username/image.img.gz | dd of=/dev/your-flash-drive
Unfortunate about the space.
DD should accurately capture the bit state of an unmounted drive. Best not to dd
a live filesystem
as it can corrupt files since the program has no understanding of the file-system activity that may be going on, and makes no attempt to mitigate it. If a write is partially underway, you will get a partial write.
How big is u flash drive?
---------- Post added at 01:58 PM CST ---------- Previous post was at 12:48 PM CST ----------
Partimage backs up data only.
yum install partimage
see here http://www.psychocats.net/ubuntu/partimage
for how to
or try clonzilla