Cloudninjakip / find-overlap

find-overlap.py is a command line tool which reads a file system (or any other data) and finds the overlapping range after an interrupted GParted resize/move

find-overlap.py

find-overlap.py is a command line tool which reads a file system (or any other data) and finds the overlapping range after an interrupted GParted resize/move.

Works by computing the MD5 hash of every block and finding blocks with a duplicate copy to identify the overlap size and location. Takes as long to run as reading the named device.

Example

# find-overlap.py --dump-hashes /tmp/hashes.txt -- /dev/sdb1
Block size: 1048576 bytes

Overlap of size 4096 blocks found.
Range [4321:8417) overlaps [8417:12513).
Original file system size was 16384 blocks.
Restore original file system with:
    dd if=INPUT bs=1048576 count=6369 of=OUTPUT
    dd if=INPUT bs=1048576 skip=10465 seek=6369 of=OUTPUT

Use of the --dump-hashes option is recommended as it avoids having to read the file system again if you need to re-run the command. See --read-hashes option. Also the dump file must be provided when users request help.