11.10.2010
These methods implies that you created first a dvd image (.iso).
After burning, mount the DVD image somewhere on the disk:
# mount -o ro,loop -t iso9660 /path/to/file.iso /point/mounting
And then check with <i>diff</i>:
# diff -r /point/mounting /media/cdrom
Note: /media/cdrom could be different. Check your local settings (/media/…)
You simply compare the md5 sum for image and burned DVD:
# md5sum /path/to/file.iso 50dc0947340b855e28ba4f8c79202f9a /path/to/file.iso
For disk you should know the number of extents written. This number is outputed when you create the dvd image (by mkisofs or genisoimage). Example:
Total translation table size: 0 Total rockridge attributes bytes: 31270 Total directory bytes: 116736 Path table size(bytes): 1010 Max brk space used 42000 2062625 extents written (4028 MB)
And then md5sum on:
# dd if=/dev/cdrom bs=2048 count=2062625 | md5sum 2062625+0 records in 2062625+0 records out 4224256000 bytes (4.2 GB) copied, 517.057 s, 8.2 MB/s 50dc0947340b855e28ba4f8c79202f9a
You should avoid dd if=/dev/cdrom | md5sum because it will return wrong results (this includes also other bits of informations apart for iso image)
dvdisaster dvdisaster stores data on CD/DVD/BD (supported media) in a way that it is fully recoverable even after some read errors have developed. This enables you to rescue the complete data to a new medium.