[H-GEN] verifying Burnt CDs

bob parker bob_parker at dodo.com.au
Tue Dec 24 09:45:20 EST 2002


[ Humbug *General* list - semi-serious discussions about Humbug and     ]
[ Unix-related topics. Posts from non-subscribed addresses will vanish. ]

On Tue, 24 Dec 2002 14:46, Matthew Taylor wrote:
> just checking if I have missed obvious method of checking CD burns.
>
> I have been using the attached simple script, in short
>
> burn iso image using cdrecord
> mount cd
> make iso image using mkisofs
> check iso image md5sum against md5sum of original iso image.
>
> another method I found below
>
> mount burnt cd
> df /mnt/cdrom
> dd if=/dev/cdrom bs=2048 count=[number of blocks from above command] |
> md5sum
>
> This should produce a md5sum to match the md5sum of the original iso image.
>
> I could swear previous CD's burnt using this method validated OK,
> recently this does not appear to be the case, despite slower CD burn
> rates and various CD blanks in a new CD Burner.
>
> then there's the 'linux mediacheck' option from the linux boot image.
>
> but on the CD's I've produced I get a message informing me the CD does
> not include a md5sum for checking.
>
> any ideas? what do others use for checking CD's against iso images?

This is what I am doing using Debian Woody.

mount -r -t iso9660 cd.iso -o loop /mnt
find /mnt/ -type f -print | xargs md5sum | cut -d ' ' -f 1 | sort > sumsin

mount /cdrom/
find /cdrom/ -type f -print | xargs md5sum | cut -d ' ' -f 1 | sort > sumsout

diff sumsin sumsout

The sort may not be necessary in all cases, I think I had to use it
to check the iso after I had created it using `cat /dev/cdrom > cd.iso`
during a cd copy.

HTH
Bob







--
* This is list (humbug) general handled by majordomo at lists.humbug.org.au .
* Postings to this list are only accepted from subscribed addresses of
* lists 'general' or 'general-post'.  See http://www.humbug.org.au/



More information about the General mailing list