gconcat/gbde DVD encryption problem

[RW]

On Monday 18 December 2006 14:28, Pawel Jakub Dawidek wrote:
> On Mon, Dec 18, 2006 at 01:22:13PM +0000, RW wrote:

> > # gbde attach /dev/concat/datadvd
> > Enter passphrase:
> > gbde: Attach to concat/datadvd failed: could not access consumer
> >
> >
> > The same problem exists on a newly created disk, so it probably not
> > corruption. And if I copy the two file to hard disk it works.  It just
> > seems to be a problem when they are on the DVD.
> >
> > Any ideas on how to fix this. I'm not particularly bothered about the
> > existing disks, but I'd like to create some new ones.
>
> The problem is because gbde(4) tries to open provider read-write, which
> is not possible with CD-ROMs. You can work-around it by doing:
>
> 	(insert 1st CD)
> 	# dd if=/dev/acd0 of=/dvdrw/d1 bs=1m
> 	(insert 2nd CD)
> 	# dd if=/dev/acd0 of=/dvdrw/d2 bs=1m
> 	# mdconfig -a -f /dvdrw/d1 -u 31
> 	# mdconfig -a -f /dvdrw/d2 -u 32
> 	# gconcat create datadvd /dev/md31 /dev/md32
> 	# gbde attach /dev/concat/datadvd

Actually there are no CDs involved, it's a DVD-R with two big files on it, to 
work around the 2GB filesize limit on ISO 9660 filesystems.

I'm aware that I can work around it by copying the files to a  hard disk, but 
two years ago this worked with the data on the DVD without any problems.