nautilus-cd-burner repeatedly creates coasters while cdrecord works perfectly

[Jaime]

Hi,

I've spent a few hours today trying to burn myself the hoary 5.04
release candidate x86 install cd, and I've found something a little odd.
Firstly, I've checked my downloaded copy of the iso file using md5sum
and it hashes to the correct value (c868ccfe958f85f3ef96c06f45707ad6) so
I'm happy that I've downloaded it ok. Running "isoinfo -d -i
hoary-rc-install-i386.iso" tells me that the logical block size is 2048
and the volume size is 305805, so I now know that I can check a burnt cd
by running:

dd if=/dev/hdc bs=2k count=305805 | md5sum

Then I've burnt the iso file on to a cdrw using nautilus-cd-burner (I
just right-clicked on the iso file and selected "Write to disk..."), and
everything seemed OK (there were no error messages issued)- when I
replace the ejected cd back in the drive, it gets automounted and
everything looks fine. Just to be certain, I do the following md5sum
check on the cd, and I get the following errors:

blah at poota:~/Desktop $ dd if=/dev/hdc bs=2k count=305805 | md5sum
dd: reading `/dev/hdc': Input/output error
8ceef06804031a060cc833878f83e814  -
305780+0 records in
305780+0 records out
626237440 bytes transferred in 230.479565 seconds (2717106 bytes/sec)
blah at poota:~/Desktop $

"Ah", I think, "media problems. OK, I'll just try cdrecord on the same
disk using the same burner, then...":

blah at poota:~/Desktop $ cdrecord blank=fast dev=/dev/hdc speed=10 \
padsize=63s -dao -pad -v -eject hoary-rc-install-i386.iso

blah at poota:~/Desktop $ dd if=/dev/hdc bs=2k count=305805 | md5sum
c868ccfe958f85f3ef96c06f45707ad6  -
305805+0 records in
305805+0 records out
626288640 bytes transferred in 167.843223 seconds (3731391 bytes/sec)
blah at poota:~/Desktop $


Just in case the problem using nautilus-cd-burner was a one-off, I then
repeated the same experiment twelve (12) times (six times for
nautilus-cd-burner and six times for cdrecord) and every time,
nautilus-cd-burner creates a coaster, and cdrecord works perfectly.


(I already know that I can do a file-level md5sum check using:
cd /media/cdrom
md5sum -c md5sum.txt
but the above still appears broken to me).


By the way, I've done all of this on an up-to-date warty machine.

I'm just about to put this into bugzilla against nautilus-cd-burner, but
I thought I'd post it here too.

Hope this helps someone else,

Jaime