(my experience)it is more important to check to written data on cd...

[hkl8324]

than to only check the sha1/md5sum of the ISO file(s) on the HDD....

if you burn the CD at 52x or DVD at 16x...make sure you check the written data on cd....

(tick verifiy disc after burning in nero/k3b/whateveryouusetoburnyourcd/dvd)

[imdeemvp]

I always burn at 16x max and never have problems with iso's.

[tejas]

My burner supports upto 4x for CDs and 0x for DVDs.

I usually have no problem

And what I do is burn the CD. Then do
sha1sum /dev/cdrom

[komi]

i had big problems with burning the iso's on cd...
burned with 8x, and none of the 4 cd's were vailid (said the mediacheck)
i also tried burning them on an other computer, same result
i tried with cd-r and cd-rw, but it doesn't work.
my downloaded iso's were good!

so i put the iso's on my external usb2 hardrive, and installed it from there -> no problems

komi

[tejas]

I have a feeling you may have left multisession on by accident

That would change the md5sum, making it fail the media check

[komi]

hmm...
i just right-clicked on the iso file in nautilus and choosed "write to cd" from the contextmenu.

think there is no option for multisession, when i'm burning an iso file

[tejas]

OK, but K3B allows you to do that.

Anyway, did the CD and the image have the same md5sum (or sha1sum)?

Because something fishy is going on. Perhaps both burners are not working?

[komi]

Because something fishy is going on.

yes...

Perhaps both burners are not working?

with the second one, i burned a normal data cd with no errors...
so at least this one should be ok.

checking the cd's now, i hope this command was right???:

cat /dev/hdc | sha1sum -

[komi]

hmm.. result of first cd:

[komi@firecore ~]$ cat /dev/hdc | sha1sum -
cat: /dev/hdc: Input/output error
2d6769f66b4e41c93f508392dd76a7574fd899f2 -

[tejas]

That is very curious. This may be a clue. The sha1sum for a blank file is
da39a3ee5e6b4b0d3255bfef95601890afd80709

This is clearly not your sum. Hence, some part of your data is corrupted, but at least the beginnig of the CD is OK.

Try directly sha1sum /dev/cdrom (though it does the same thing)

[komi]

[root@firecore X11]# sha1sum /dev/hdc
sha1sum: /dev/hdc: Input/output error

/dev/hdc is my cdrom

[komi]

when I'm home again, I'll try this: http://www.fedorafaq.org/#mediacheck