red-phoenix
i just downloaded Mandriva linux and was quite happy playing around with the cool 3d desktop until i stumbled on this very nasty bug.
the kernel seems to like to trash DVD-R discs when it reads them as UDF file systems.
let me repeat this one slowly again, IF U HAVE A DVD-RAM DRIVE AND U ACTUALLY TRY TO READ A DVD-R DISC, THEN U ARE SIMPLY SCREWED!
it does this even to finalised multisession discs. by just mounting them, it kills the discs. the only thing that ISOBUSTER can recover would be the label of the drive, literally. plus, if if u use neroBuner's feature to "continue multisession" u will notice that the disc has a new crappy session of around 1 or 2 megs.
whatever was on the DVD is now gone.
i'm not sure about this, but this problem seems to only affects movie DVDs.
i lost around 6 movies to this, but i when tried an old mandrake 10.1 data dvd it was not damaged.
this also seems to affect only originally recordable DVDs like Princo or LG...
NORMAL DVDS, the ones u find in Virgin or the Malysian bootlegged ones do not suffer this fate. they will work regardless.
if u just auto mount the DVD movies, they will not be corrupted immediately, but if u use a movie player like mplayer then they will get damaged in 1 or 2 minutes. if u load the movie and immediatly seek to the middle or the end, then the player will hang and the DVD will get damaged right away.
if u check the output of dmesg u will get some of the following:
"localhost kernel: lost page write due to I/O error on hdc"
"hdc: command error: status=0x51 { DriveReady SeekComplete Error }"
"hdc: command error: error=0x50"
"ide: unknown opcode"
what is of note here is that the kernel itself is issuing the errors and that it is also giving out a "page write error msg!!!!" on a disc it just mounted, you will get to see more of this errors as u try to use the DVD further.
i have an LG DVD-RAM drive and under windows it works perfectly, the same DVD movie that works under XP simply dies under mandriva
i tried removing all burner packages (k3b, dvd+,cdrkit...), i tried turning off the HAL daemon, excluding the drive from the LVM, running things under root, underclocking my pc, turning off dma with hdparm but nothing worked
until.....
until i tried manually mounting the drive with the ISO9660 filesystem explicitly!
when i did that, the errors where gone !!, then dvd-r discs when no longer getting damaged by simply mounting them or playing them in a movie player !
dmesg would simply output that the it mounted an ISO9660 disc with joliet extensions. no more write errors!
so i figure that the distro is mounting the discs incorrectly and then the kernel is messing them up when it actually tries to read (hence write to) them.
so the way to FIX this critically flawed behavior would be to first go into mandriva's Control Center, then into the Partitions section, then into the program with the DVD icon where it says u can set up the mounting options for the drive.
leave everthing as it is but CHANGE the type from Auto to ISO9660
that's it
now, mandriva should no longer shock you crazy as u see it damaging ur DVD-R movie backups as it tries to read them !!
i hope this note would prove useful to anyone searching the net for a description of the problem+solution
i don't think the problem only affects mandriva distros since i found someone on the net in a forum claim the same thing happening to his DVD marriage backups but under Ubuntu if i'm not mistaken
peace all,
and a big hello to the guys and girls of this busy and helpful forum
rolf
Thanks a lot for the warning!
Linux is definitely not for the faint hearted.
Just less then a couple of hours ago I discovered a weird behavour in mv that made a bunch of files disappear. Not a big deal... but they could have been important files.
Anyway, enough bragging from me. Thanks a lot for the warning.
And I'm really really sorry for your movies, by the way :)
red-phoenix
thx for the moral support rolf, :)
i really like linux, but by the gods, i have still to find one distro yet without a gazzilion bug in it !! hehe