[CentOS] Problems reading a backup data DVD

Mon Aug 20 01:30:30 UTC 2007
Robert <kerplop at sbcglobal.net>

Mark Hull-Richter wrote:
> I wrote a bunch of files to a backup DVD about two months ago and now 
> neither of my drives will read it.  I get mount errors from "not a 
> directory" to something like "unrecognized file system type" and so 
> on, usually after a really long wait and a notice about how the drive 
> is write-protected (duh).
>
> Here's what happened most recently:
>
> # mount /dev/hdc /mnt
> mount: block device /dev/hdc is write-protected, mounting read-only
> mount: wrong fs type, bad option, bad superblock on /dev/hdc,
>        missing codepage or other error
>        In some cases useful info is found in syslog - try
>        dmesg | tail  or so
> # dmesg | tail -40
> hdc: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
> hdc: cdrom_decode_status: error=0x40 { LastFailedSense=0x04 }
> ide: failed opcode was: unknown
> hdc: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
> hdc: cdrom_decode_status: error=0x40 { LastFailedSense=0x04 }
> ide: failed opcode was: unknown
> hdc: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
> hdc: cdrom_decode_status: error=0x40 { LastFailedSense=0x04 }
> ide: failed opcode was: unknown
> hdc: ide_intr: huh? expected NULL handler on exit
> hdc: ATAPI reset complete
> end_request: I/O error, dev hdc, sector 5118720
> Buffer I/O error on device hdc, logical block 639840
> hdc: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
> hdc: cdrom_decode_status: error=0x40 { LastFailedSense=0x04 }
> ide: failed opcode was: unknown
> hdc: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
> hdc: cdrom_decode_status: error=0x40 { LastFailedSense=0x04 }
> ide: failed opcode was: unknown
> hdc: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
> hdc: cdrom_decode_status: error=0x40 { LastFailedSense=0x04 }
> ide: failed opcode was: unknown
> hdc: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
> hdc: cdrom_decode_status: error=0x40 { LastFailedSense=0x04 }
> ide: failed opcode was: unknown
> hdc: ide_intr: huh? expected NULL handler on exit
> hdc: ATAPI reset complete
> hdc: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
> hdc: cdrom_decode_status: error=0x40 { LastFailedSense=0x04 }
> ide: failed opcode was: unknown
> hdc: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
> hdc: cdrom_decode_status: error=0x40 { LastFailedSense=0x04 }
> ide: failed opcode was: unknown
> hdc: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
> hdc: cdrom_decode_status: error=0x40 { LastFailedSense=0x04 }
> ide: failed opcode was: unknown
> hdc: ide_intr: huh? expected NULL handler on exit
> hdc: ATAPI reset complete
> end_request: I/O error, dev hdc, sector 64
> isofs_fill_super: bread failed, dev=hdc, iso_blknum=16, block=16
>
> Is there any way to read what's on this DVD (so I can back -up the 
> files again, hopefully with better results)?
>
> Secondary related question:  I noticed that my CentOS boot DVD does 
> not automount when I put it in either drive - why is that?
>
> Thanks.
>
> mhr
>
I would suspect IDE cable, DVD drive,  P/S, motherboard (assuming an 
on-board IDE channel) in that order. Don't overlook the drive's power 
connector, either.

Do you have another machine you can try that boot DVD in? Can you read a 
CD in the failing drive? Have you been monkeying around with the kernel? 
Is the "DVD drive" really a DVD drive or is it only for CDs?