Very Computer

    I am having a problem with a CD-Rom burner of mine.  I'm running
RedHat Linux 6.1 and it finds it, but when I test it with a CD (The 6.1
Install CD), it gives me this message:

    mount:  block device /dev/scd0 is write-protected, mounting
read-only
    mount:  wrong fs type, bad option, bad superblock on /dev/scd0,
                   or toomany mounted filesystems

Carl

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Quote:>    I am having a problem with a CD-Rom burner of mine.  I'm running
>RedHat Linux 6.1 and it finds it, but when I test it with a CD (The 6.1
>Install CD), it gives me this message:
>    mount:  block device /dev/scd0 is write-protected, mounting
>read-only

When you mount a CD-ROM, is is always mounted as read-only.  Always.
Writing to a blank CD-R(W) is done without mounting a filesystem, done
through the /dev/sgX devices, and done using the cdrecord or cdrdao
programs.  Read http://www.linuxdoc.org/HOWTO/CD-Writing-HOWTO.html and
the man pages for cdrecord and mkisofs for more info on the whole subject.
HTH,

--
Matt G / Dances With Crows        \          In the MS-DOStrix,
There is no Darkness in Eternity   \----\    there is no fork().
But only Light too dim for us to see     \    
    ===== Usenet: ceci n'est pas une guerre des flammes =====

Anyway, what happens when you try this?:
# mount -t iso9660 /dev/scd0 -o ro /mnt/cdrom

That should give a more illuminating error message and rule out
permission problems or /etc/fstab as a source of problems.  The line in
your /etc/fstab should be like so:
/dev/scd0   /mnt/cdrom   iso9660   noauto,user,ro   0   0

Or try /dev/sr0 instead of /dev/scd0 ?  They're supposed to point to the
same place, but sometimes one works and the other doesn't.

Also, you should have a look at /var/log/dmesg and make sure that your
CD-RW is getting recognized as an IDE-SCSI device.  If you have IDE CD-ROM
support compiled, you may have to pass the "hdX=ide-scsi" option to the
kernel at boot time so the IDE driver doesn't grab the CD and refuse to
let go.

Quote:>And this is on a CD that already has data on it.  I wasn't trying to burn to

--
Matt G / Dances With Crows        \          In the MS-DOStrix,
There is no Darkness in Eternity   \----\    there is no fork().
But only Light too dim for us to see     \    
    ===== Usenet: ceci n'est pas une guerre des flammes =====

mount:  wrong fs type, bad option, bad superblock on /dev/scd0,
                   or toomany mounted filesystems

And this is on a CD that already has data on it.  I wasn't trying to burn to
one that HAS data on it, I was trying to test if the Burner was working
correctly or not by mounting a RH installation CD.

Thanks,
Carl

Quote:> Anyway, what happens when you try this?:
> # mount -t iso9660 /dev/scd0 -o ro /mnt/cdrom

> That should give a more illuminating error message and rule out
> permission problems or /etc/fstab as a source of problems.  The line in
> your /etc/fstab should be like so:
> /dev/scd0   /mnt/cdrom   iso9660   noauto,user,ro   0   0

> Or try /dev/sr0 instead of /dev/scd0 ?  They're supposed to point to the
> same place, but sometimes one works and the other doesn't.

Quote:> Also, you should have a look at /var/log/dmesg and make sure that your
> CD-RW is getting recognized as an IDE-SCSI device.  If you have IDE CD-ROM
> support compiled, you may have to pass the "hdX=ide-scsi" option to the
> kernel at boot time so the IDE driver doesn't grab the CD and refuse to
> let go.

scsi : 0 hosts.
scsi : detected total.
scsi0 : AdvanSys SCSI 3.2F: PCI Ultra 240 CDB: IO EC00/F, IRQ 11
scsi : 1 host.
   Vendor: MATSHITA  Model: CD-R   CW-7502    Rev: 3.02
   Type:   CD-ROM                             ANSI SCSI revision: 02
Detected scsi CD-ROM sr0 at scsi0, channel 0, id 0, lun 0
sr0: scsi3-mmc drive: 8x/8x writer xa/form2 cdda tray

Now the second part of that is where I start to get a little lost.
Haven't had a whole lot of expirience(sp) with kernel's yet.  I do have
an IDE CD-ROM on my system  (Creative 32X), could that affect it?  

Thanks,
Carl

Quote:>Tried mounting with the readonly command.  Still gives error message
>`wrong fs type, bad superblock' etc..

Quote:>I checked dmesg, this is everything it referenced to SCSI:
>scsi : 0 hosts.
>scsi : detected total.
>scsi0 : AdvanSys SCSI 3.2F: PCI Ultra 240 CDB: IO EC00/F, IRQ 11

Quote:>scsi : 1 host.
>   Vendor: MATSHITA  Model: CD-R   CW-7502    Rev: 3.02
>   Type:   CD-ROM                         ANSI SCSI revision: 02
>Detected scsi CD-ROM sr0 at scsi0, channel 0, id 0, lun 0
>Now the second part of that is where I start to get a little lost.
>Haven't had a whole lot of expirience(sp) with kernel's yet.  I do have
>an IDE CD-ROM on my system  (Creative 32X), could that affect it?  

--
Matt G / Dances With Crows        \          In the MS-DOStrix,
There is no Darkness in Eternity   \----\    there is no fork().
But only Light too dim for us to see     \    
    ===== Usenet: ceci n'est pas une guerre des flammes =====

Quote:> So you have a CD-ROM and a CD-RW?  This could be a problem; it seems as
> though the ide-scsi emulation of SCSI CD-ROMs doesn't play nicely with the
> IDE CD-ROM driver.  Next time you boot the machine, at the lilo: prompt,
> enter the following:
>   linux hdX=ide-scsi hdY=ide-scsi
> where X is the location of your CD-RW and Y is the location of your
> CD-ROM.  That should prevent the IDE CD-ROM driver from grabbing any of
> the CDs.  One of your CD-ROM drives will be /dev/scd0 and the other will
> be /dev/scd1.

scsi0: MEDIUM ERROR on channel 0, id 0, lun 0, CDB: Read (10) 00 00 00
00 10 00 00 01 00
Info fld=0x10, Current sr0b:00: sense key Medium Error
Additional sense indicates L-ec uncorrectable error
CD-ROM I/O error: dev 0b:00, sector 64
isofs_read_super: bread failed, dev=0b:00, iso_blknum=16, block=32

Thanks again,
Carl

Check cable lengths, and termination before going on any further.

Each end of the bus should be terminated with an active terminator or by
a device with built-in active termination.  Your SCSI card counts as
such a device.  No other device on the bus should have termination.

There should be no dangling ends of the cable.  Make sure the last
connector at the end of the cable is connected to a device or a
terminator.

If your bus is Ultra-Wide SCSI, make sure the total amount of cabling is
1.5m or less.  If it's Ultra-SCSI, the limit is 3m.  If it's fast- or
fast-wide SCSI, then the limit is 6m.  If it's LVD (Ultra2 or Ultra3),
then the limit is 12m.  If your cables are too long, you will get
failures.

Note that if you have any non-LVD devices on your bus, then the bus will
not be using LVD, and will instead be running as Ultra- or Ultra-Wide.

-- David

Quote:>Ah!  This helps enomously.
>Check cable lengths, and termination before going on any further.

        -Kenny

--
Kenneth R. Crudup   Sr. SW Engineer, Scott County Consulting, Washington, D.C.
Home1: PO Box 914               Silver Spring, MD 20910-0914
Home2: 38010 Village Cmn. #217  Fremont, CA 94536-7525          (510) 745-8181
Work:  19420 Homestead Road     Cupertino, CA 95014-0606        (408) 447-6654

-Carl