CDROM device suddenly doesn't exist....

[Charlie]

Hello,

Debian testing 4.6.0-1-amd64 #1 SMP Debian 4.6.4-1 (2016-07-18) x86_64
GNU/Linux

Suddenly have a CDROM problem:
$ mount /media/cdrom
mount: /dev/sr0 is write-protected, mounting read-only
mount: special device /dev/sr0 does not exist

Did:

# ls -l /dev/sr0
ls: cannot access '/dev/sr0': No such file or directory

# cd /dev
/dev# mknod sr0 b 11 0
/dev# chgrp cdrom sr0
/dev# chmod 660 sr0

Before reboot get:

~$ mount /media/cdrom
mount: /dev/sr0 is write-protected, mounting read-only
mount: /dev/sr0 is not a valid block device

After rebooting makes Midnight Commander [mc] unresponsive?

Obviously have done something wrong.

Any help to get this CDROM working again, appreciated.

Charlie
--
Registered Linux User:- 329524
***********************************************

Calamities are of two kinds: misfortunes to ourselves, and good
fortune to others. --Ambrose Bierce, The Devil's Dictionary

***********************************************

Debian GNU/Linux - Magic indeed.

-----------------------------------------------------

[Charlie]

Post by Charlie
Hello,
Debian testing 4.6.0-1-amd64 #1 SMP Debian 4.6.4-1 (2016-07-18) x86_64
GNU/Linux
$ mount /media/cdrom
mount: /dev/sr0 is write-protected, mounting read-only
mount: special device /dev/sr0 does not exist
# ls -l /dev/sr0
ls: cannot access '/dev/sr0': No such file or directory
# cd /dev
/dev# mknod sr0 b 11 0
/dev# chgrp cdrom sr0
/dev# chmod 660 sr0
~$ mount /media/cdrom
mount: /dev/sr0 is write-protected, mounting read-only
mount: /dev/sr0 is not a valid block device
After rebooting makes Midnight Commander [mc] unresponsive?
Obviously have done something wrong.
Any help to get this CDROM working again, appreciated.
Charlie

After contemplation, an addendum:

Now I get:

$ mount /media/cdrom0
mount: /dev/sr0 is write-protected, mounting read-only
mount: special device /dev/sr0 does not exist

again.........

Will have to see what else I can find.

Charlie
--
Registered Linux User:- 329524
***********************************************

It is dangerous to be right when the government is
wrong. .......Voltaire

***********************************************

Debian GNU/Linux - Magic indeed.

-----------------------------------------------------

[Thomas Schmitt]

Hi,

Post by Charlie
mount: /dev/sr0 is write-protected, mounting read-only
mount: special device /dev/sr0 does not exist

Does command dmesg report something about "sr0" after this happened ?


Have a nice day :)

Thomas

[Ric Moore]

Post by Thomas Schmitt
Hi,

Post by Charlie
mount: /dev/sr0 is write-protected, mounting read-only
mount: special device /dev/sr0 does not exist

Does command dmesg report something about "sr0" after this happened ?
Have a nice day :)

Do you have a bios selection for the cdrom drive?? Last time this
happened to me, replacement of the drive fixed the problem. Ric

[Charlie]

Post by Ric Moore
Do you have a bios selection for the cdrom drive?? Last time this
happened to me, replacement of the drive fixed the problem. Ric

After contemplation, my reply is:

Thanks Thomas and Ric,

Nothing in dmesg report and I will look at the BIOS and see what is to
be seen there.

Not using that drive hardly at all. I'm not too worried, but it just
seemed a strange thing to happen.

Thank you both for your help.

Charlie
--
Registered Linux User:- 329524
***********************************************

A man is either free or he is not. There cannot be any
apprenticeship for freedom. --Amiri Baraka

***********************************************

Debian GNU/Linux - Magic indeed.

-----------------------------------------------------

[Charlie]

Post by Ric Moore

Post by Thomas Schmitt
Hi,

Post by Charlie
mount: /dev/sr0 is write-protected, mounting read-only
mount: special device /dev/sr0 does not exist

Does command dmesg report something about "sr0" after this
happened ?
Have a nice day :)

Do you have a bios selection for the cdrom drive?? Last time this
happened to me, replacement of the drive fixed the problem. Ric

After contemplation, my reply is:

Just for completeness:

Checked the BIOS to see if there was anything that might be changed or
to be discovered, without result.

Changed some of the numbers in:
/etc/udev/rules.d/persistent-cd.rules

Which brought up error messages about /dev/sr0 not being a block device.

Then went through the: mknod sr0 b 11 0 process as explained previously
again.

Rebooted the system.

Ran through discovering what was now happening- surprise:

ls -l /dev/sr0
brw-rw----+ 1 root cdrom 11, 0 Jan 12 08:54 /dev/sr0

Did eject, put in a data DVD, and read it.

Ejected it again closed the drawer

Retried eject:

~$ eject
eject: tried to use `/dev/sr0' as device name but it is no block device
eject: unable to find or open device for: `cdrom'

So the drive is definitely crook.

Thanks for your suggestions. Much appreciated.

Charlie
--
Registered Linux User:- 329524
***********************************************

He is a hard man who is only just, and a sad one who is only
wise. --Voltaire

***********************************************

Debian GNU/Linux - Magic indeed.

-----------------------------------------------------