Re: devfs cdrom mount pb

[Joachim Breuer <jmbreuer@gmx.net>]

"qwerty314" <qwerty314@voila.fr> writes:

> My linux box was runing fine till I decide to try devfs on RH7.3
> with 2.4.18-3 kernel after some adjustments everything is nearly OK
> with the new /dev concepts but when I try to mount a cdrom it says
> that the device is not a block device.  cat /proc/scsi/scsi gives :
>
> Attached devices:
> Host: scsi0 Channel: 00 Id: 00 Lun: 00
>   Vendor: PLEXTOR  Model: CD-R   PX-W1610A Rev: 1.02
>   Type:   CD-ROM                           ANSI SCSI revision: 02
> Host: scsi0 Channel: 00 Id: 01 Lun: 00
>   Vendor: SAMSUNG  Model: CD-ROM SC-152C   Rev: CS05
>   Type:   CD-ROM                           ANSI SCSI revision: 02
>
> and ls -l /dev/scsi/host0/bus0/target1/lun0/* gives
> crw-rw-rw-    1 root     root      21,   1 jan  1  1970
> /dev/scsi/host0/bus0/target1/lun0/generic
>
> quid?
> why has my cdrom entry switched from a block to a character device
> and how to cure it ?

You do not have the sr_mod module loaded; thus /dev/scsi/<address>/
only contains the "generic" device node, not the "cdrom" block device
node.

Either load sr_mod from a startup script (/etc/rc.modules comes to
mind), or set up the devfs module autoloader appropriately.

The device to be used for mounting is /dev/scsi/<address>/cdrom, not
/dev/scsi/<address>/generic. The generic device is "only" used for
special-purpose commands, such as for scanners or CD writing. Those
special commands are not block-level, thus "generic" is a character
device.


So long,
   Joe

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