How do I restore the cdrom driver without a cd in the drive?

[Steve Taylor <an400@freenet.carleton.ca>]

Some of  the CD-Writing-HOWTO procedures -- or my error -- removed
the driver for my cd-writer.

It's at /dev/hdb. With this in fstab:

/dev/hdb	/cdrom		auto	defaults,noauto,ro		0	0

All was fine until I tried to  configure to  burn cd's; the  HOWTO
suggested  and I did

       test `whoami` = 'root' || echo "You must be root to execute the commands."
       cd /dev/
       umask -S u=rwx,g=rwx,o-rwx
       ./MAKEDEV loop || for i in 0 1 2 3 4 5 6 7; do mknod loop$i c 7 $i; done
       ./MAKEDEV sg   || for i in 0 1 2 3 4 5 6 7; do mknod sg$i  c 21 $i; done
       for i in ide-scsi scsi_mod sg sr_mod loop
       do
           modprobe $i || grep loop /proc/modules || echo "Module $i missing."
       done
       cdrecord -scanbus

But at next "mount /cdrom" the error is "medium not found"  unless a
cd is in the drive.

How can I restore the cdrom driver?