Hi,

I was having this same problem with a Mandrake 8.1
box (Mandrake 8.1 is based on RH 7.2). On Greg's
advice I just found this on RH:

We have found an installer related bug in some hardware set-ups. After an
installation of 7.2 or upgrade of an existing system, these units report
"/dev/cdrom not a valid block device" causing the mount to fail and a
possible system crash. Running the command as root "depmod -ae" should
solve this issue. Additionally, upgrading to the latest kernel errata will
solve this issue.

http://www.redhat.com/support/resources/gotchas/7.2/

On Wed, 29 May 2002, Greg Furmanek wrote:

> There was a bug in RH.  You may want to look on their website for the
> solution.
>
> Greg
>
> > -----Original Message-----
> > From: plug-discuss-admin@lists.plug.phoenix.az.us
> > [mailto:plug-discuss-admin@lists.plug.phoenix.az.us]On Behalf Of Alpha
> > Zenon Sanchez
> > Sent: Wednesday, May 29, 2002 7:29 AM
> > To: plug-discuss@lists.plug.phoenix.az.us
> > Subject: error mounting cdrom - 'invalid block device'
> >
> >
> > Hello Linux Users:
> >
> > I purchased a Trio Hard Drive Switch that enables me
> > to choose a HD to boot from.  I have Windows NT
> > Workstation on one HD and Linux Redhat 7.2 on another.
> >  They seem to boot fine.  I can use MY CD rom, Zip 100
> > internal disk and floppy fine in Windows NT.
> >
> > However, when I boot to Linux Redhat, and try to mount
> > the CD-ROM, I get a error mounting the CD ROM
> > -'invalid block device'.  I can successfully mount my
> > floppy and zip drive though. When I use the Hardware
> > Browser in the K-Desktop, it 'sees' the CD-ROM. I try
> > to mount the CD ROM using the 'shortcut' on the
> > desktop as well as throught bash.
> >
> > My zip drive is slave to my CD ROM.  My CD Rom is set
> > to 'Master' and is connected to the secondary IDE
> > interface on the Motherboard.
> >
> > Any suggestions for this Linux newbie? :-)
> >
> > =====
> > Thanks,
> > Alpha Zenon Sanchez
> >
> > __________________________________________________
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