Last night I used the included cdroms from the book “Red Hat Linux 7.2 Bible” to upgrade my RH 7.0 
machine.   Now I can not mount the cdrom   (not a valid block device).  I looked at the dmesg (?) 
file and it has a lines that say  it recognizes the cdrom  and it also recognizes the floppy, fd0.  
 Farther down in this file I get several lines that say these are invalid block devices.   I don’t 
think I can mount the floppy either.

One of the passages from the book says under:
  Reconfiguring the kernel
      Deciding to reconfigure the kernel
          Block devices:

“For some older disk drives, you may need to use an old disk-only driver on the primary interface.  
With that selected, you won’t be able to have an IDE/ATAPI CD-ROM attached to the primary IDE 
interface.  However, turning on the disk-only driver may be necessary for some older disk drives.”

The cd drives I am using are rather old  x4 and x8 but they are not on the primary IDE.  I also 
allowed this upgrade to change my boot loader to GRUB from LiLo.   

Any ideas what I should do try next.  Is the reconfigure of the kernel mensioned in the book just 
changing boot options or is it a recompile?  

thank for any help
rod holcomb