Recently, I upgraded my Fedora system from Fedora 9 to Fedora 10.  I used the new preupgrade utility and all seemed to go well.  Everything was great until the system rebooted and failed to find any of my logical volumes, VolGroup00 in particular.  Here is the sequence of steps I took to fix the problem:

  1. Download the Fedora 10 DVD
  2. Brun the ISO to DVD
  3. Boot from the Fedora 10 DVD and select the recovery mode option from the menu
  4. Follow the on-screen prompts

Once at a command prompt, here is what I did:

chroot /mnt/sysimage
cd /boot
mkinitrd -f -v --with=scsi_wait_scan initrd-2.6.27.7-134.fc10.i686.img 2.6.27.7-134.fc10.i686

This will recreate the ramdisk that is needed at boot time. This forces it to readd all pertinent ATA, SCSI, and hard disk controller drivers and relink all the libraries and modules.  This happened twice to me, once when going from FC 9 to FC 10, then again when going from kernel 2.6.27.5-117 to 2.27.7-134.