On 2015-11-30 Wyatt Zacharias wrote:
--force-lvm-probe and --omit-raid-modules and it still loads dm-raid on boot.
dm-raid?? Not md-raid? What sort of RAID was on this old box? Can you still boot the old physical box itself? What does cat /proc/mdstat say? Is there a mdadm.conf? Or was this back in the raidtools days?
Adam is right, we need a fdisk -l /dev/sdX from the original box for each drive, too. If it's 0xFD then changing that might help.
So how do I get the system to completely forget about RAID, and boot off the new virtual disk? Is there a RAID config somewhere that I'm missing?
I assume you mean this box was RAID1, right? Except the partition type there's not much that stops you using a single RAID1 disk as just a normal disk. Adam's right, you don't need to try to get rid of all md/dm references in the initrd.
You could also try mdadm --zero-superblock option (see manpage). That plus getting rid of 0xFD means that single disk is for sure now just a single disk. The ancient box might not have that option for mdadm, but booting of a SRC (or similar) boot cd will let you do it. DON'T DO THIS ON THE ORIGINAL BOX unless you have some good full-disk backups.
Oh ya, send us a cat /etc/fstab. It's probably set to link root to the md/dm device or label or UUID. You'll need to change that to a single disk, UUID is easiest, use blkid to get it.
Oh ya #2, you also need to check your grub (probably grub1?) and what that says your root is, and change that just like you do for fstab. You'll need to reinstall grub on the MBR after that too. I forget how to do that in grub1! Probably just grub-install /dev/sdX.
Too bad the ancient RHEL5 doesn't have dracut (right?) and its debug shell. Quite handy (if crappy) for these situations. I've spent WAY too many hours fighting with this kind of stuff, and learned waaay more than I wanted to know, but I'm usually going the opposite way, from non-RAID -> RAID.
If you get stuck and can get me a root ssh into the box (or rescue boot) I can probably solve your problem in ten minutes! :-) I also consult, and can come onsite for a modest fee, though you already knew that! :-) ;-)