I used yum to update my fc6 install to fc7 but I can only boot using 2.6.20-1.2962.fc6 as 2.6.22.1-33.fc7 will not work.

I have a raid 1. fc6 boots and finds the "Linux raid autodetect" partitions hda1 and hdb1 automatically and boots perfectly using md0.

[root@srv1 ~]# mdadm --detail --scan
ARRAY /dev/md0 level=raid1 num-devices=2 UUID=7d6756f9:7d774e9b:cacca85b:822777f8

fc7 bombs out. It complains about /dev/md0 not being defined in the config file (although I built and stuck an mdadm.conf file into /etc with no luck) and then tries to fall back to /dev/hda2 but that doesn't exist because fc7 seems to see hda and hdb as sda and sdb (huh?).

I've booted into the fc7 emergency disk and it finds /dev/md0 with no trouble and I can chroot /mnt/sysimage just fine. I've tried backing up the initrd and making a new one forcing every probe possible and throwing in --with=lvm and --with=raid just for completeness.

Percussion therapy did not work either. Nor did swearing at the machine profusely.


What else can I try? Please anyone - any ideas?

Inspect grub.conf/fstab and change any F7-related hd(x) references to sd(x). Also change the commented references.

If you made changes in fstab, then try remaking (mkinitrd) the F7 initrd image, preferably from the F7 rescue mode.

Thanks! Success. Here is what I did:

(1) booted with emergency fc7, chroot /mnt/sysimage
(2) changed all (hd0,0) to (sd0,0) - there were no hd(0) or sd(0). Changed #boot=/dev/hda to #boot=/dev/sda
(3) remade the initrd again
(4) on reboot grub complained about there not being an (sd0,0)
(5) using the "a" option in the grub boot screen, I changed (sd0,0) back to (hd0,0) (makes sense...)
(6) hit "b" and off it went.
(7) re-edited the /etc/grub.conf file back to previous config except keeping /dev/sda instead of /dev/hda


Thanks.


I am thinking of updating a remote machine to fc7 that I can't psychically get to for operations at this level (booting emergency disks). Did my problems come only because I was booting from a raid; do I need to change grub.conf to sda on that system (like would it be a formula thing to do); or would it be too risky full stop - better to stay with fc6?

Didn’t mean for you to change the grub root (hdx,y) entries, but you figured that out.

I have done several FC6 to F7 yum upgrades on systems using PATA drives (hda becomes sda) without the problem you described and all had either mdadm raid1 or raid1/raid5 combos, so I don’t think that’s the issue.

Doing a remote upgrade always carries a higher degree of failure-recovery risk, so it’s always a good idea to ask what it will cost for someone on the other end to fix a problem before starting the remote upgrade.