I have the same problem doing an update from Fed13. My GRUB entry for the update is identical apart from the UUID. I do have a boot/upgrade folder with initrd and vmlinuz. The upgrade process seemed to be going OK up to that point!

Same for me. 

History may be interesting for debug: I had installed f13 and was amazed how smooth the upgrade to f14 went. Strangely, I had never been notified about an available f15 upgrade.

So I went carefully with "preupgrade" to f15 (Lovelock). After "preupgrade" finishing without apparent error, I accepted the suggested reboot and got only a blinking cursor line in the upper left corner of a 80x24 DOS window, alike bug 710756. Ctrl-Alt-Del brought me back to a grub menu with my usual choices (plus an additional f15 upgrade as first choice).

Somewhere I read upgrade f14->f16 should work. So I decided to skip f15. Same story as with f15 though. My /boot/grub/grub.conf is now:

# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE:  You have a /boot partition.  This means that
#          all kernel and initrd paths are relative to /boot/, eg.
#          root (hd0,4)
#          kernel /vmlinuz-version ro root=/dev/mapper/vg_ratonneau-lv_root
#          initrd /initrd-[generic-]version.img
#boot=/dev/sda
default=1
timeout=15
splashimage=(hd0,4)/grub/splash.xpm.gz
hiddenmenu
title Upgrade to Fedora 16 (Verne)
	kernel /upgrade/vmlinuz preupgrade repo=hd::/var/cache/yum/preupgrade ks=hd:UUID=06bfb773-9006-4c2b-b7aa-521d6a136156:/upgrade/ks.cfg
	initrd /upgrade/initrd.img
title Fedora (2.6.35.14-106.fc14.i686.PAE)
#[... removed my irrelevant standard boot choices]

(In reply to comment #2)
> title Upgrade to Fedora 16 (Verne)
>  kernel /upgrade/vmlinuz preupgrade repo=hd::/var/cache/yum/preupgrade
> ks=hd:UUID=06bfb773-9006-4c2b-b7aa-521d6a136156:/upgrade/ks.cfg
>  initrd /upgrade/initrd.img

Should the "kernel" line contain a more explicit partition identifier than what is between the colons after "repo=hd" (i.e. nothing)???


My /var/cache is on /, which is a logical volume. Unlike my other LVs, it does not show up in "blkid" under /dev/mapper, but under /dev/root. So I beleive I know what I can add to the repo= argument of the kernel.

I am trying a double-run of "preupgrade" to f16. (I also read somewhere something like it would work at the second attempt.) If that fails, I will go on as described above. But I would feel more confident, if an expert could comment on my chances to do the right thing.

(In reply to comment #3)
> (In reply to comment #2)
> > title Upgrade to Fedora 16 (Verne)
> >  kernel /upgrade/vmlinuz preupgrade repo=hd::/var/cache/yum/preupgrade
> > ks=hd:UUID=06bfb773-9006-4c2b-b7aa-521d6a136156:/upgrade/ks.cfg
> >  initrd /upgrade/initrd.img

I had no luck up to now. 

Is the following normal?
 $ file /boot/upgrade/initrd.img
 /boot/upgrade/initrd.img: xz compressed data
 $ cp /boot/upgrade/initrd.img /tmp/img.xz
 $ unxz /tmp/img.xz
 unxz: /tmp/img.xz: Compressed data is corrupt
Or does it mean that the initrd image is not generated correctly by "preupgrade"?

How can I check? What should be on this ramdisk image?

Tried grub2, as described in bug 752734#c8, with a little success.

Booting into the "Upgrade to Fedora 16" option works. Kernel is loaded, init-ramdisk is read and apparently OK. "anaconda" starts for f16 installation, but then complains that ISO images are not found: "This can happen, if complex data storage is used, like LVM." Yes, indeed...

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