Booting sparkly new F12 install, error 13 from grub.

[Tom H]

> Resend as there has been no reply, with added info.
>
> I finally said to hell with it and let F12 install itself on /dev/sdb
> with all its defaults.
>
> I was surprised on the reboot when my usual grub menu from
> /dev/sda was all that showed up, no mention of an F12 install at all.
>
> Added: I had it install everything in the options list, but gave it only
> /dev/sdb to play with in the available disks menu's, & use the defaults on
> /dev/sdb, so it made a  100 meg /boot, using ext4, and a logical volume out
> of the rest of the drive.  I have NDI how to query the filesystem used there,
> other than trying to mount /dev/sdb1 as ext3 fails.
>
> So, since I had blown away a centos install to put F12 on /dev/sdb, I
> carved up a fresh grub stanza that reads like this and added it to
> /dev/sda1/grub/grub.conf:
>
> # 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 (hd0,0)
> #          kernel /vmlinuz-version ro root=/dev/sdb3
> #          initrd /initrd-version.img
> #boot=/dev/sda
> default=19
> fallback=1
> timeout=15
> splashimage=(hd0,0)/grub/splash.xpm.gz
>
> [...]
>
> #21 new stanza
> title   Fedora 12 (2.6.31.6-162.fc12.x86_64 from dev/sdb)
>        root (hd1,0)
>        kernel /vmlinuz-2.6.31.6-162.fc12.x86_64 ro root=/dev/mapper/vg_coyote-
> lv_root  LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc
> KEYTABLE=us rhgb quiet
>        initrd /initramfs-2.6.31.6-162.fc12.x86_64.img
>
> which is in fact pasted from the /dev/sdb1/grub/grub.conf except for the
> initial "root (hd1,0)" statement.
>
> So it looks as if I might have to 'chainloader +1 ' it instead, so how
> do I do that?  I've never done that before.
>
> Also, that /dev/sdb1 partition only mounts as ext4 if that is important.
>
> Added: I experimentally added a 'chainloader+1' as the next line after the
> root (hd1,0) in the /dev/sda1/grub/grub.conf, but all that seemed to do was
> add another 10 second delay before I get the error 13 message.  I would have
> thought from what little I know about grub, that this should force a reload,
> effectively a grub restart, from the mbr of /dev/sdb.  Is there something I
> need to change in the /dev/sdb1/grub/grub.conf also?

Chainloading will not work because F12 defaults to grub1, which cannot
boot from an ext4 /boot.

Your F12 stanza looks OK (I have never used so many options but why not?).

Is your /boot/grub/device.map on /dev/sda associating (hd1) to /dev/sdb?