Boot fails with "No Setup Signature" after update following YumUpdateFaq

[Roy Rankin]

The Problem:

I recently upgraded a system from Fedora Core 6 to Fedora 8 using the 
YumUpdateFaq as a guide. When I tried to reboot the system with kernel 
2.6.23.9-85.fc8 the system hung in the boot process with the message "No 
Setup Signature". However I could boot the system with kernel 
2.6.22.14-72.fc6.

The investigation:

I tried reinstalling the kernel without success. I found on a mailing 
list a case where this problem was fixed by running grub-install. When I 
did this it also resolved my problem. I also remembered there has a note 
in the YumUpdateFaq about possibly needing to do this with a TODO note 
by Mads Kiilerich asking when this was required.

I contacted Mads, who acted as a sounding board as I investigated why I 
needed to run grub-install. I determined by running "less -f 
/boot/grub/stage2" on a backup taken before I ran grub-install that the 
version of the GRUB files in /boot/grub was 0.92 whereas the current 
GRUB version, since Fedora Core 5, is 0.97.

I determined that when YUM/RPM upgrades or installs GRUB, the files in 
/boot/grub do not get updated. This only happens when grub-install is 
run. When the system is upgraded from CD/DVD, Anaconda runs 
grub-install, although this can be bypassed. I had updated the system 
several times up to Fedora Core 6 using CD/DVD but skipped the GRUB 
update part of the install.

To run grub-install in Fedora 8 (or 7) it is necessary that 
/boot/grub/device.map has the new drive device naming. This file, which 
is created by Anaconda, needs to be modified from "(hd0) /dev/hda" to 
"(hd0) /dev/sda" if it was created in Fedora core 6 or earlier.

The Solution:

Mads and I came up with the following changes to the YumUpdateFaq.

1> In section 4 "Do the upgrade", the following was added

     Before booting you should usually install the bootloader from your 
new grub by running

     * grub-install BOOTDEVICE

     - where BOOTDEVICE usually is /dev/sda


2> To the end of the first paragraph under "Fedora Core 6->Fedora 7" 
discussing the IDE drive device name change, the following was added.

     In /boot/grub/device.map change /dev/hd.. to /dev/sd.. before 
running grub-install - and don't change (hd0). Changing 
/boot/grub/grub.conf may also be required.



Regards,
Roy Rankin