2006/5/29, Johnny Hughes mailing-lists@hughesjr.com:
Since morning I have an emergency. After last kernel update one of my servers didn't start. On display I see only "GRUB" :( I have 2 more servers based on CentOS too, but after the same update this servers works.
All servers have 2 HDs and works as software mirror.
I have started damaged machine using Knoppix and I can see partitions and data on both disks. Of course I have made a backup.
Anybody has the same problem? It can be hardware problem - HD diode light all the time. Or maybe something went wrong during update?
It is very strange that grub (which was already installed and working) would go bad during an upgrade.
I would boot from a CentOS-4.3 CD-1 and do this command at the isolinux prompt:
linux rescue
If it mounts the install at /mnt/sysimage ... do this:
chroot /mnt/sysimage
Then I would follow this guide to make sure that grub is installed on both hard drives and try rebooting:
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=114690
(comment #7 should make you work ... assuming you have a software mirror using sda/sdb or hda/hdb)
You may need to look at the file /boot/grub/Device.map to insure all the drives are listed properly.
Thanks for answer Johnny. It was exactly problem described above. I have reinstalled grub using rescue evironment.
Thanks.