I must have really shot myself in the foot on this one.
I reinstalled CentOS 4.4 (have to, for now) on my test machine, exactly the way it was before (same options anyway), but when it comes up, I get:
Booting 'CentOS-4 x86_64 (2.6.9-42.ELsmp)'
root(hd1,0) Filesystem type is ext2fs, partition type 0x83 kernel /vmlinuz-2.6.9-42.ELsmp ro root=LABEL=/ rhgb quiet
Error 15: File not found
Press any key to continue...
If I press any key, I get a garbled screen that is nearly impossible to read. So, I rebooted from the DVD in rescue mode, ran fdisk to verify that the partitions are set up correctly, ran e2fsck on all three formatted partitions (sde1 - /boot, sde3 - /, sde6 - /home), ran e2label to make sure the labels are set correctly and everything checks out. All the file images are present in /boot where they should be, and the device map shows hd1 is /dev/sde3.
Is my disk rotten or something? Everything is in the right place (so far) but it won't boot.
The test machine is of a type I don't recognize, it's running a 2.88GHz Xeon processor with 8Gb of memory, a 4-disk RAID SATA controller (currently configured as 4 separate drives, one of which is "spared" because it did go bad) and a WD hard drive as /dev/sde. It has a 17" FP monitor with an ATI <something> XL video card, though I doubt that last part is terribly relevant.
Suggestions welcome.
On May 23, 2007, at 2:08 PM, Mark Hull-Richter wrote:
the device map shows hd1 is /dev/sde3.
Hmm, this is the most suspicious part of your message. First of all, hd1 can't be /dev/sde3 - it would have to be /dev/sde. Thus (hd1,0) is /dev/sde1. Second, the device map is used by the grub installer, but not by grub itself. It uses the actual BIOS boot order - hd0 is the first hard disk, hd1 is the *SECOND* hard disk. So if you boot grub with this configuration, it will try to load an operating system from a different hard drive!
On 5/23/07, Scott Lamb slamb@slamb.org wrote:
On May 23, 2007, at 2:08 PM, Mark Hull-Richter wrote:
the device map shows hd1 is /dev/sde3.
Hmm, this is the most suspicious part of your message. First of all, hd1 can't be /dev/sde3 - it would have to be /dev/sde. Thus (hd1,0) is /dev/sde1. Second, the device map is used by the grub installer, but not by grub itself. It uses the actual BIOS boot order - hd0 is the first hard disk, hd1 is the *SECOND* hard disk. So if you boot grub with this configuration, it will try to load an operating system from a different hard drive!
Typo - my bad. The device map contains this:
(fd0) /dev/fd0 (hd0) /dev/sdd (hd1) /dev/sde
What happened to sda-sdc (i.e., why aren't they in the device map at all)?
Anyway, I replaced the hd1's in the grub.conf with hd4s. It seems strange that the grub loader would not have a map that actually maps to the hardware, but now the system gets up to the "Booting 'CentOS 4..." prompt and reboots instantly. Apparently grub doesn't ONLY use the strict hardware order, unless, for some reason, the hardware doesn't see sda-sdc either (???).
When I boot the DVD in rescue mode, it asks if my root file system is on sda1 or sde3 - does that help (sda1 has data on it, no os)?
-
Mark Hull-Richter -
Scott Lamb