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Old January 6th 04, 03:27 PM
John Tindle
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Chris..
No wonder you didn't get any replies - you have a problem you don't see all
that often, but you seem to have thought it through to a logical conclusion.
You didn't mention the OS..... XP? WIN2K?
In XP there are 3 commands you can use at the recovery console command line.
BOOTCFG (/REDIRECT or /REBUILD), FIXBOOT and FIXMBR
I would use BOOTCFG with no switches to see where it's trying to boot from,
then use FIXMBR if all is as it should be.
To access the drive on the raid controller from the RC you might need the
promise driver loaded (F6 on bootup).
My first thought would be a corrupt MBR....... but let us know the real
answer....

JT.


"Chris Metzler" wrote in message
...

Hi. I posted this problem originally about three months ago, but
didn't get a response. I'm trying again, hoping someone will have
some advice for me.

My basic problem: after almost a year of working properly, the
system suddenly seems unable to boot off of either hard drive on
IDE0/1, even though the drives seem to be working perfectly when
accessed after booting through some other method.

CONFIGURATION
-------------

- A7V333-RAID w/ Athlon XP 2000, 2x Corsair 512MB CAS2 DDR333/PC2700 RAM.
- IDE0: Lite-On LTR-48125W CD-RW, WD 1200JB hard drive
- IDE1: Lite-On XJ-HD165H DVD/CD-ROM, WD 1200JB hard drive
- IDE2 (Promise): WD 800JB hard drive, WD 1200JB hard drive
- IDE3 (Promise): WD 1200JB hard drive
- Teac (?) floppy drive
- Matrox Millenium G550 video card with Viewsonic P95f+ monitor
- Creative Soundblaster Live! 5.1 sound card
- D-Link DFE-530TX+ NIC
- HP LJ1200 attached through parallel port.

The OS is located on the WD 800JB (80 GB) drive (the master on IDE2,
the first channel of the on-board Promise adapter), freeing the four
120 GB drives (one on each IDE channel) to be used as a pair of
RAID1 arrays. For faster execution, RAID functions are handled
by the OS; the on-board Promise hardware is used solely for the
extra IDE channels. The Promise *RAID* capabilities are not used
at all.

To be able to boot off CD when desired, the machine has to be
configured to boot from IDE0/1 rather than the Promise channels,
since the on-board Promise controller only allows disks to be
connected. To allow the OS to reside on a disk on the Promise
channels while still booting off IDE0/1, a bootloader is installed
into the MBR of the first 120 GB hard disk (IDE0 slave) which
points to the OS on the 80 GB drive. The BIOS is configured to
attempt to boot off off, in order:

1. the CD-RW (IDE0 master);
2. floppy;
3. the first 120 GB hard disk (IDE0 slave).

When it attempts to boot off the hard disk, it loads and executes
the bootloader which loads the OS off the 80 GB drive on IDE2.

I've had this system configured as described since early last
November, working flawlessly under heavy load for a workstation,
including numerous cold boots (after e.g. shutting down for a
thunderstorm) and some warm boots (after e.g. Linux kernel
recompiles). Not one crash or glitch of any sort, ever.


THE PROBLEM
-----------

I'm no longer able to boot from the hard drives on IDE0 or IDE1.

The POST finds the drives OK: they're listed in the opening
screen after memory is counted; and entering the BIOS setup screen
shows all four devices on IDE0/1 just fine. So it's not as if
it doesn't see the drives at all. But when it comes time to
read from the MBR, trouble. If the boot sequence is left as
above, and there are no bootable media in the CD or floppy drives,
then the system hangs after trying the floppy drive, with the
floppy drive light on; a hard reset is necessary. If the boot
order is changed so that the hard drive comes first, then the
system hangs immediately upon starting to try to boot, and again
a hard reset is necessary. No error messages of any sort -- just
a hang. Disabling CD and/or floppy booting doesn't change this;
the boot still hangs when it gets to trying to boot from the hard
drive.

However, booting off the CD or a floppy is possible. In fact, I
can boot the bootloader that would normally be in the first hard
drive's MBR off a floppy, and use *that* to access the OS on IDE2
master without any problem. It's just like things would normally
work, except the first step of the boot process goes through the
floppy rather than the IDE0 slave like it used to.

At this point, I might normally guess that there's some sort of
problem with the drive. However, the OS doesn't use BIOS routines
to access disks; it uses its own, entirely. Once the OS is booted,
I'm able to mount and mess with *all* disks, including the disk
in question. I've done hours of tests on it, filling it up and
doing compares and so forth. The disk works perfectly through the
OS; there's only a problem when attempting to access the MBR through
the BIOS at boot-time.

Another hint that it's not a problem with the disk is that I
installed the bootloader into the MBR of the *other* hard drive
on IDE0/1, the IDE1 slave, and changed the BIOS setting to boot
off that drive instead of the IDE0 slave. Exactly the same thing
happened -- system hang when it came time to boot off that disk.

The fact that there's no error messages at all made me suspicious
that maybe the MBR simply got munged somehow. So I re-installed
the bootloader into the MBR, more than once. No effect.

It is as if the BIOS can no longer read from the drives, or at least
can no longer read from their MBRs. But how can the BIOS get munged
in such a way as to work perfectly in every way *except* in trying
to boot off a hard drive?

I've spent the last three months booting off a floppy as a result
of this, and I'd really like to fix this problem if I can.

Any advice or suggestions would be welcomed.

Thanks.

-c