Disk Mirroring: Cpq Diagnostic Partition?

[Ben Nagel]

Hi,

I use W2K to software mirror the OS (Boot) partition on an ML370 G2. Everything mirrors except the Compaq diagnostic partition.

First Question: What's the function of this partition, and by losing it do I lose any sort of real diagnostic capability?

Second Question: If I lose the disk that holds that partition, will there be any problems booting from the shadow copy and swapping in another drive?

Thanks,
Ben

[Ron Amos]

Hi Ben,

Server Diagnostics can be run via a floppy Disk created with SP19737.EXE available at: http://www.compaq.com/support/files/server/us/download/15446.html

First Question: This Partition on a G2 Server such as yours is only used for Server Diagnostics which can be run as described above.

Second Question: No there will be no problem booting to shadow copy as long as you point to Partition 1. When you swap in another Drive and restore mirror, again point to partition 1 not partition 2 as it was originally. There will be no loss functionality.

If you must have the Compaq Diagnostic Partition it must be installed prior to restoring mirror.

RON

[Ben Nagel]

Thanks, Ron.

Thanks for the good information. We ran a test based on your note above, and I have one follow-up question.

The test:
The disk with our original boot partition was Disk 0 (of course), so we mirrored that against Disk 1. Disk 0 had the Compaq diagnostic partition. We removed Disk 0, and we booted using a floppy disk with its boot.ini pointing to partition 1. We were able to boot, so it looked like the mirroring was working just fine.

Now we wanted to reconstruct the mirror. First we tried replacing Disk 0 with a new (unformatted) disk, but then we couldn't boot (even with our floppy disk), because the system was looking to partition 1 on the new (unformatted) disk. So, we moved Disk 1 into the Disk 0 slot and put the new disk in the Disk 1 slot. We were able to boot and restore the mirror. Everything functioned fine on the server. We altered the boot.ini on drive C: to point to partition 1 (because now neither disk in our mirror set has a Compaq diagnotic partition).

Our only problem now is this: when we try to boot from the C: drive, the boot process hangs just before W2K starts to load. The screen reads:
Attempting Boot From CD-ROM
Attempting Boot From Floppy Drive (A:)
Attempting Boot From Hard Drive (C:)

Then it just hangs with a blinking cursor and there is no disk activity.

We can, however, still boot fine from the floppy disk (with a boot.ini identical to the one on C:).

The question:
Could it be that the system expects to find the Compaq partition when booting from the hard drive? What can we do to get ourselves booting from C: again?

Thanks.

[Ron Amos]

Hi Ben,

As long as Hard Drive ID #0 or "C" Drive is "Active", Has a good MBR (Master Boot Record), appropiate loader files, and Boot.ini points to Partition 1 it will boot.

No the system does not care whether there is a System Partition (EISA Partition) in place. I would bet you need to set "C" Drive "Active".

Give this a try -- I am taking holiday's Thursday & Friday. Will not be back until 11:00pm Monday Oct 28.

Good Luck,

Ron

[Ben Nagel]

Thanks, Ron.

I have used Fdisk to verify that the first disk's (Disk 0) first partition (Partition 1) is active.

Disk 0 is part of a mirror set with Disk 1, and its first partition is C:. It has the same exact files at the root of C: that my floppy does (ntdetect.com, ntldr, and boot.ini), and the boot.ini is structured the same way on C: as it is on the floppy.

Unfortunately, the ML370 still hangs at the screen reading "Attempting Boot From Hard Drive (C:)."

I would think that if there was a problem with the way boot.ini was set up or if the correct boot files weren't there, we would see an error telling us what the problem was. Instead, we get no error, and the boot process just hangs. What are the last few things that the Compaq POST routine looks for before handing off to the OS?

Thanks again for your help.

Ben

[Ron Amos]

Hi Again Ben,

You didn't mention how big your "C" Partition is? There could be a problem if loader files are outside the 4GB Barrier. Microsoft Support would be the best source for help here.

Only other possibility could be a corrupt MBR (Master Boot record) as booting from a floppy it accesses the MBR on the floppy. Should MBR on Hard Drive be defective then access Microsoft knowledge base to fix or contact them directly.

Otherwise your boot.ini should point as follows:

To Boot Disk ID #0
Default=multi(0)disk(0)rdisk(0)partition(1)

To Boot Disk ID #1
Default=multi(0)disk(0)rdisk(1)partition(1)

There would be nothing else unique about a ML370 G2 other then setting your Controller Order in ROM Based BIOS (RBSU) and having Partition (1) Active, you have indicated that you verified this fact.

Good Luck,

Ron