Booting Directly from Mirror after losing Primary

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I lost the primary drive in a mirrored system (Win2K SP3). My mirrored drive
was an identical make & model, but a different SCSI controller (different
manufacturer, even). I was able to use a fault-tolerant floppy to boot from
the mirror drive, but I had to place the SCSI controller driver on the floppy
and rename it to NTBOOTDD.SYS. I then installed a second, identical
controller (having learned my lesson!) and hard drive, and re-mirrored the
drives successfully.

My question is, how do I now get Win2K to boot from the hard disk without
needing the floppy anymore? When I try to do that, I assume it is still
trying to use the driver from the original controller which, of course,
doesn't work, but I can't figure out how to remedy the situation, nor can I
find anything on my TechNet.

TIA -
 
I lost the primary drive in a mirrored system (Win2K SP3). My mirrored drive
was an identical make & model, but a different SCSI controller (different
manufacturer, even). I was able to use a fault-tolerant floppy to boot from
the mirror drive, but I had to place the SCSI controller driver on the floppy
and rename it to NTBOOTDD.SYS. I then installed a second, identical
controller (having learned my lesson!) and hard drive, and re-mirrored the
drives successfully.

My question is, how do I now get Win2K to boot from the hard disk without
needing the floppy anymore? When I try to do that, I assume it is still
trying to use the driver from the original controller which, of course,
doesn't work, but I can't figure out how to remedy the situation, nor can I
find anything on my TechNet.

TIA -
Click to expand...
if it was a software mirror ... i had this situation and was booting
from floppy for months as I couldnt find the right way back ... fix boot
fix mbr, copying files from floppy back to hdd .. all attempts failed -
i didnt do the in place upgrade reinstall which i think would have
solved it as I had new servers due and was very glad to simply take the
server offline and rebuild it for another site!
 
It was a software mirror...AFAIK, there is no way to do a hardware mirror on
separate controllers...
 
Mark said:
It was a software mirror...AFAIK, there is no way to do a hardware mirror on
separate controllers...
Click to expand...

OK, I just wanted clarification.

Basically software mirrors (as prescribed by Microsoft) are not really
mirrors at all, in that the Intel boot code is missing on the shadow.

That's my understanding anyway.

If it was an old broken computer I didn't care about, I'd be tempted to
try marking it as Active in FDISK or hacking it with a sector editor,
but I wouldn't do this on a computer I cared about.

It's been a long time since I read up on this, but I remember at the
time deciding I'd _never_ use the Windows built-in "RAID" options.

This is not to be confused with "Dynamic" volumes, which work great on
Data partitions.
 
Hi Gerry -

Yes, well, I'm moving away from the Windows mirroring as time & resources
allow, but for now I'm stuck with it on most of my servers.

The complaint I've always had with hardware RAID, as I alluded to, is that I
can't mirror on separate controllers, so if a controller goes down, you've
had it. I also recently had a hardware RAID controller go bad and spew some
garbage onto my disks, making BOTH the primary and the mirror unreadable
simultaneously (so obviously the mirroring was still working flawlessly!).
Luckily my backup was good, but even so, it was scary.

I thought I read somewhere that Windows 2003 DOES mirror "everything" and
this isn't a problem anymore, is that not the case?

Anyway, I don't think the problem is that the disk isn't active (a la
FDISK), because the server will try to boot from the disk (as defined in the
BIOS) but I immediately get a disk read error - obviously because Windows
doesn't "understand" the disk because it was originally installed onto the
old controller & disk. Also, the partition table seems fine because it all
looked normal in Disk Management - I was able to easily break the mirror and
re-establish it onto the replacement disk.

I've thought of running Repair from Setup - then I could hit F6 to load the
driver when it starts - but is the repair procedure "smart" enough to then
install the driver onto the disk?

I guess the basic question becomes, where does Windows look to for the SCSI
driver when it starts from the hard disk? I poked around on some of my other
servers and can't figure it out. It seems you are in a Catch-22, because it
can't read the disk without the driver, yet it can't load the driver without
reading the disk. That means to me that somehow when Windows is first
installed, somehow it stores the necessary code somewhere that it can read it
first in DOS mode or something. Does that make sense?

Thanks for your help,

- Mark
 
Anyone, feel free to jump in here....

Mark C. Walton said:
Hi Gerry -

Yes, well, I'm moving away from the Windows mirroring as time & resources
allow, but for now I'm stuck with it on most of my servers.

The complaint I've always had with hardware RAID, as I alluded to, is that I
can't mirror on separate controllers, so if a controller goes down, you've
had it. I also recently had a hardware RAID controller go bad and spew some
garbage onto my disks, making BOTH the primary and the mirror unreadable
simultaneously (so obviously the mirroring was still working flawlessly!).
Luckily my backup was good, but even so, it was scary.

I thought I read somewhere that Windows 2003 DOES mirror "everything" and
this isn't a problem anymore, is that not the case?

Anyway, I don't think the problem is that the disk isn't active (a la
FDISK), because the server will try to boot from the disk (as defined in the
BIOS) but I immediately get a disk read error - obviously because Windows
doesn't "understand" the disk because it was originally installed onto the
old controller & disk. Also, the partition table seems fine because it all
looked normal in Disk Management - I was able to easily break the mirror and
re-establish it onto the replacement disk.

I've thought of running Repair from Setup - then I could hit F6 to load the
driver when it starts - but is the repair procedure "smart" enough to then
install the driver onto the disk?

I guess the basic question becomes, where does Windows look to for the SCSI
driver when it starts from the hard disk? I poked around on some of my other
servers and can't figure it out. It seems you are in a Catch-22, because it
can't read the disk without the driver, yet it can't load the driver without
reading the disk. That means to me that somehow when Windows is first
installed, somehow it stores the necessary code somewhere that it can read it
first in DOS mode or something. Does that make sense?

Thanks for your help,

- Mark
Click to expand...
 
Mark said:
Anyone, feel free to jump in here....

:
Click to expand...

Do you have a utility partition of any sort on the original drive? The
reason being is that when you create the dynamic mirror through disk
management, you only mirror the volumes that Windows uses. If you have a
utility partition at the front of the drive (like most HP, Dell, and
otther OEMs do), the offset to teh actual mirror is not correct. This
can be fixed with something like diskprobe if you're feeling up to the task.

If you didn't have the utility partition on the original drive,
something else may be going on.

Try updating your boot.ini to correct the rdisk entry to point to the
second disc.

As for installation, if by "DOS mode" you mean textmode, then yes, the
OS stores a copy of the driver loaded in textmode and it gets copied to
the correct location during GUI mode install.

Does this help?
 
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