Question about dynamic volumes on a 2000 server

  • Thread starter Thread starter Mike Matheny
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Mike Matheny

I have a client that had a single 20g SCSI drive in a Dell PowerEdge server.
Dell places a 55mb diagnostic partition at the beginning of the drive. He
purchased 2 35g SCSI drives for me to install and set up as a mirror set. I
first began by installing one of the new SCSI drives, and using Ghost to do
a drive to drive copy. This copied the 55g diag partition, as well as the
system and a data partition. I removed the orig. drive and booted up with
the new drive, and all works fine. Converted the new drive to a dynamic
volume, and for some reason, it moved the diag. partition to the center,
between the two NTSC partitions. Well, rebooted to check out the diag. part,
and it still allowed me to boot to the diag. part. OK, so I add the second
drive, and converted it into dynamic volume to create a mirror, and then I
realize that Windows mirroring only mirrors partitions, not full drives like
a RAID controller would do, and I could not select the diag. part to be
mirrored. Ok, so I broke the mirrors, changed back to a simple volume,
cleared off all partitions on the 2nd drive, boot to a DOS diskette and used
Ghost to copy the complete 1st drive to the second. Ok, now I have identical
drives, and both boot up independently. So I boot back into Windows, change
the 1st drive back into a dynamic volume, and all is well. I change the 2nd
drive into a dynamic volume, and the diag. part disappears! This does not
happen with the 1st drive. What is going on here? How can I make a perfect
mirror that will allow full functionality, including booting into the diag.
part. if I need to?
 
I have a client that had a single 20g SCSI drive in a Dell PowerEdge
server. Dell places a 55mb diagnostic partition at the beginning of
the drive. He purchased 2 35g SCSI drives for me to install and set up
as a mirror set. I first began by installing one of the new SCSI
drives, and using Ghost to do a drive to drive copy. This copied the
55g diag partition, as well as the system and a data partition. I
removed the orig. drive and booted up with the new drive, and all
works fine. Converted the new drive to a dynamic volume, and for some
reason, it moved the diag. partition to the center, between the two
NTSC partitions. Well, rebooted to check out the diag. part, and it
still allowed me to boot to the diag. part. OK, so I add the second
drive, and converted it into dynamic volume to create a mirror, and
then I realize that Windows mirroring only mirrors partitions, not
full drives like a RAID controller would do, and I could not select
the diag. part to be mirrored. Ok, so I broke the mirrors, changed
back to a simple volume, cleared off all partitions on the 2nd drive,
boot to a DOS diskette and used Ghost to copy the complete 1st drive
to the second. Ok, now I have identical drives, and both boot up
independently. So I boot back into Windows, change the 1st drive back
into a dynamic volume, and all is well. I change the 2nd drive into a
dynamic volume, and the diag. part disappears! This does not happen
with the 1st drive. What is going on here? How can I make a perfect
mirror that will allow full functionality, including booting into the
diag. part. if I need to?
Click to expand...

What you are seeing is expected behavior. There really is not a way to
mirror a EISA partition using software mirroring. The EISA partition is
still there on the mirror but isn't being reported because the disk is
Dynamic. When you convert a disk to Dynamic you are changing all
partitions to a type 42. Then all other partition info is read from the
LDM database at the end of the drive.


Leonard Severt

Windows 2000 Server Setup Team
 
Mike,

Mirrors are built on a filesystem level. If Windows can't read the
filesystem Windows can't mirror it.

Windows is designed not to mount/read the filesystem of the vendor
diagnostic partitions. There's no way to coax Windows into mirroring this
partition.

-Matt
 
I realize this, but why does the diag part stay on the first drive after I
convert it to dynamic from basic, but on the 2nd drive, when I convert from
basic to dynamic, it disappears? Why won't it just stay there, and let me
mirror the 2 NTFS paritions from the 1st drive? Does it have something to do
with the 2nd drive not being a boot drive?
 
Well, looked at the drive management screen today, and the diag part has
suddenly appeared on the mirrored partition! Strange thing is, it shows 55mb
partiton and 55mb free on both mirrored drives and no filesystem installed,
while on the original partition, it showed 55mb partition and 28mb free and
FAT file system installed! What's even weirder is, it still boots to the
diagnostics on the 1st mirrored drive, which indicates it works fine, just
looks wierd!
 
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