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Windows 7: How to mirror disk? ("System" partition doesn't want to mirror)

13 Nov 2011   #1

Win 7 Pro x64
How to mirror disk? ("System" partition doesn't want to mirror)


I installed Win 7 Ultimate on my system and it has two disk drives.

When Win 7 was setup, it partitioned Disk 0 as:
  • 100MB for "System"
  • The rest for C: (incl. boot, page file, crash dump)

The machine is working fine. But now I want to mirror Disk 0 in case it ever crashes. So I plan to setup Disk 1 to mirror Disk 0.

So I change Disk 0 to a Dynamic disk and then add a mirror on Disk 1. To my surprise, it grabbed a hunk of Disk 1 and mirrored C:. But it didn't mirror the 100MB System.

Well...that's no good - if Disk 0 dies, I want to be able to boot off Disk 1, put in a new disk, resync, and be back in business with a minimum of fuss.

When I click on the System partition and say "Add Mirror", it asks me to select a disk. I select Disk 1 and it gives the error "No extents were found for the plex".

Here is what my disks look like now:

How can I have Disk 1 be a complete mirror of Disk 0 so that if Disk 0 dies, Disk 1 is ready to run?


My System SpecsSystem Spec
19 Nov 2011   #2

win 7 64 bit Pro
Two running Win 7 drives.

How about just removing your working win 7 drive and do a recovery to creat the 2nd win 7 os drive. Then reinsert the first win 7 drive back and hope that "Nanny" bootmgr doesn't interfere.

I want the same thing, two running copies of win 7 without any of this restore nonsense. Just pick the other drive while booting up. Haven't tried it yet.
My System SpecsSystem Spec
19 Nov 2011   #3

Windows 7 Ultimate SP1 64-Bit

My System SpecsSystem Spec


 How to mirror disk? ("System" partition doesn't want to mirror)

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