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moransa

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Windows S2K3 R2 Mirror Resynchronization time

I'm using windows explorer to mirror a pair of 200GB IDE HDs and the resynchronization is going really, really slow.  They're just installed, so there is no data, just building the mirror.  Currently it is at 45% after about 30 hours.  How long should I expect for this?  
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mdcsea

I have used the built-in Windows Server drive mirroring facility (through Disk Management) many times with a variety of systems.  On average, a 200Gb IDE pair should take 4 - 6 hours depending on the IDE speed (133, 100, or 66).  It doesn't make any difference how much data is on the disks.

You have a problem.  Anything in the Application or System logs?
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ASKER

Nada.  Before it was showing a percentage, now it just says resynching.  
There is clearly something amiss.  Make sure both physical drives are the same (or at least the same type, speed and manufacturer).  This is not absolutely essential, but if they're not, there could be problems.

If there's nothing in the System or Application logs, it's really hard to know what's going on.  Since there is no data on the array, have you tried a restart?  A restart before the sync completes will crash the array but it's starting to sound like it would like it will never complete anyway.

If I had to make a best guess - I'd say a bad hard drive but that's premature.  Shut down, physically disconnect one of the drives and restart the machine.  See if you can see the one drive, properly formatted and accessible with as many volumes as you may have originally created.  Break the mirror if (Windows still thinks it exists) so you have a single, Dynamic volume.  Make sure you can access the drive, copy a file onto each volume (if more than one) and then confirm it copied correctly.  Check the System log to see if there are any errors immediately after the restart.  

Shut down, reconnect the other drive and restart.  Again, go to Disk Manager and see if you can successfully create volume(s) on the new disk (not a mirror).  You should have two drives with one or more volumes.  Again, check for errors in the System log.  Again, copy files onto this newly added drive.

Restart again.  Enter Disk manager.  Delete all volumes on one of the drives.  Make sure both drives are Dynamic.  Try recreating the mirror between the volumes.  If you have multiple volumes, start with a small one.  If you have only one volume make sure it does not use all the space of the disk - always leave a bit of free space (my practice).  See what happens when you try to resync.

Good Luck!

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ASKER

The drives are exactly the same manufacturer and model, right down to the bits and bytes.  I broke the mirror, deleted the volumes, and started over.  This time I left 80MB out of the volume.  The build took some time over the weekend while the server wasn't being hit, but it completed.  So I tried to copy some data over and it went into resynching again, which I expected, but it took hours, and then the server crashed.  I ran it again, let it run overnight and it still displayed no percentage.  So I broke the mirror again this morning, created a new volume (with the 80MB hanging off) and I'm copying the data to this one drive, then I will build the mirror and see how long the resynching process takes.  

Comments?  Ideas?  
It's starting to seem like a case of, 'if it's not the hard drives, it must be the controller'.  Some things I should confirm:

1.  You've tried a different IDE cable.
2.  You tried the drives on the other channel of the existing controller.

Can you put the drives on a different controller - not just the other channel of the controller you're using but a different controller entirely?  PCI IDE controllers are pretty cheap and you might have one lying around.  
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ASKER

It's plugged into the MoBo IDE, I will try another cable.... again....  and try a PCI controller after that.  
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mdcsea

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Thanks much.  I'm putting in another controller.