Migrate from software mirror to Promise RAID?

The Windows 2000 Server running the Microsoft software disk mirror is still giving weird (but not disasterous) dmio and disk "bad Block" errors.  I am going to install a Promise FastTrack IDE RAID.  What should I expect to do with the disk system?  Backup and rebuild from scratch?  Will the Promise mirror in any way "inherit" the mirror structure from the OS?
admn4tndcAsked:
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j_h_oCommented:
Break the current mirror and rip one of the drives out.
Plug the remaining drive into the RAID card, setup an array, and get the server to boot on that one drive.  You will need to edit the boot.ini file as necessary to get it to find the right boot drive.  This may be tricky with the 'new' drive controller... is rebuilding the server out of the question?

As "easy" as this solution sounds, I would strongly recommend you do NOT use a Promise RAID card.  Pay the extra money for an Adaptec IDE RAID card - they're much, much more reliable.  Having used lots of Promise cards, up to the SX6000, I can honestly say I would NEVER, EVER touch a Promise card again.

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rindiCommented:
The errors you are getting can be due to deteriorating disks. This would probably mean you will also have to change the disks themselves soon. I'd look for a SATA soultion, as this is the newer technology and faster than IDE. I haven't yet had problems using Promise controllers yet, but I must confess I haven't used that many yet. I think areca raid controllers are pretty good:

http://areca.com.tw

Using a SATA raid system will of course also make it impossible to port your old array to the new one, so you'd either have to rebuild, or use an imaging software like acronis trueimage server.

http://acronis.com

Here the same applies as i_h_o has already said, edit the boot.ini file.

You could of course also get a SATA to IDE converter and connect your IDE drive that way to the SATA controller, at least temporarily until your array has been rebuilt.

Remember that when doing things like this it is allways absolutly essential you have a good, current and tested backup, or murphy is sure to make his call...
admn4tndcAuthor Commented:
I installed the Promise FastTrack on a test machine.  Good thing to practice.  One big learning:

Once the two drives are "hidden" behind the Promise controller, there is no way to run a low level surface integrity test on one of them.  I must uncable them from the Promise card and reconnect to the motherboard's IDE controllers sockets.

I'm a bit shagrined at having already ordered the Promise card when I ready the " I can honestly say I would NEVER, EVER touch a Promise card again."

Do any of the other RAID controllers provide a feature by which low level diagnostics can be passed through the RAID logic and test just one of the two (or more) hard drives?  If so I will buy an alternate card.  This swapping of cables to troubleshoot is bad.

continuing this thread a bit longer ...
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rindiCommented:
No, not as far as I know. They just check for the smart status of the HD and if there is a hot spare and the smart status say "imminent disk failure", the spare is brought into the picture and the failing disk should be replaced.
admn4tndcAuthor Commented:
Geez, I'd like to get this resolved and give you folks some goodie-points.  But the opera ain't over until ...

I just finished the low level diagnostic on both drives from the above Promise array.  Western Digital's Data Lifeguard program.  Full test -->  No error found.

So what does dmio error 30 really mean?  I'm aware there are many notes on bulletin boards across the world discussing this.  I'll ask here anyway.

Maybe it's not appropriate to change the topic of this thread?  Moderator please advise.
admn4tndcAuthor Commented:
Keep alive.  I am going to do low level Maxtor diagnostics and the Microsoft chkdsk /r on both disks this Friday 8/5.
admn4tndcAuthor Commented:
Post mortem:  I hope!

The disk surface was (slightly) bad.  For a time the Maxtor DOS diagnostic reported no trouble found while Microsoft chkdsk found bad sectors.  Then later the Maxtor "agreed" that there was some damage.  It was slight damage as the Maxtor did not give it's customary "bad sector at ...x.x.x.x" kind of result code.  In any event, it was enough to cause the dmio error in Windows 2000 Server OS.

Next came a horrible chain of events involving the software mirror, a defective boot drive letter, trashing the boot process, finding the Microsoft article about it, changing drive letters via the registry.  By then the OS had been seriously messed with.

After getting a good boot with systemvolume as C:, and re-apply the 100's of patches, finally got a good system, rebuilt mirror on new disk drive (HP sent a DOA drive the first time!).

In short, the whole purpose of buying a high-reputation vendor (HP) and implementing a high reliability disk system (Microsoft mirror) was of very little use or reward.  Very nearly the trouble of using the mirror system was a total negative rather than a saver.  Of course, the disks should not have been failing anyway.

I am now shopping for a RAID card which allows one to test the surface of each individual disk without recabling the disks back to their controllers.  The Microsoft mirror system, when you run chkdsk, tests only the disk0 surface, not the combination / redundant surfaces!
rindiCommented:
HP to me is only a high reputation vendor when you buy real servers, and not the consumer stuff which is at least as low quality as other manufacturer's products. The servers usually come with smartarray raid controllers which are among the best there are. I don't know how it goes with SATA servers and raid controllers from HP though. Also, I haven't seen many longlasting maxtor drives...
M$ and high reliability? I wonder where you got that idea? I'd allways go for hardware raid and not OS raid, in particular if that OS happenned to be one from m$...
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