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>> Instead, how about a 6-drive RAID 10 array with no hot spare? My |
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>> guess is this would mean much greater fault-tolerance both overall and |
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>> during the rebuild process (once a new drive is swapped in). That |
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>> would mean not only potentially increased uptime but decreased |
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>> monitoring responsibility. |
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> |
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> RAID10 with six drives can be implemented one of two ways, |
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> |
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> Type 1: A B A B A B |
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> |
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> Type 2: A B C A B C |
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> |
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> If your controller can do Type 1, then going with six drives gives you |
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> better fault tolerance than four with a hot spare. |
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> |
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> I've only ever seen Type 2, so I would bet that's what your controller |
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> will do. It's easy to check: set up RAID10 with four drives, then with |
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> six. Did the drive get bigger? If so, it's Type 2. |
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> |
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> If it's Type 2, then four drives with a spare is equally tolerant. |
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> Slightly better, even, if you take into account the reduced probability |
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> of 2/5 of the drives failing compared to 2/6. |
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Thank you very much for this info. I had no idea. Is there another |
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label for these RAID types besides "Type 1" and "Type 2"? I can't |
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find reference to those designations via Google. |
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|
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- Grant |
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