From mboxrd@z Thu Jan  1 00:00:00 1970
From: George Shuklin <george.shuklin@gmail.com>
Subject: how to get 'peer disk' in raid configuration?
Date: Thu, 28 Jun 2012 03:51:05 +0400
Message-ID: <4FEB9C69.9060608@gmail.com>
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Few days ago met intersting question:

Let assume we have RAID10 on 4 disks. We want to remove two  disks 
without  breaking array.

How we can know which drive is safe to eject? For 1st drive it obvious: 
any of. Second is more complicated: we need eject mirror part of 'second 
pair'.

How we can know exact topology of raid? (--detail does not provide 
enough information, IMHO).