What is the minimum number of disk drives you can have in a RAID 10 array? I have read you must have at least four, but our server admin said it is HP's default, and he can do it on just two drives. This is on a Window Server 2003 with a total of four 72 gigabyte (GB) drives in the server and 11 36 GB drives external.
The minimum number of disk drives needed for RAID 10? This depends on the storage array vendor's firmware. RAID 10 configurations can be accomplished by mirroring a stripe set, or striping a mirror set. When you stripe a mirror set (my preferred method due to resiliency), you first create two mirror sets and then create a stripe set from the two mirrors (minimum four drives), when you mirror a stripe set, you first create two stripe sets (usually of at least three drives each) and then mirror them to another stripe set (total of six drives).
I have not personally heard of creating a RAID 10 set from two drives, since two drives are the minimum for a simple mirror.
More on raid 10 minimum drives:
Double drive failures in a RAID 10 configuration
RAID 10: Two great RAIDs that go great together
Dig Deeper on Storage management and analytics
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