From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Rowe <rowe@excc.ex.ac.uk>
Subject: Two-disk RAID5?
Date: Wed, 26 Apr 2006 17:41:47 +0100
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I'm about to create a RAID1 file system and a strange thought occurs to
me: if I create a two-disk RAID5 array then I can grow it later by the
simple expedient of adding a third disk and hence doubling its size.

Is there any real down-side to this, such as performance? Alternatively
is it likely that mdadm will soon be able to convert a RAID1 pair to
RAID5 any time soon? (Just how different are they anyway? Isn't the
RAID4/5 checksum just an OR?)

Thanks

John