Heterogenous, dynamic RAID for a home server

[Ira Abramov]

Hey people,

A friend of mine want to build a file server machine at home to get the
benefits of a Drobo, but for 1500 NIS rather than $1500.

The idea is to mix in 1T, 2T and 3T disks he already has, and on
occasion grow the ׁ•torage by another disk or replace and rebalance it.
He wants it to be more reliable than RAID0 but more efficient than
RAID10, so RAID 5/6 are more like it.

I looked around at the idea of ZFS or a distributed FS on a single node,
but they are not options. I'm thinking how to do it with a block
redundancy scheme, and so far I came up with this: create a RAID5 from
the lower 1TB of all the disks you have, then a smaller RAID5 array from
the second TB, and finally a RAID1 or RAID5 from whatever you have left.

so if we say I have 2*3T and 2*2T and 1*1T, I have (5-1)*1T+(4-1)*1T+1T
(the last is RAID1). now I have 8TB in three block devices, and I make a
single LV (LVM2) from three extents.

Is there a better solution? do note that it's not optimal for spindle
activity, but this is a home machine serving two other computers and a TV
streamer at the worst case.

Any feedback is welcome...

-- 
Perishable item
Ira Abramov
http://ira.abramov.org/email/