Rich Freeman on 22 Aug 2012 13:14:52 -0700

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Re: [PLUG] Tried of Windows...

On Wed, Aug 22, 2012 at 3:06 PM, Sam Gleske <> wrote:
> On Wed, Aug 22, 2012 at 11:34 AM, Grabowy, Chris <>
> wrote:
> If you're using a special RAID controller (like
> me) then a lot of times the vendor will post Linux supported kernel modules
> (what you know as Windows drivers) for their hardware.

Most RAID controllers built into motherboards aren't really true RAID
controllers anyway.  Even PCI cards that you get for $50 with that
feature aren't true RAID.  It is all done via software.

Real RAID cards cost about $1k and usually have a battery-backed
cache.  They perform better and are safer if you have a power failure,
but if the card dies you'll probably never be able to read the drives
unless you get another of the same model/etc.

For any kind of home use I'd just use raid5 with mdadm.  It is way
more flexible than hardware raid, largely automagic, and the disk
format is stable so it will work ages from now.

Regarding OS - while I'd personally use Gentoo due to preference I
think the smartest move for you is to run Ubuntu LTS server edition.
You don't care about software on the thing - you just want it to work
and rarely need maintenance.  Ubuntu works on everything and is
basically plug-and-play from an install standpoint, and I'll take
apt-get over rpm any day (not that I use either much).  If you were
loading a datacenter full of racks of these things maybe I'd consider
CentOS, but my suspicion is that this is just going to be less

I would try to migrate that data to ext4 as already suggested.  I'm
not sure how much free space you have to play with, but if you can
manage to free an entire drive then the easiest way to migrate is to
convert one drive at a time and move data over.  You'll need more than
a full disk's worth of space if you want to covert to raid5.  That can
also be done in pieces.

For a raid5 conversion free up one drive completely.  Set up that
drive as a raid5 with a missing spare, and create a filesystem on it
(I'd stick lvm on there too).  Then move a disk's worth of data over,
and then extend the raid over the now-free drive (still keeping a
missing spare).  Repeat this until the last drive is copied over, then
extend the raid5 over that drive but not keeping a missing spare (the
last drive becomes your parity drive).  Note that until you completely
migrate if any single drive fails you lose everything, since you're
operating without parity.  If you have two drives worth of free space
then you can set up the parity drive from the start and drive loss
should not cause failure.  This migration will take days - copying the
data is slow, and reshaping a raid5 is slower.  You can do both while
the system is online, but it takes time (more time if your drives are
otherwise busy).

In general though if you can get your data onto raid5 + lvm you'll
find your storage will be much more flexible, and you will be
protected if a drive fails (but not from logical failures - you'll
need backups for that and that will be expensive at the multi-TB scale
- I don't try to back up all my media as a result).

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