Re: DIY NAS - raid/jbod questions

On 27 Oct, 10:58, Mike Tomlinson <nos...@xxxxxxxxxxxxxxxxxxxxx> wrote:
In article <16aa100b-1332-455a-9cdc-85df68838...@xxxxxxxxxxxxxxxxxxxxxxx
s.com>, Ric <infobub...@xxxxxxxxx> writes

What I want is multiple disks with failover, and I want to know that
should the motherboard and raid controller die in a couple of years, I
can read the contents of the disks independantly of the motherboard
hardware.

Don't use a hardware RAID controller then.  Use Linux software RAID.
It's just as good (if not better).

Real-life example: I took 4 PATA drives configured as RAID5 from a
failed machine to another one - completely different hardware, different
version of Linux - plugged them in in random order (not having made a
note of which drive was hda, hdb etc.) and on boot, the OS found the
RAID and mounted it quite happily.

Given I'd have 4 SATA bays, what's the best setup for this?  If I'm
going to do this, I want to do it right.

Is it at all possible for you to add another disk (in an adapter in a
5.25" bay?) for the OS and to devote the 4*SATA to the RAIDed data disk?
My experience has been that it's best to run the OS on its own disk(s)
and to keep the filesystems on RAIDed disks fairly simple.  

Linux SW raid does seem like the way forward. In your example I'm
presuming you booted the old system's disks in a new linux build using
that new system's boot drive, with the RAID disks added as a separate
array?
If I used FreeNAS I could boot the OS off USB pendrive, or hook up a
small IDE HDD to the spare IDE controller and use that, and have the 4
disks available as data only. However, all the Atom-based Mini ITX
boards I've seen only have 2x sata ports, so I'd need a PCI->4x SATA
card - i.e. a hardware RAID controller.
Reckon I could use one of these in non-RAID mode - i.e. just as adding
4 sata ports to the mobo and let FreeNAS or similar worry about the
software RAID?

The Intel atom-based mini-itx boards are under 50 quid these days for
board and CPU which seems a very good deal.
Eg http://www.microdirect.co.uk/(38027)Intel-Motherboard-D945GCLF-945GC-LGA775-on.aspx
.

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