On Thu, Jun 29, 2006 at 11:24:25AM +0200, josen@xenon-nrw.net wrote:
> Hello list!
> I'm looking into buying hardware for a RAID5. The system I have spare is
> an Athlon XP 2500, 1.5G memory, PCI-architecture, one fxp and one em
> network cards.
>
> The system will be used for backing up my personal stuff (since age nine)
> and for storing large amounts of data.
>
>
> I've already read about RAIDframe in OpenBSD and want to use it. So far,
> as I understood I now just need some SATA-Card(s) and three plus one spare
> harddisks to get going.

RAID5 requires n+1 disks, where n is the number of disks you actually
use; you can, if you really want, add some spares. Spares are used to
rebuild the array if one disk fails; if a spare is not available when a
disk fails, the array runs in degraded mode - i.e., it works, but it has
no redundancy, any failed disk will lead to data loss.

RAIDframe works quite well, but especially before -current, be careful
about poking it - poking it too much used to lead to panics (I've had a
couple of weird problems when first configuring the disk; for maximum
security, a RAID set should be configured only once between reboots).

Once it works, though, you'll be happy with it. I know I am.

> My big problem is in selecting which SATA-Card (I've only used Dawicontrol
> on OBSD) and if I should buy one with four ports or two with two ports.
>
>
> What do you use in production?
> Which aspects of the system need the most attention?

I use a couple of very, very old disk off a double IDE controller. It
works well, and has saved me from rebuilding my system twice (two disk
crashes, yes they are *very* old). It's not fast, of course, but that
was never a design goal. It *is* free (the disks were old spares and a
couple of gifts), and *does* safeguard my data (in conjunction with good
backups), which *was* the design goal.

As to SATA cards, no clue.

joachim