mpi/mpii cards that do IR/IS or IM should do RAID 1 just fine and are
supported by bioctl.  You just have to purchase the card carefully and
make sure it has one of those acronyms.

A bit more expensive would be mfi but those are well supported.

What I don't know much about but is cheap are the areca cards.  Some
people swear by them; I simply haven't used them so I have no opinion.

On Mon, Nov 15, 2010 at 06:30:18PM +0100, md@mdaniel.de wrote:
quoted text
> I have a hard time finding a RAID1 capable controller that is well
> supported via bioctl, available, and not too expensive.
> Is there e.g. a nice mpi or mpii card that can be controlled via bioctl?
> The man page only mentions that some mpi cards offer Raid1. Of course
> it doesn't have to be a mpi card.
> This PCI-e card would be used with Sata disks on the i386 architecture
> (OpenBSD 4.8).
> 
> Thanks.
> 
> Background:
> -----------
> I could do /var on softraid together with altroot but I seek the
> convenience of RAID1 to be able to select when to reboot in case
> of disk failure.
> I am fully aware that RAID is no backup concept and that now the
> controller becomes a single point of failure.
> Maybe the controller that you recommend will have the additional
> benefit of allowing me to attach a disk to a standard Sata controller
> in case of RAID controller failure? Otherwise I am prepared to order
> two identical controllers to mitigate this problem.
> 
> Please feel free to point out any error in my thinking and don't hesitate
> to mention if I should implement a different set up.
> It is probably unavoidable that my desire for cheap raid hardware will
> not be met with unconditional approval ;-)
> 
> Cheers,
> 
> Marcus