No RAID for VT8237?

[David O'Brien]

On Tue, Nov 30, 2004 at 11:09:34AM +0000, Bob Bishop wrote:
> You might try an 'atacontrol create <etc>'. I had a problem where I'd 
> defined RAID1 in the BIOS, but 5.3 wouldn't see it (specifically saw the 
> drives individually but no ar0); after atacontrol create... it all works. 
> Go fig.
 
This isn't weird.  By using 'atacontrol create' yourself, you have a
pure-software RAID same as you would have with ccd(4).  The difference
from defineing it in your software-assist "RAID" BIOS is that you can
boot off the RAID.  With the pure-software RAID you cannot[*].

[*] Unless your PATA/SATA "RAID" controller just happens to understand
the metadata used by 'atacontrol create'.  A 'atacontrol create' RAID1
(mirror) might also be bootable, I'm not sure about that; but a RAID0
(stripe) certainly isn't.

There are many new SATA "RAID" controllers that our ATA driver doesn't
yet understand the metadata.  Soren is working on support for these newer
chipsets.

-- 
-- David    (obrien at FreeBSD.org)