On September 8, 2006 5:59:47 PM -0700 Richard Elling - PAE
<[EMAIL PROTECTED]> wrote:
Ed Gould wrote:
On Sep 8, 2006, at 11:35, Torrey McMahon wrote:
If I read between the lines here I think you're saying that the raid
functionality is in the chipset but the management can only be done by
software running on the outside. (Right?)
No. All that's in the chipset is enough to read a RAID volume for
boot. Block layout, RAID-5 parity calculations, and the rest are all
done in the software. I wouldn't be surprised if RAID-5 parity checking
was absent on read for boot, but I don't actually know.
At Sun, we often use the LSI Logic LSISAS1064 series of SAS RAID
controllers
on motherboards for many products. [LSI claims support for Solaris 2.6!]
These controllers have a builtin microcontroller(ARM 926, IIRC),
firmware,
and nonvolatile memory (NVSRAM) for implementing the RAID features. We
manage
them through BIOS, OBP, or raidctl(1m). As Torrey says, very much like
the A1000.
Some of the fancier LSI products offer RAID 5, too.
Yes, some (many) of the RAID controllers do all the RAID in the hardware.
I don't see where Ed was disputing that.
But there will always be a [large] market for cheaper but less capable
products and so at least for awhile to come there will be these not-quite-
RAID cards. Probably for a very long while.
winmodem, anyone?
-frank
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