Re: 3Ware RAID Controlers

From: KR (kristian.rasmussen_at_broadpark.no.spam.com)
Date: 08/25/04 

Date: Wed, 25 Aug 2004 21:03:03 +0200

Leo wrote:
>
> I'm a little bit confused about the 3Ware Raid Controllers. They are said to
> be true hardware based RAID controlers.
> But why does the linux kernel need a driver to handle the controller?
> I thought that with a hardware based RAID controler the operating system
> doesn't even know about the
> existence of the RAID - it thinks of one big HD. Is this correct?

RAID or not, you ALWAYS need a driver for any controller. Even standard
ATA/EIDE controllers need drivers, it's just that you don't hear much
about it, because the drivers are usually bundled with the OS.

3Ware controllers are indeed "real" hardware raid controllers, and the
OS does see the RAID array as one big HD (usually a SCSI HD, even though
the RAID may consist of ATA or SATA drives). The RAID algorithms and
array management functions are all done by the controller chip, not the
driver.

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