Subject: Re: RAID
To: Jamie Downs <egon@peter.atw.earthreach.com>
From: Michael L. VanLoon -- HeadCandy.com <michaelv@MindBender.serv.net>
List: current-users
Date: 07/23/1997 14:08:35
>I can't find anything about RAID from the pages.  What RAID solutions are
>possible?  I'm looking at both hardware and software solutions, and am 
>considering the Mylex DAC960PD/Ultra, and looking at the Adaptec cards
>including the 2940UW.  Someone claimed that the 3940U and the 3940UW would
>do hardware raid, but the Adaptec specs don't list anything.  Any help would
>be appreciated.

Software RAID is done via the "ccd" driver in NetBSD.  It works
extremely well.

It isn't as automatic to setup as something like NTFS striped volume
sets.  On the other hand, like everything Unix, it gives you
infinitely more control over the details, so you can tweak it to your
heart's content.

Others have used hardware RAID devices successfully, as long as it
appears as a SCSI device, and you use a standard SCSI controller.  I
think the Mylex device you are desribing is one of those.

Currently, no controllers are supported that do RAID on the card (like
the Adaptec or DPT models).  The Adaptec 3940* cards do work very well
as standard multi-channel SCSI controllers, however, and can be a
really excellent way to drive a multi-drive multi-channel ccd array.

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  Michael L. VanLoon                           michaelv@MindBender.serv.net
        --<  Free your mind and your machine -- NetBSD free un*x  >--
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