Subject: Re: RAIDFrame or CCD? (WAS Re: ccd0c weirdness)
To: Mocha <netbsd_alpha@yahoo.com>
From: Todd Whitesel <toddpw@best.com>
List: port-alpha
Date: 03/08/2000 21:51:43
> so i can't lump a bunch of drives together (same size etc) and make one 
> huge virtual drive with raidframe?

Hold on -- both Raidframe and ccd can do the "huge virtual drive" thing,
as long as you also want "striping" (data spread evenly across the disks
for better performance).

However, ccd also offers plain "concatenation", which is when the disks
are just placed one after another to create the virtual drive. It won't be
any faster, but you have more control over where things go on each disk.

Plain "concatenation" is mainly used in small configurations where you
just need to trade a little space between one disk and another. For any
large setup or performance-oriented application, you want "striping" and
either of ccd or Raidframe can be used. Here, the main difference is that
Raidframe can also use extra disks to provide error recovery if one disk
goes bad or is stolen, but ccd cannot.

(I'm nowhere near an expert here, everyone please jump in if I have
misrepresented something...)

Todd Whitesel
toddpw @ best.com