[rescue] Re: RAID level 6 - any experiences?

[Patrick Giagnocavo]

On Mon, Feb 25, 2002 at 08:03:36PM -0800, Robert Novak wrote:
> On Mon, 25 Feb 2002, Patrick Giagnocavo wrote:
> 
> > Already had the Mylex RAID controller. I understand that RAID6 can
> > handle more than one drive failure and keep going.  Does anyone have
> > any experience with this, or should I bite the bullet and go RAID 10?
> 
> I have to admit I've never heard of RAID 6 until now, but a web search
> found http://www.acnc.com/04_01_06.html for me (and I think I have a
> AC&NC tshirt that reads "Got Protection?" on the back). 
> 
> Which Mylex card do you have, and does it explicitly support RAID 6? This
> page says it has special expectations of the controller, and I haven't
> seen references to it on any of the software or hardware raid I can
> remember reading about.

It is a DAC960SX with 2 channels going to the disks (68pin SE) and one
channel to the host (68pin diff).  It explicitly supports it, since
the LCD panel I am using for configuration gave me that option.
 
Seems RAID10 is the way to go.  

Got any special prices on disks?  The disk shelf can take SCA 1.0 or
1.6 inchers.

> And on an aside, does anyone know of any available HVD RAID controller
> cards suitable for handling a pile of RSM217 arrays? I've got LVD/SE RAID
> controllers in PCI, standard HVD cards in PCI and SBus, and a source for a
> quad channel HVD card, but I'd really like something resembling "hardware"
> RAID for this stack of 28 disks.

I have come across a page which lists the DPT devices, since
discontinued:

PM3334UDW - PCI-to-Ultra/Wide Differential SCSI RAID Controller

PM3334UDW/2 - PCI-to-Ultra/Wide Differential SCSI RAID Controller with 2 SCSI busses

PM3334UDW/3 - PCI-to-Ultra/Wide Differential SCSI RAID Controller with 3 SCSI busses 

no indication on LVD or HVD though.  I have a sneaking suspicion that
they are LVD.

./patrick