[CentOS] Netcell RAID cards -- 2.6.12.3+ (or 13.2+?) ATA has NetCell support

Sat Dec 10 03:43:57 UTC 2005
Paul <subsolar at subsolar.com>

On Thu, 2005-12-08 at 18:29 -0800, Bryan J. Smith wrote:
> Ugo Bellavance <ugob at camo-route.com> wrote:
> > Anyone tried netcell products
> 
> NetCell's RAID-XL is basically a fixed 32-bit (2+1 drive) and
> 64-bit (4+1 drive) [S]ATA RAID-3 implementation.  Before I
> talk more about how RAID-XL works, let's talk RAID-3.
> 
> RAID-3 and RAID-4 use striped data with dedicated parity,
> whereas RAID-5 uses striped data and parity.  RAID-4 and 5
> stripe large blocks, so multiple access could be possible
> (reducing latency), whereas RAID-3 writes sectors immediate
> and [virtually] parallel to all disks.
<SNIP>
> Since the NetCell is designed for desktops and direct I/O, it
> doesn't make sense to use a traditonal SCSI driver.  There
> are no real services, queuing, etc...  It's really best as a
> "dumb block ATA device" that is written to and read from
> directly.  That's why it was designed to show itself as a 1
> or 2 device ATA channel.
> 
> > I'd like to know if it would be possible to install 
> > CentOS directly on drives on such a card, without needing a
> > build box...
> 
> You'd have to rebuild the installer with a newer kernel like
> 2.6.12.3.  I had tried to patch the ATA support in before,
> and it was a bit of a PITA.  But I am running my SR5000 card
> in a Fedora Core 4 test system, using five (5) Seagate 7200.8
> 200GB drives.  Thing moves data like I've _never_ seen.
> 
> I'm using my SR5000 for a prototype multimedia server in my
> house.
> 

I was looking at them as a cheaper alternative to a 3ware cards for my
MythTV/file server with an array of three drives. The problem with the
NetCell cards not having a monitoring tool to tell if a drive fails
makes it much less attractive.

Maybe they will release the tools by the time CentOS 5 comes out and I
can migrate from FC2 to that ... maybe V4L with be built in EL5 by that
time.

Paul