Re: Mirroring

[Nick Holland <nick@holland-consulting.net>]

No, last I looked (2.7), ccd mirroring did not function (crashed upon
trying to use it).  (the spanning options seem to work just fine).

Even if that bug issue was resolved, ccd does _NOT_ strike me as
appropriate for a number of operational issues, such as the lack of an
automatic remirror on crash/powerfail/other unplanned downing. 
Strikes me as more "Mirroring so I can say its mirrored" not
"Mirroring to save my butt in the event of a drive failure".  Once I
realized that, I'm not eager to see resources spent on debugging this
"solution".

RAIDframe is a much more "ready for prime time".

Keep in mind, however, none of the software solutions for OpenBSD
mirror the boot partition, meaning if that is what fails, you are not
going to be able to reboot your system..or even operate your system
(depending upon what is on your boot partition).  This makes it of
questionable value, though far from being of no value.

If you want to do real mirroring, look at the hardware compatability
list for one of the RAID cards, or look at the "pure hardware" (i.e.,
software doesn't even know it is there) IDE mirroring solutions out
there:
   http://www.arcoide.com/   
or
   http://accordance.com.tw/araid-(1).html

I've used, tested (abused) and reviewed the ArcoIDE product, $250 USD
or so got the thing up and running, very well thought out product.  
http://www.sigmasoft.com/~openbsd/archive/openbsd-misc/200007/msg01199.html

The Accordance product was pointed out by someone else on this list, I
never did a hands-on with it (nor do I believe anyone else here
has)... I did track down a price on it once some time ago (wasn't
easy), I'm thinking it was around $500-$600 USD.

Before you ask: Forget the Promise and other "cheap" IDE mirroring
systems -- they are really 90% software and 10% BIOS -- there is no
real hardware mirroring, and they are not supported by OpenBSD now,
and no one has said "I'm working on it".  The effort to get one of
these working would be almost identical to the effort for a pure
software mirroring solution.

Nick.
(Geek with Nailgun)

joshp@ioactive.com wrote:
> 
> lo all,
> 
> it's been awhile, hey any suggestions on the correct method to mirror
> partitions under obsd ( RAID0 ) ?
> 
> is ccd the correct path to go down to accomplish this?
> 
> thanx in advance,
> 
> josh

-- 
http://www.holland-consulting.net/