bin/166589: atacontrol(8) incorrectly treats RAID10 and 0+1 the same

[Allen Landsidel]

The following reply was made to PR bin/166589; it has been noted by GNATS.

From: Allen Landsidel <landsidel.allen at gmail.com>
To: Alexander Motin <mav at FreeBSD.org>
Cc: bug-followup at FreeBSD.org
Subject: Re: bin/166589: atacontrol(8) incorrectly treats RAID10 and 0+1 the
 same
Date: Tue, 15 Jan 2013 11:26:43 -0500

 Holy crap.
 
 The PR is about hardware raid controllers and their interface with 
 atacontrol, not ataraid.
 
 On 1/15/2013 11:25, Alexander Motin wrote:
 > At what point have we talked about hardware RAID controllers? ataraid(8)
 > never controller hardware RAID controllers, but only Soft-/Fake-RAIDs
 > implemented by board BIOS'es during boot and OS drivers after that.
 >
 > On 15.01.2013 18:22, Allen Landsidel wrote:
 >> Your solution then is to require everyone use software raid on their
 >> hardware raid controllers?
 >>
 >> On 1/15/2013 11:20, Alexander Motin wrote:
 >>> On 15.01.2013 18:03, Allen Landsidel wrote:
 >>>> I'm also extremely interested to hear how you intend to "handle it as
 >>>> RAID10 at the OS level" since that is, in fact, impossible.
 >>> Easily!
 >>>
 >>>> If it's a RAID0+1 in the controller, than it's a RAID0+1. Period.  The
 >>>> OS can't do anything about it.  A single disk failure is still knocking
 >>>> half the array offline (the entire failed RAID-0) and you are left with
 >>>> a functioning RAID-0 with no redundancy at all.
 >>> ataraid(8) in question (and its new alternative graid(8)) controls
 >>> software RAIDs. It means that I can do anything I want in software as
 >>> long as it fits into existing on-disk metadata format. If RAID BIOS
 >>> wants to believe that two failed disks of four always mean failed array
 >>> -- it is their decision I can't change. But after OS booted nothing will
 >>> prevent me from accessing still available data replicas.
 >>>
 >>>> On
 >