fc10 and raid-10

[Bill Davidsen]

Jeroen van Meeuwen wrote:
> Stuart Sears wrote:
>> Jeroen van Meeuwen wrote:
>>> Bill Davidsen wrote:
>>>> The Fedora installer has insisted on requiring four drives for raid-10
>>>> install, and then not using raid-10, but rather raid-1+0 which is
>>>> *NOT* the same thing.
>>> http://en.wikipedia.org/wiki/RAID#Nested_levels
>>
>> ah, but...
>>
>> http://en.wikipedia.org/wiki/Non-standard_RAID_levels
>>
>> See the Linux MD RAID 10 section.
>> (or man md, if you'd prefer)
>>
> 
> Ah, that RAID-10 ;-)
> 
> It's naming is a little confusing; RAID-10 (as used by the installer) is 
> what the installer uses to create RAID-1+0 (commonly referred to as 
> RAID-10, but indeed just "mirroring a stripeset" (1+0), but in one 
> single layer (10)), and hence requires 4 disks.
> 
> There's no RAID-10 in the installer as you refer to just like there is 
> no RAID LVM configuration, and whatnot. The installer is a helper 
> program to make the initial configuration for a new installation a 
> breeze, not to make sure it has every little checkbox for every possible 
> option.
> 
> If this isn't the appropriate configuration for you, then maybe 
> switching to the console on tty2 and creating the MD yourself or 
> providing a kickstart file with the correct %pre script solves the problem.
> 
The problem is that there is a "raid10" entry in the raid part of the installer. 
And since this is being done by the software raid, it's confusing to have raid10 
mean one thing to the installer and another in the man pages and to the man who 
maintains the code. I would like raid10 to be raid10, I would settle to have the 
installer call it raid1+0 to use the correct terminology.

> Don't get me wrong, it *could* be a very nice feature to add to the 
> installer, but then again we *must* prevent the installer from being 
> obfuscated for normal users.
> 
My point exactly, if the raid10 in the installer doesn't mean the same thing as 
the raid code and the raid man pages, it confuses the hell out of the users. Not 
to mention that there's no clean way to get to the raid10 supported by the 
kernel, which allows any number of drives >1, and considerably better 
performance with -f2 used for swap.

-- 
Bill Davidsen <davidsen at tmr.com>
   "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot