Installing onto RAID

[bscott at ntisys.com]

On Tue, 17 Sep 2002, at 5:03pm, pll at lanminds.com wrote:
>>> I want to mirror all the file systems on all 4 drives ...
>>
>> AFAIK, this is not supported in the Linux "md" driver.  It should be
>> pretty easy to do, but it has not been done.
> 
> Actually, it does work.  It may not be officially supported, I don't know,
> but I know it's currently being used.

  Really?  You mean, in your raidtab file, you can have a "raid-level" set
to 1 with a "nr-raid-disks" greater than 2?  That's neat.  Or do you just
mean mirroring two already-mirrored "md" devices (which occured to me after
I sent my original message)?

> I know the kernel also needs "autodetection" enabled, however I can't 
> seem to find that option in the kernel config.  Anyone know where 
> that is?

  Looking at the 2.4.18-3 sources that shipped on my RHL 7.3 box, it appears
that RAID autodetect is always on, unless explicitly turned off (with the
"raid=noautodetect" kernel option).  Check out the drivers/md/md.c file, and
search for the string "autodet".

-- 
Ben Scott <bscott at ntisys.com>
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