[CentOS] RAID support in kernel?

Mon Jan 31 09:16:49 UTC 2011
Kenni Lund <kenni at kelu.dk>

2011/1/30 Michael Klinosky <mpk2 at enter.net>:
> Robert wrote:
>> You are generally *better off* to *disable* the motherboard RAID
>> controller and use native Linux software RAID.
>
> After my research, I'm realizing that linux doesn't quite support it.
> So, I'll probably do as you suggested.

I don't know if "linux doesn't quite support it" is true, but
nevertheless, even if Linux/CentOS had PERFECT support for it, you
still shouldn't use it IMHO.

The whole point of RAID is to give some sort of protection against
hardware (HDD) failures. Fakeraid is a proprietary software RAID
solution, so if your motherboard suddently decides to die, how will
you then get access to your data? You'll need another
motherboard/system with a fakeraid compatible controller, but how will
you know if the new fakeraid-based controller is compatible with your
HDDs created with the old controller? How will you know if the RAID
controller has the correct firmware? Your best bet is to buy exactly
the same motherbord (if it's still available at that time) and put the
same BIOS version on it as your old board had.

Using Linux software RAID, you'll get the same performance as fakeraid
and you can plug your HDDs into any motherboard running Linux to
access your data. Linux own implementation of software RAID was
introduced in kernel 2.1 (somewhere around ~1997), so you can be
fairly sure that the solution is well tested - something which is most
likely not the case with a fakeraid controller with limited/partly
missing Linux support.

The only valid reason to run fakeraid I can think of, is if you're
going to run Windows on it.

Best regards
Kenni