[CentOS] Centos and Software RAID

[Mark Schoonover]

Barry L. Kline <mailto:blkline at attglobal.net> tapped at Friday, May 26, 2006
2:56 PM:

> Erick Perez wrote:
>> I purchased an Intel D945GNT motherboard and it comes in the BIOS
>> with an option to create a RAID 0 or RAID 1 volumes using my
>> existing two SATA disks. However when installing Centos 4.3 x86_64 I
>> see the the installer recognices the two drives and does not "see"
>> the RAID 0. 
>> Is that ok?
>> Should I disable the RAID in the BIOS and then go for a LVM+RAID 0
>> setup in the installer ? Since it will be a server machine I want to
>> gain the performance of RAID 0 without too much complications (i
>> will use ext3 instead of ReiseFS)
> 
> Hi Erick.
> 
> It's doubtful that your on-board RAID controller is going to work with
> Linux.  Most of the on-board controllers are really nothing more than
> two SATA channels with the driver (for Windows) providing the RAID
> functionality.  Thus, you're really not gaining hardware RAID, in
> spite 
> of what you are led to believe by the BIOS options.  That's why Linux
> is 
> reporting it as two drives.
> 
> You have two choices:  1) Buy a hardware RAID controller (my choice
> being the 3ware brand), or 2) use software RAID.  Since that's what
> you'd be getting anyways if you were using this board with Windows and
> the appropriate driver, you're not losing anything.
> 
> FWIW I've had no problems whatsoever when using software RAID. I use
> it 
> on many of my servers.


I'd like to know how things went with software raid when you've lost a drive
in a mirror or RAID5. The times that's happened to me, I could never recover
the partition - had to always restore from tape. After that point, it was
hardware only. Software RAID works fine, as long as there's no problems.

Mark