[CentOS] centos 5.5 install + intel raid

Thu Jan 6 20:40:54 UTC 2011
John R Pierce <pierce at hogranch.com>

On 01/06/11 11:11 AM, Gene Brandt wrote:
> Thanks for that bit of advice. I've never been able to recover from 
> hardware raid on any Intel system. The software raid is simple to 
> configure and it works!

its not actually hardware raid.

when you set the 'raid mode' in the BIOS, at power up it sets a bit in 
the ICH chip which changes its PCI DeviceID from 'regular SATA 
controller' to 'Intel Matrix FakeRaid'.    thats *ALL* it does, change 
the device ID. no other hardware changes.    the controller is still a 
plain old multiport SATA controller.

the device ID is used to pick which driver by the OS plug-n-play 
stuff.   the regular setting choses the regular SATA driver while the 
'fakeraid' setting loads the fakeraid driver (dmraid in Linux).    the 
fakeraid driver implements all the raid in the device driver.    This is 
only really useful for MS Windows non-Server distributions which don't 
support native mirroring or whatever in the OS.