[CentOS] 4.4/64-bit Supermicro/ Nvidia RAID [thanks]

Tue Dec 5 19:26:51 UTC 2006
Karl R. Balsmeier <karl at klxsystems.net>

Aleksandar Milivojevic wrote:

>Karl R. Balsmeier wrote:
>>I am installing Centos ServerCD 4.4 64-bit on a new Supermicro board,
>>the RAID BIOS looks fine, RAID 5, all 4 Seagate ES 250 GB drives show up
>>as a single array in the RAID BIOS tool, and the OS install phase
>>completes without a hitch.
>As others pointed out, the hardware you have has no RAID controller.
>It's just fake-RAID BIOS thing.  Linux sees your hardware as what it
>really is.  An ordinary SATA controller with 4 individual drives
>attached to it.  That's why it loads sata_nv driver (which is correct
>driver for your hardware).
>The reason why booting fails is most likely due to the fact that your
>BIOS is attempting to emulate (in software) RAID-5 volume when loading
>boot loader, kernel and initrd image.  While in reality those are
>probably stored on your first drive.
>Simply disable fake-RAID in BIOS.  You might not even need to reinstall.
>If you choose to reinstall, and want everything on RAID-5:
>- disable fake-RAID in BIOS (let it be what it is, SATA controller with
>4 individual drives)
>- create two small partitions (around 100MB) on first two drives.
>Configure them as Linux software RAID-1.  Use it as /boot
>- use remaining space on all four drives as one big partition, create
>Linux software RAID-5, use that as physical volume, carve logical
>volumes for rest of your system out of it.
>There's also a project that uses device-mapper and an user space utility
>to support fake-RAID functionality in BIOS.  Basically, the user space
>utility reads out fake-RAID metadata and configures device mapper.
>However, this is still not something you would get working out of the
>box.  You'd need to manually hack scripts in initrd image and add user
>space utility to it.  Also, I don't think it would work with RAID-5.
>RAID-0, RAID-1, RAID-10 configurations might work.
>>bonus/ p.s. -anyone had any experience with the Nvidia onboard RAID/
>>Supermicros?  Did you like it, (I'm an LSI-Logic fan myself), just
>>looking for opinions...
>Well.  It is not RAID.  Just an ordinary SATA controller.  See above.
disappointing, but it's true.  Supermicro verified what all of you 
said.  And since I'm not very interested in software RAID, i'll be 
dropping a hardware RAID card in and let my vendor know not to try and 
sell any more of these to those intending to use a Linux OS.

I'll try out your software RAID steps to give me something to play with 
till the hardware card shows up, since they are very clear and concise.  
Maybe it'll soften the empty 'no hardware raid5' feeling one has at present.