CentOS - Feb 2006 - Help with megaraid_mbox driver

Hi All,

I've built a custom CD based on CentOS 4.2.  An OOB CentOS 4.2 disk will 
detect the megaraid (Perc4) card in a Dell 1850/2850, and load properly. 
  My version does not.  I have checked, and the original shipping kernel 
for CentOS contains the same megaraid_mbox driver as the updated kernel 
that is on my CD.  Basically, my CD removed some RPMS, and added others 
for a custom distro.  As far as I can see, the proper kernel files are 
still present (I'm using an unmodified buildinstall script, and Johnny 
Hughes' build script for the CD).  Does anyone have any suggestions on 
how to figure out why the new CD says it cannot find an appropriate hard 
drive to install on?

Is there something specific that would be missing like pcitables, etc?

Thanks for any advice or suggestions.

-Scott

I'm going to say at the start that I might be completely wrong about 
this.  (And I may be confusing FC4 with CentOS.) But are you sure you 
aren't needing the megaraid.ko driver rather than the megaraid_mbox?

Not sure about install time, but for boot time, mkinitrd gets this wrong 
and I have to go in and copy the proper module (which is not in 
kernel/drivers/scsi/megaraid, but in kernel/drivers/scsi) into the lib 
dir of the initrd and then add:

insmod /lib/megaraid.ko

to the init script in the initrd.

Anyway this link *might* be of help:

http://www.tuxyturvy.com/blog/index.php?/archives/4-Installing-RHEL4-on-Systems-with-Legacy-Megaraid-Drivers.html

But have you considered the possiblility of using software RAID?  After 
all the problems (along these very lines) that the legacy PERC cards 
have caused me, I'm moving my servers to software RAID.

It depends upon your specific situation, of course, but it makes sense 
to consider the possibility.  For example, hardware RAID5 might be 
better if disk performance is critical, as RAID5 has a lot of processor 
overhead.  But for, say, RAID1, software RAID has some advantages.

-Steve