[techtalk] installing RAID controller on existing RedHat 6.2 system

[David Merrill]

Naomi Hospodarsky wrote:
> 
> hey folks,
> 
> Anyone have any tips regarding taking an existing RedHat 6.2 server and
> adding a RAID controller to it?
> I've got the driver loading (I think) but when I boot, I only see my
> original disk. How do I tell RH that there's a whole new giant space that
> it can use now?
> I can't seem to find any reference that the system is acknowledging the new
> array...
> 
> Or do I have to reinstall everything??
> 
> I've never done RAID on Linux before....at least not to a pre-existing
> system...
> If it matters, I've got the Adaptec 2100s PCI controller.
>   Anyway, any tips at this current too-much-coffee-woman hour would be much
> appreciated....

If you haven't yet, check out the HOWTOs at the LDP. We have the
following HOWTOs on RAID arrays:

Boot+Root+RAID+LILO HOWTO
A cookbook for setting up root raid using the 0.90 raidtools for
bootable raid mounted on root using standard LILO.
http://www.linuxdoc.org/HOWTO/Boot+Root+Raid+LILO.html

DPT-Hardware-RAID-HOWTO
How to set up hardware RAID under Linux.
http://www.linuxdoc.org/HOWTO/mini/DPT-Hardware-RAID.html

Root-RAID-HOWTO
This document only applies to the OLD raidtools, versions 0.50 and
under. The workarounds and solutions addressed in this HOWTO have
largely been made obsolete by the vast improvment in the 0.90 raidtools
and accompanying kernel patch to the 2.0.37, 2.2x and 2.3x series
kernels. You may find the detailed descriptions useful, particularly if
you plan to run root raid or use initrd.
http://www.linuxdoc.org/HOWTO/Root-RAID-HOWTO.html

Software-RAID-HOWTO
How to use Software RAID under Linux. It addresses a specific version of
the Software RAID layer, namely the 0.90 RAID layer made by Ingo Molnar
and others. This is the RAID layer that will be standard in Linux-2.4,
and it is the version that is also used by Linux-2.2 kernels shipped
from some vendors. The 0.90 RAID support is available as patches to
Linux-2.0 and Linux-2.2, and is by many considered far more stable that
the older RAID support already in those kernels. 
http://www.linuxdoc.org/HOWTO/Software-RAID-HOWTO.html

Sotware-RAID-0.4x-HOWTO
How to use Software RAID under Linux. RAID stands for "Redundant Array
of Inexpensive Disks". For users of the Linux MD kernel extension, the
associated tools, and their use. This HOWTO addresses an earlier
implementation.
http://www.linuxdoc.org/HOWTO/Software-RAID-0.4x-HOWTO.html

It sounds like you want the Software-RAID-HOWTO. HTH,

-- 
David C. Merrill, Ph.D.
Linux Documentation Project
Collection Editor & Coordinator
www.LinuxDoc.org