[CentOS] Installing on partitionable RAID arrays

Thu Mar 26 14:57:20 UTC 2009
Robert Heller <heller at deepsoft.com>

At Thu, 26 Mar 2009 08:44:34 -0500 CentOS mailing list <centos at centos.org> wrote:

> Ross Walker wrote:
> >> RedShift wrote:
> >>>
> >>> As a follow-up, I found the documentation I wrote how to install  
> >>> CentOS
> >>> without any installer:
> >>
> >> That looks useful.  Do you have any hints about how to get the right
> >> drivers installed if you wanted to build a disk to be moved to a
> >> different machine?
> > 
> > That's even easier.
> > 
> > Add the disk driver names in modprobe.conf the ones for system disks  
> > in the top half, data disks below. Then run a mkinitrd.
> > 
> > Modprobe.conf excerpt:
> > 
> > alias scsi_adapter ata_piix
> > alias scsi_adapter0 ahci
> > alias scsi_adapter1 mega_sas
> > alias scsi_adapter2 mpt
> > 
> > # mv /boot/init-$(uname -r).img /boot/init-$(uname -r).img
> > # mkinitrd /boot/init-$(uname -r).img $(uname -r)
> > 
> > That should make an initrd with the drivers necessary to boot your  
> > other boxes (of course using your own disk drivers and not mine).
> Thanks - but there is another half to that question. How do you find the 
> names of the drivers that match any particular hardware without running 
> the installer?

Installing the kernel source RPM is one option.  Then it is a matter of
the use of grep to search in the source code for the devices you need
drivers for.

You can also 'cheat' by copying the PXE boot initrd file from the first
CD or the DVD and unpack this file.  It is a compressed cpio file:

gunzip  < /path/to/pxeinitrd|(cd /some/temp/directory;cpio -i)

In the /some/temp/directory there will be a subdir named modules, with a
file named modules.alias.  This file contains a mapping of PCI
vendor/device IDs to module names.  lspci will give you the
vendor/device IDs of the devices in question or you can look them up in

> I'd like to have a generic backup/restore mechanism that would drop in a 
>    tar image (etc.) from one machine and come up running on something 
> different - or a fixup procedure for disks that have been moved from one 
> chassis to another.  Even where the machines are identical and I put the 
> target machine's MAC addresses in the ifcfg-ethX file, something seems 
> to rename them and screw things up when a disk is moved.

Robert Heller             -- 978-544-6933
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