Very different layout -- RE: How the Centos 5.0's kickstart initrd.img is build??

[Chris Edillon]

Guolin Cheng wrote:

>  I’ve tried run mkinitrd to create an initrd.img file for Centos 5 
> Kickstart, but it turns out that the default initrd.img is quite 
> different from the initrd.img file created with mkinitrd. Any one know 
> how to create a Kickstart initrd.img with custom kernel? Or the hacking 
> steps on a existing Centos 5 kickstart initrd.img?
> 
   yeah, all mkinitrd does from what i remember is look at your
existing machine's kernel module settings in /etc/modprobe.conf
and create an initrd.img with those settings, so you can boot
your machine with the proper drivers for your storage and network
devices.  the install initrd.img has much more functionality,
primarily centered around device discovery and kickstarting.
instead of trying to create a new install initrd.img, it's much
easier to modify the one that comes with the OS.  i posted
something to this list a few weeks ago detailing how to do so
with a RHEL3/4 box:

https://www.redhat.com/archives/kickstart-list/2007-May/msg00081.html

it should be much the same for RHEL5/CentOS5 unless they've
changed the format of an initrd.img, but that should give you
a good idea of where to start.

   as far as a custom install kernel, i haven't tried this before.
i imagine that as long as it calls the init program from the
initrd.img and all of the kernel modules you put in the initrd.img
are compiled against the custom kernel, you could use any kernel
you want.

chris