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This is a patch used to create EL6 images which will boot with the root file system in memory.

Building the image

Install livecd-tools

$ sudo yum install livecd-tools

Download the kickstart file (centos64-pxe.ks), or create your own

Create the iso file:

$ sudo livecd-creator --config=centos64-pxe.ks --fslabel=centos64-pxe
$ sudo livecd-iso-to-pxeboot centos64-pxe.iso

This will output the files vmlinuz0 and initrd0.img. Make these files available on a web server.

Booting on the image

This is an example iPXE script. Modify it to match your setup:

#!ipxe
initrd http://example.com/initrd0.img
kernel http://example.com/vmlinuz0 initrd=/initrd0.img root=/centos64-pxe.iso rootfstype=auto rw liveimg toram size=4096
boot