Selecting NFS home via %pre section

[Coe, Colin C.]

Hi all

I want to select a different NFS install path depending on options
passed through PXELINUX.  Something like:

pxelinux.cfg
------------
label el3_lws_safe
        kernel el3u5_x86_64/vmlinuz
        append ksdevice=eth0
ks=nfs:a.b.c.d:/export/install/rhel_x86_64_testing.cfg load_ramdisk=1
initrd=el3u5_x86_64/initrd.img
        ipappend 1


ks.cfg
------

lang en_US
langsupport en_US
keyboard us
mouse genericwheelps/2
timezone --utc Australia/Perth
rootpw --iscrypted <snip>
reboot
install
%include /tmp/nfs.cfg
bootloader --location=mbr

%pre

#!/bin/sh -x

for I in `cat /proc/cmdline`; do 
   echo $I | grep -q initrd && P=`dirname \`echo $I | cut -d= -f2\``
Done

echo "nfs --server=a.b.c.d --dir=/export/install/${P}" > /tmp/nfs.cfg

---

However, when I do this, anaconda asks for the install type (CDROM,
harddisk, ftp, nfs, etc) and refuses to use NFS.

Is this possible?  Is anyone else doing anything similar?

Thanks

CC