Is it possible to create one ISO with one kickstart file that will work correctly when written to CD/DVD and as a USB?
As far as I can tell I need two separate versions as modifications are needed in isolinux.cfg (ks=) and ks.cfg (because I access the install media in %post)
It seems odd isolinux.cfg doesn't default to the root of the installation media and that kickstart doesn't have a global define for the source media device.
Or is there an alternative to kickstart?
Pull the kickstart file off a web server on your local network.
ks=http://192.168.1.201/f17-ks.cfg
(It's highly unlikely that you don't have a web server on your local network...)
If you have to install lots of systems, consider using Spacewalk.
It's not possible. USB need syslinux to be bootable. The source installation device is different too as you can see below.
Boot parameter:
CD/DVD use "repo=cdrom:<device>" while USB use "repo=hd:<device>:/<path>".
ks.cfg file :
CD/DVD use "cdrom" . USB use "harddrive --partition=hdb2 --dir=/tmp/install-tree"
