There are some customizations that the user community has made to Fog which allows you to specify which partitions to upload and deploy, but it is NOT built in to the base product.

I know there is a wiki article or a forum thread about how to do this, so look around.

unless you are just tied to fedora for some reason, install ubuntu 10.04 Server LTS and you can follow the instructions in the wiki article. I do not use Fedora currently, and I have no idea how to customize dnsmasq to do what it needs to do without the Ubuntu LTSP stuff.