Mine

ddns-update-style ad-hoc;
deny unknown-clients;
server-identifier 192.168.0.1;

group {
        next-server 192.168.0.1;
        filename "/boot/pxeboot";
        option root-path "192.168.0.1:/exports/freebsd70/";

        host nasbox { hardware ethernet 00:30:48:90:57:32; }
}

subnet 192.168.0.0 netmask 255.255.255.0 {
        range 192.168.0.10 192.168.0.64;
        option routers 192.168.0.1;
}