bootup ubuntu-server-14.10 from pxe

step 1.
download netboot
wget -r --no-parent http://archive.ubuntu.com/ubuntu/dists/utopic/main/installer-i386/current/images/netboot/

step 2,
move netbook to /tftpboot/

step 3,
update /etc/dhcp/dhcpd.conf

subnet 192.168.32.0 netmask 255.255.255.0 {
  range 192.168.32.2 192.168.32.254;
  option routers 192.168.32.1;
  option domain-name-servers 192.168.32.1;
  filename "/netboot/pxelinux.0";
}

step 4.
power on the PC and choose boot from pxe option.

that's almost all.