post_install() {
  cat << EOF
   
    Mininet requires Open vSwitch to be running in order to
	instantiate switches. To run it, just execute the following
	commands (as root or using sudo):
   
      # systemctl enable ovsdb-server.service
      # systemctl start ovs-vswitchd.service
      # systemctl enable ovsdb-server.service
      # systemctl start ovs-vswitchd.service

EOF
}