2014.01.31 This script only handles single port ( EXT_PORT, INT_PORT) now.
 '--match multiport --dports xxx' is replaced by '--dport xxx' because the former does not seem to support single-port.
2014.01.31 This script only handles single port ( EXT_PORT, INT_PORT) now.
'--match multiport --dports xxx' is replaced by '--dport xxx' because the former does not seem to support single-port.