anchor.diff:  #
   #
   
  +# put COPY . . the end of Dockerfile for speedup build time by maximum cache usage
  +COPY . .
  +
   # Clean up APT when done.
   RUN apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
  
positive.code: CMD [ "start" ]
  
  WORKDIR $ACROSSFW_HOME
  COPY . .
  RUN ln -s /etc/service /service \
    && ln -s ${ACROSSFW_HOME}/service/vpnet /service/vpnet
  
  
negative.code:     	iptables \
      	net-tools \
      	netcat \
      	shellcheck \
      	tcpdump \
      	tinc
  
  