iptables tee 模块
https://blog.gnuers.org/?p=740
http://blog.csdn.net/wesleyflagon/article/details/38588507
tcpcopy： 没试过，不知道这玩意行不行。
https://github.com/session-replay-tools/tcpcopy
其他：
http://blog.csdn.net/dog250/article/details/17486031
直接bridge。。。
------------------ update @ 20170629 -------------------------
我找到了新方法：
http://backreference.org/2014/06/17/port-mirroring-with-linux-bridges/
https://adamkuj.net/blog/2016/05/18/pro-tip-port-mirroring-in-linux/
man tc
第二个方法： deamonloger
https://sourceforge.net/projects/daemonlogger/
参考 http://backreference.org/2014/06/17/port-mirroring-with-linux-bridges/ 后一部分。
/home/tong/Src/thirdparty/daemonlogger-1.2.1 [tong@T7] [17:01] > sudo ./daemonlogger -i lan0 -o tap-dpdk-1