deploy:
docker installation
https://docs.docker.com/install/linux/docker-ce/ubuntu/
Overlay installation and introduction
http://techblog.d2-si.eu/2017/04/25/deep-dive-into-docker-overlay-networks-part-1.html
http://techblog.d2-si.eu/2017/05/09/deep-dive-into-docker-overlay-networks-part-2.html
https://www.cnblogs.com/bigberg/p/8521542.html
The principle is explained in detail:
http://chenchun.github.io/docker/2015/12/29/km-docker-overlay