ZooKeeper简介

https://baijiahao.baidu.com/s?id=1594438991585121454&wfr=spider&for=pc
https://www.cnblogs.com/halu126/p/7078637.html
http://www.cnblogs.com/sunddenly/p/4138580.html
https://www.cnblogs.com/felixzh/p/5869212.html