https://issues.apache.org/jira/browse/FLINK-10030
https://issues.apache.org/jira/browse/FLINK-10011
https://github.com/apache/flink/pull/6590/commits/762ee1ff299e4ee9da3af2ff030c049ebbbc07b3
https://github.com/apache/flink/pull/6590/commits/42495537888370c8c7d84abbdd1256a7256477d3
http://apache-flink-mailing-list-archive.1008284.n3.nabble.com/Zookeeper-failure-handling-td19611.html
https://github.com/apache/flink/pull/3599