Is it possible to encrypt all communication from/to Zookeeper? I haven't seen any HDP documentation.
I have never tried the same on my local HDP setup but looks like Zookeeper can be configured to use SSL for encrypted communication.
By default network communication of ZooKeeper isn’t encrypted. However, each user and service can leverage the SSL feature and/or custom authentication implementation in order to use ZooKeeper in secure mode.This feature is added from Zookeeper version 3.5.1, 3.6.0 as part of "Sub Task" JIRA: https://issues.apache.org/jira/browse/ZOOKEEPER-2125
Unfortunately even the latest HDP version (which is HDP 2.6.3) includes the Zookeeper version "Apache ZooKeeper 3.4.6" so this feature is not available in HDP yet.