Resolution

In order to secure Tableau Server internal communications between nodes in a cluster, the cluster must be protected from external traffic using network security such as a firewall.

Tableau Server does not authenticate a new Zookeeper node when it joins a quorum, so Zookeeper ports need to be in the set of ports that are protected from external communication. The documents linked below address the hardening and configuration of those ports:

Tableau Server-Security Hardening:
https://help.tableau.com/current/server/en-us/security_harden.htm

Tableau Server-Ports:
https://help.tableau.com/current/server/en-us/ports.htm

Cause

Additional Information

For additional information on Zookeeper security, please see the link below.

Apache Zookeeper
https://zookeeper.apache.org/security.html