With the introduction of connection based load balancing, cluster communications can no longer be over 1-way SSL. Currently, the client auth property of nifi.properties only applied to these cluster communications. If set to false, a cluster will fail with the following exception:
This property is not used currently for site-to-site which requires it to be `required` (which is the proposed solution here).
This property is not used currently for Jetty which will `require` or `want` it based on the configured features.