Here is a tutorial on how to use NiFi 1.0.0's zero-master clustering that uses Zookeeper so that there is never an issue of a cluster dying because of one master node going down.
Want to learn how to build an application with service discovery and client-side load balancing? Check out this post to learn more about using Eureka and Ribbon.
Look at containerizing a Spring Data Cassandra Application. More specifically, how to put a Spring application that connects to a Cassandra database into containers.