One of the best features of Akka is Akka Cluster. Akka cluster allows for building distributed applications, where one application or service spans multiple nodes. From its initial release in 2013, Akka Cluster needed a node management system to manage the Akka nodes and to provide a resilient and elastic platform. With Kubernetes Akka finally has the node management system that is has been waiting for. Akka Cluster has been designed to gracefully handle nodes leaving and joining a running cluster while continuing to run. Kubernetes adds and removes nodes as needed to increase capacity or to recover from failures. In effect, there is a perfect symbiosis between Akka Cluster and Kubernetes. In this talk, we will look at and demonstrate how Akka Java Cluster and Kubernetes work together and how together they form a beautiful relationship.

1. Hugh McKee (@mckeeh3), Developer Advocate
Akka and Kubernetes:
The beginning of a beautiful relationship

2. Akka cluster and OpenShift
Live demo

3. “Crop Circle”
Shows
Running Pods / JVMs

4. “Crop Circle”
Shows
Running Pods / JVMs
POD / JVM
POD / JVM
POD / JVM

5. Entity
Shard
Singleton
HTTP Server
Pod

6. Entities added as needed
Inactive entities shutdown

7. The enabler of these characteristics is a Cloud-Ready Message Driven Model.
Lightbend codified these principles into the Reactive Manifesto in 2013; 24,000+ signatories around the world so far.
Responsive Resilient Elastic
React to
Users
React to
Failures
React to
Load Variance
Low latency / High
performance
Real-time / NRT
Graceful, Non-catastrophic
Recovery
Self-Healing
Responsive in the face of
changing loads
Reactive Systems

8. Clustered Entity Actors

9. You
entity 64
Load Balancer
Me
entity 17
Other
entity 76

10. You
entity 64
Load Balancer
Me
entity 17
Other
entity 76

11. Load Balancer
Server 1

12. Load Balancer
Server 2Server 1 Server 3

13. Load Balancer
Server 2Server 1 Server 3

14. User ID Time Event
You 64 08:11 Add Item 1567
Me 17 08:15 Add Item 3254
Other 76 08:16 Add Item 8359
You 64 08:20 Add Item 2632
Me 17 08:20 Add Item 4983
Other 76 08:24 Change Item 8359
You 64 08:25 Remove Item 1567
You 64 08:26 Add shipping address
Other 76 08:30 Add Item 2438
Me 17 08:33 Add shipping address
Me 17 08:33 Add billing address
You 64 08:35 Add billing address

16. Distributed Actors
Cluster Aware
Actors

17. Distributed Actors
Cluster Aware
Actors

18. Distributed Actors
Cluster Aware
Actors

19. Distributed Actors
Cluster Aware
Actors

20. Distributed Actors
Cluster Aware
Actors

21. Distributed Actors
Cluster Aware
Actors

22. Shard Distribution
Akka Cluster Singleton

23. Shard Distribution
Akka Cluster Singleton

24. Shard Distribution
Akka Cluster Singleton

25. Entity Distributed Sharding
Akka Cluster Sharding

26. Entity Distributed
Sharding
Akka Cluster Sharding

27. Event Sourcing & CQRS
Akka Persistence & Persistence Query

28. Event Sourcing & CQRS
Akka Persistence &
Persistence Query

29. Akka Reactive Systems and OpenShift
Responsive Resilient Elastic
React to
Users
React to
Failures
React to
Load Variance
Low latency / High
performance
Real-time / NRT
Graceful, Non-catastrophic
Recovery
Self-Healing
Responsive in the face of
changing loads
a beautiful relationship

30. /akka-java-cluster-ibm-cloud
/akka-java-cluster.git
/akka-java-cluster-aware.git
/akka-java-cluster-singleton.git
/akka-java-cluster-sharding.git
/akka-java-cluster-persistence.git
/akka-java-cluster-persistence-query.git
https://github.com/mckeeh3…

31. Upgrade your grey matter!
Get the free O’Reilly book by Hugh McKee,
Developer Advocate at Lightbend
https://www.lightbend.com/resources/e-books

32. Hugh McKee (@mckeeh3), Developer Advocate
hugh.mckee@lightbend.com
Akka and Kubernetes:
The beginning of a beautiful relationship