Running

Running from IDE

A worker node

Set the following Java Virtual Machine properties which are handled by akka

• instance port in cluster:

  -Dakka.remote.artery.canonical.port=10001

  By default, 25520 port number is used.

• instance hostname:

  -Dakka.remote.artery.canonical.hostname=127.0.0.1.

  Otherwise, Akka Cluster will autodetect an IP address.

• reference to any running cluster node -- seed node.

  By default, we will refer to the primary cluster node represented by the first worker node. Note that even a single-node cluster requires a seed node.

  -Dakka.cluster.seed-nodes.0=akka://system@127.0.0.1:10001.

Second and third worker node

Second and third worker node require a specific ports, such as 10002, 10003. They will refer to the same seed node.

Running via Gradle

Run a single node:

./gradlew run -P=akkaHost=127.0.0.1 -PakkaPort=10001 -PakkaSeedNode=127.0.0.1:10001 -PakkaRole=guardian

Run a worker node:

./gradlew run -P=akkaHost=127.0.0.1 -PakkaPort=10002 -PakkaSeedNode=127.0.0.1:10001 -PakkaRole=worker

Run a secondary worker node:

./gradlew run -P=akkaHost=127.0.0.1 -PakkaPort=10003 -PakkaSeedNode=127.0.0.1:10001 -PakkaRole=worker

Architecture

The Runner runs in one of two roles.

• worker mode: creates a new actor system with a single Worker actor. This will launch a single actor per application instance. Each Worker registers itself in the global Akka Receptionist under a specific service key.
• guardian mode: creates a new actor system containing a single group router. Such a router will autodetect all Worker actors with the specific service key. All messages sent to the actor system will be routed to all Worker nodes, essentially creating a distributed system.

Future Work

• We can distinguish between two modes in a specific actor, which will discover the cluster node role and spawn a specific set of actors.
• We can create a single-node worker pool, where a pool router will handle incoming messages and route to the Worker actors. Then, we can create both concurrent and distributed system with a common underlying philosphy.