Axon Server Clustering

NOTE: This feature is only available on the Enterprise Edition of AxonServer

When running Axon Server in a licensed edition, you can set up a cluster of Axon servers. The servers run in active/active mode, so each node can receive and handle requests.

You can set the following properties in the axonserver.properties configuration file:

• axoniq.axonserver.name - logical name of the node in the cluster. This must be unique within the cluster.

• axoniq.axonserver.hostname - sets the hostname as this node advertises it to clients

• axoniq.axonserver.domain - sets the domain as used in returning the server address to clients

• axoniq.axonserver.internal-hostname - hostname to be used by other nodes in the server cluster

• axoniq.axonserver.internal-domain - domain to be used by other nodes in the server cluster

• axoniq.axonserver.internal-port - internal gRPC port number for communication to other nodes

When there is no hostname specified it defaults to the hostname as returned by the hostname command.

Sample configuration:

axoniq.axonserver.hostname=messaging1.axoniq.io
axoniq.axonserver.name=messaging1

Connecting the nodes of a cluster is done using the command line interface. Send the register-node command to one node, specifying the address of another node in the cluster, e.g.

# java -jar axoniq-cli.jar register-node -S http://node-to-add:port -h node-in-cluster -p internal-port-of-node-in-cluster

When you have a default setup with all nodes using the default port you can omit a number of parameters from this request. To connect node2 to with node1 run the following command on node2:

# java -jar axoniq-cli.jar register-node -h node1

Default value for -S option is http://localhost:8024 and for -p is 8224 (default internal communication port).

This only has to be done once, each node maintains a list of all nodes in the cluster.

Internal APIs and stability guarantees

Within the endpoints documented in /swagger-ui.html, you can find some /internal/* APIs that are not part of the public APIs. These APIs are not supposed to be used and will change without notice.