A newer version of IMDG is available.

View latest

Want to try Hazelcast 5.0 beta?

We’ve combined the in-memory storage of IMDG with the stream processing power of Jet to bring you an all new Hazelcast platform.

Discovering Native Clients

Hazelcast members and native Java clients can find each other with multicast discovery plugin. This plugin is implemented using Hazelcast Discovery SPI. You should configure the plugin both at Hazelcast members and Java clients in order to use multicast discovery.

To configure your cluster to have the multicast discovery plugin, follow these steps:

  • Disable the multicast and TCP/IP join mechanisms. To do this, set the enabled attributes of the multicast and tcp-ip elements to false in your hazelcast.xml configuration file

  • Set the enabled attribute of the hazelcast.discovery.enabled property to true.

  • Add multicast discovery strategy configuration to your XML file, i.e., <discovery-strategies> element.

The following is an example declarative configuration.

<hazelcast>
    ...
    <properties>
        <property name="hazelcast.discovery.enabled">true</property>
    </properties>
    <network>
        <join>
            <multicast enabled="false">
            </multicast>
            <tcp-ip enabled="false">
            </tcp-ip>
            <discovery-strategies>
                <discovery-strategy class="com.hazelcast.spi.discovery.multicast.MulticastDiscoveryStrategy" enabled="true">
                    <properties>
                        <property name="group">224.2.2.3</property>
                        <property name="port">54327</property>
                    </properties>
                </discovery-strategy>
            </discovery-strategies>
        </join>
    </network>
    ...
</hazelcast>

The following are the multicast discovery plugin configuration properties with their descriptions:

  • group: String value that is used to set the multicast group, so that you can isolate your clusters.

  • port: Integer value that is used to set the multicast port.