Replicate a Map over Clusters in a WAN

Create a hazelcast.yaml (or XML) configuration file with the following content and place it in ~/config-tokyo directory.

hazelcast:
  cluster-name: tokyo
  license-key: <your license key>
  wan-replication:
    london-wan-rep:
      batch-publisher:
        londonPublisherId:
          cluster-name: london
          target-endpoints: <host_ip>:5701
  map:
    cities: (1)
      wan-replication-ref:
        london-wan-rep: (2)
          republishing-enabled: false

<hazelcast>
    <cluster-name>tokyo</cluster-name>
    <license-key>"your license key"</license-key>
    <wan-replication name="london-wan-rep">
        <batch-publisher>
            <cluster-name>london</cluster-name>
            <publisher-id>londonPublisherId</publisher-id>
            <target-endpoints>"host_ip":5701</target-endpoints>
    <map name="cities">
        <wan-replication-ref name="london-wan-rep">
    </map>
</hazelcast>

Open a new terminal and start the active cluster.

docker run \
     --network hazelcast-network \
     -e JAVA_OPTS="-Dhazelcast.config=/opt/hazelcast/config_ext/hazelcast.yaml" -v ~/config-tokyo:/opt/hazelcast/config_ext hazelcast/hazelcast-enterprise:5.2.5

Start Management Center

docker run \
    --network hazelcast-network \
    -p 8080:8080 hazelcast/management-center:5.2.5

Once you see the Hazelcast Management Center successfully started at http://localhost:8080/ log in the terminal, open a web browser, go to localhost:8080, and enable Dev Mode.

You will see a Connect box on the screen; click on it and enter the passive cluster’s name (london) and IP address of its member.

Click Connect again and enter the active cluster’s name (tokyo) and the IP address of its member.

You need to provide your license key; this is needed since you are going to use the WAN Replication feature for the tokyo cluster in Management Center. Click on View Cluster for tokyo, go to Settings located on the very top right of the user interface and, select License.

Verify that the tokyo cluster has WAN Replication enabled. Go to Cluster > WAN Replication.

In a new terminal, start the SQL shell that will be connected to the tokyo cluster.

docker run --network hazelcast-network -it --rm hazelcast/hazelcast:5.2.5 hz-cli --targets tokyo@172.18.0.4:5701 sql

Once you see the SQL shell (sql>), type the following command and press Enter to create the map.

CREATE MAPPING cities (__key INT, country VARCHAR, city VARCHAR)
TYPE IMap
OPTIONS ('keyFormat'='int', 'valueFormat' = 'json-flat');

Then, type the following command and press Enter to add data to the map.

INSERT INTO cities VALUES
(1,'Australia','Canberra'),
(2,'Croatia','Zagreb'),
(3,'Czech Republic','Prague'),
(4,'England','London'),
(5,'Turkey','Ankara'),
(6,'United States','Washington, DC');

See the entries by running the following query.

SELECT * FROM cities;

Select tokyo in the dropdown field left to Cluster Connections on top of the user interface.

Go to Storage > Maps, you will see the cities map information.

Click on SQL Browser located on the very top right of the user interface and choose cities in the select a map field. The SQL browser then shows the default query in its editor, SELECT * FROM cities;.

Click on Execute Query; you will see the data you’ve put in.

Close the SQL browser.

In Management Center, select london in the dropdown field left to Cluster Connections on top of the user interface.

Go to Storage > Maps and see that the cities map is there.

You first need to create the mapping so that the london cluster can read the map entries. Open the SQL browser, type in the following query.

CREATE MAPPING cities (__key INT, country VARCHAR, city VARCHAR)
TYPE IMap
OPTIONS ('keyFormat'='int', 'valueFormat' = 'json-flat');

Click Execute Query.

In the select a map field, choose cities. The editor shows the default SELECT * FROM cities; query. Once you execute it, you will see the entries of cities map, as in Step 4.

Close the SQL browser.

Select tokyo in the dropdown field left to Cluster Connections on top of the user interface and go to SQL Browser.

Choose cities in the select a map field and execute the default SELECT * FROM "cities" query.

Now, you are going to modify the data shown above in the red box (the entry having the key 1). In the SQL editor, delete the default query and type in the following command.

SINK INTO cities VALUES
(1, 'Austria', 'Vienna');

Close the SQL browser and now go to the passive cluster (london) by choosing london in the dropdown field left to Cluster Connections on top of the user interface.

Open the SQL browser, choose cities in the select a map field and execute the default query.

You will see the entry having the key 1 is also modified.