Using Hazelcast IMDG Enterprise for PCF

This topic describes how developers use Hazelcast IMDG Enterprise for Pivotal Cloud Foundry (PCF).

After your PCF operator installs the Hazelcast IMDG Enterprise for PCF tile, it automatically registers itself to the Marketplace.

Follow these steps to create an instance of the Hazelcast service based on an available plan and bind it to your app. The plans available to you are determined by your PCF operator. For more information about configuring plans, see Installing and Configuring Hazelcast IMDG Enterprise for PCF.

1. To check availability of Hazelcast IMDG Enterprise for PCF, enter the following command:

   $ cf marketplace
   

   For example,

   $ cf marketplace
   Getting services from marketplace in org system / space system as admin...
   OK
   
   service         plans                            description
   app-autoscaler  bronze, gold                     Scales bound applications in response to load (beta)
   hazelcast       t2.micro, t2.small, m3.medium    Hazelcast Service
   

2. Create a file named hazelcast.json using this sample Hazelcast JSON file as a template.

3. Replace YOUR_LICENSE_KEY with the active Hazelcast Enterprise License or a trial license. For more information, see License.

4. To create a cluster, enter the following command:

   $ cf create-service hazelcast PLAN SERVICE_INSTANCE_NAME -c hazelcast.json
   

   For example,

   $ cf create-service hazelcast t2.micro micro-cluster -c hazelcast.json
   Creating service instance micro-cluster in org system / space system as admin...
   OK
   
   Create in progress. Use 'cf services' or 'cf service micro-cluster' to check operation status.
   

5. To bind the service to your app, enter the following commands:

   $ cf bind-service MY-APPLICATION SERVICE_INSTANCE_NAME
   $ cf restage MY-APPLICATION
   

   For example,

   $ cf bind-service myapp micro-cluster
   $ cf restage myapp
   

6. Start using the Hazelcast in-memory data grid (IMDG). Necessary parameters are passed to your application in VCAP_SERVICES environment variable. See this sample Hazelcast Spring Boot application for further information.

Configuring WAN replication

This section explains a way to configure WAN replication in PCF. Please see the official documentation for reference.

Source cluster

In this example, we will use the Eureka service registry for target cluster discovery. This was tested with Eureka server version 1.4.12.

Edit the hazelcast.json file for the source cluster to include the following wanReplicationConfigs configuration:

  "wanReplicationConfigs": {
    "my-wan-cluster-batch": {
      "name": "my-wan-cluster-batch",
      "wanPublisherConfigs": [
        {
          "groupName": "cluster-name",
          "queueCapacity": 10000,
          "queueFullBehavior": "DISCARD_AFTER_MUTATION",
          "properties": {
            "maxEndpoints": 5,
            "group.password": "cluster-password",
            "batch.max.delay.millis": 1000
          },
          "className": "com.hazelcast.enterprise.wan.replication.WanBatchReplication",
          "awsConfig": {
            "enabled": false,
            "region": "us-east-1",
            "hostHeader": "ec2.amazonaws.com",
            "connectionTimeoutSeconds": 5
          },
          "discoveryConfig": {
            "discoveryStrategyConfigs": [
              {
                "properties": {
                  "environment": "test",
                  "shouldUseDns": false,
                  "serviceUrl.default": "http://<my-eureka>/eureka",
                  "namespace": "hazelcast",
                  "name": "hazelcast-target",
                  "use-classpath-eureka-client-props": false,
                  "self-registration": false
                },
                "className": "com.hazelcast.eureka.one.EurekaOneDiscoveryStrategy"
              }
            ]
          }
        }
      ]
    }
  }

Change groupName and group.password to match your existing target cluster configuration, serviceUrl.default to match your Eureka service endpoint, and any other config values to your needs.

In this example we want to set up WAN replication for a map called my-map. This can be achieved by including the following mapConfigs configuration in your hazelcast.json:

  "mapConfigs": {
    "my-map": {
      "name": "my-map",
      "backupCount": 1,
      "asyncBackupCount": 0,
      "timeToLiveSeconds": 0,
      "maxIdleSeconds": 0,
      "maxSizeConfig": {
        "maxSizePolicy": "PER_NODE",
        "size": 2147483647
      },
      "evictionPolicy": "NONE",
      "mapStoreConfig": {
        "enabled": false,
        "writeCoalescing": true,
        "writeDelaySeconds": 0,
        "writeBatchSize": 1,
        "properties": {},
        "initialLoadMode": "LAZY"
      },
      "readBackupData": false,
      "cacheDeserializedValues": "INDEX_ONLY",
      "mergePolicy": "com.hazelcast.map.merge.PutIfAbsentMapMergePolicy",
      "inMemoryFormat": "BINARY",
      "wanReplicationRef": {
        "name": "my-wan-cluster-batch",
        "mergePolicy": "com.hazelcast.map.merge.PassThroughMergePolicy",
        "filters": [],
        "republishingEnabled": false
      },
      "statisticsEnabled": true,
      "hotRestartConfig": {
        "enabled": false,
        "fsync": false
      }
    }
  }

Change any value as needed.

Management Center support

In order to enable the WAN replication features in Management Center (e.g., manual sync) don’t forget to include the following properties configuration:

  "properties": {
    "hazelcast.rest.enabled": true
  }

Target cluster

In this example, we will use the Eureka service registry for cluster member discovery. This allows the other cluster (the source cluster) to find the addresses for this cluster by means of Eureka, as shown in the previous example.

Edit the hazelcast.json file for the target cluster to include the following networkConfig configuration:

  "networkConfig": {
    "port": 5701,
    "portCount": 100,
    "portAutoIncrement": true,
    "reuseAddress": true,
    "interfaces": {
      "enabled": false,
      "interfaceSet": []
    },
    "join": {
      "multicastConfig": {
        "enabled": false,
        "multicastGroup": "224.2.2.3",
        "multicastPort": 54327,
        "multicastTimeoutSeconds": 2,
        "multicastTimeToLive": 32,
        "trustedInterfaces": [],
        "loopbackModeEnabled": false
      },
      "tcpIpConfig": {
        "connectionTimeoutSeconds": 5,
        "enabled": false,
        "members": []
      },
      "awsConfig": {
        "enabled": false,
        "region": "us-east-1",
        "hostHeader": "ec2.amazonaws.com",
        "connectionTimeoutSeconds": 5
      },
      "discoveryConfig": {
        "discoveryStrategyConfigs": [
          {
            "properties": {
              "environment": "test",
              "shouldUseDns": false,
              "serviceUrl.default": "http://<my-eureka>/eureka",
              "namespace": "hazelcast",
              "name": "hazelcast-target",
              "use-classpath-eureka-client-props": false
            },
            "className": "com.hazelcast.eureka.one.EurekaOneDiscoveryStrategy"
          }
        ]
      }
    }

Change serviceUrl.default to match your Eureka service endpoint, and any other config values to your needs.