Chapter 4. Decision Server clusters in a runtime environment

Procedure

1. Install Red Hat JBoss EAP 7.1 on each node of the cluster:

   1. Navigate to the Software Downloads page in the Red Hat Customer Portal (login required) and select the product and version from the drop-down options:

      • Product: Enterprise Application Platform
      • Version: 7.1
   2. Click Download next to Red Hat JBoss Enterprise Application Platform 7.1.0. (jboss-eap-7.1.0.zip).
   3. Extract the jboss-eap-7.1.0.zip file. The jboss-eap-7.1/jboss-eap-7.1 directory is referred to as EAP_HOME.

2. Download and extract Decision Server:

   1. Navigate to the Software Downloads page in the Red Hat Customer Portal and select the product and version from the drop-down options:

      • Product: Decision Manager
      • Version: 7.1
      • Download Red Hat Decision Manager 7.1.0 Decision Server for All Supported EE7 Containers (rhdm-7.1.0-kie-server-ee7.zip).
   2. Extract the rhdm-7.1.0-kie-server-ee7.zip archive to a temporary directory. In the following examples this directory is called TEMP_DIR.

3. Repackage the kie-server.war directory:

   1. Navigate to the TEMP_DIR/rhdm-7.1.0-kie-server-ee7/kie-server.war directory.
   2. Select the contents of the TEMP_DIR/rhdm-7.1.0-kie-server-ee7/kie-server.war directory and create the kie-server.zip file.
   3. Rename kie-server.zip to kie-server.war. This is the file that you will use to deploy Decision Server on the cluster nodes.
   4. If desired, copy the new kie-server.war file to a location that is more convenient to deploy from.
4. If you want to use a security manager with Decision Server, copy the contents of the TEMP_DIR/rhdm-7.1.0-kie-server-ee7/SecurityPolicy directory to the EAP_HOME/bin directory on each node of the cluster.

Procedure

1. On the the master node of the cluster (where you will run the domain controller), open the EAP_HOME/domain/configuration/domain.xml file in a text editor.

2. Make the following changes for each server group in the server-groups element:

   1. Specify the server-group name and jvm name.

   2. To enable high availability, change the profile to full-ha and the socket-binding-group to full-ha-sockets.

      <server-group name="some-server-group" profile="full-ha">
          <jvm name="some-jvm">
              <heap size="1000m" max-size="1000m"/>
          </jvm>
          <socket-binding-group ref="full-ha-sockets"/>
      </server-group>

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3. In the <subsystem xmlns="urn:jboss:domain:messaging-activemq:2.0"> element, make the following changes:

   1. Replace <cluster password="${jboss.messaging.cluster.password:CHANGE ME!!}"/> with <cluster user="<CLUSTER_USER>" password="<CLUSTER_PWD>"/> where <CLUSTER_USER> is the user used by Red Hat JBoss EAP to form a messaging cluster and <CLUSTER_PWD> is the password for that user.

   2. In the security-setting element add the kie-server role:

      <subsystem xmlns="urn:jboss:domain:messaging-activemq:2.0">
          <server name="default">
              <security-setting name="#">
                  <role name="guest" send="true" consume="true" create-non-durable-queue="true" delete-non-durable-queue="true"/>
                  <role name="kie-server" send="true" consume="true" create-non-durable-queue="true" delete-non-durable-queue="true"/>
              </security-setting>

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4. Save the domain.xml file.

Procedure

1. Complete the following steps on the master node of the cluster:

   1. Open the EAP_HOME/domain/configuration/host.xml file in a text editor.
   2. In the main-server-group <servers> element, add the servers that will be part of the cluster.

2. Complete the following steps in the host.xml file on the master node and in the host-slave.xml file on each slave node:

   1. Open the EAP_HOME/domain/configuration/host-slave.xml file in a text editor.
   2. In the main-server-group <servers> element, add the servers that will be part of the cluster.

Procedure

1. Add Red Hat JBoss EAP management users to the master node (where you configured the domain.xml file) as described in the Red Hat JBoss EAP 7.1 Configuration Guide.

2. On each node of the cluster, add Decision Server users as described in Installing and configuring Red Hat Decision Manager on Red Hat JBoss EAP 7.1.

   1. To start the master node, enter one of the following commands:

      • On Linux or UNIX-based systems, enter:

        <EAP_HOME>/bin/domain.sh

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        On Windows, enter:

        <EAP_HOME>/bin/domain.bat

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   2. To start the slave nodes, on each of the slave nodes enter one of the following commands, where <MASTER_NODE_IP> is the IP address of the master node (where the domain controller is configured):

      • On Linux or UNIX-based systems, enter:

        <EAP_HOME>/bin/domain.sh --host-config=host-slave.xml -Djboss.domain.master.address=<MASTER_NODE_IP>

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      • On Windows, enter:

        <EAP_HOME>/bin/domain.bat --host-config=host-slave.xml -Djboss.domain.master.address=<MASTER_NODE_IP>

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        For more information, see the following sections of the Red Hat JBoss EAP 7.1 Configuration Guide:

      • "Starting JBoss EAP"
      • "Managed Domain Configuration Files".
3. On each node of the cluster, review the EAP_HOME/domain/servers/SERVER_NAME/log/server.log file to verify that the nodes are available.

4. To deploy the kie-server.war file that you created previously into the server group, complete the following steps on the master node:

   1. Log in to the Red Hat JBoss EAP Administration console of your domain as a management user.
   2. Click Deployments Server Groups→ main-server-group and click Add.
   3. In the dialog box, click Upload a new deployment and click Next.
   4. In the Upload Deployments dialog box, click Browse, select the kie-server.war file, and click Next.

   5. Click Enable and click Next.

      Note

      Make sure to check deployment unit readiness with every cluster member.

      When a deployment unit is created on a cluster node, it takes some time before it is distributed among all cluster members. You can check the deployment status using the server Administration console or REST API. However, if the query is sent to the node where the deployment was originally issued, the query will return a value of deployed. If the query is sent to a node where the deployment has not yet been distributed, the query returns DeploymentNotFoundException.

5. To verify that the Decision Server main endpoint is available and business process management (BPM) capabilities are enabled, enter the following command and replace <node_IP> and <node_port> with the IP address and port number of the node you are verifying:

   curl -X GET "http://<node_IP>:<node_port>/kie-server/services/rest/server"

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   If the following line is present in the output, BPM capabilities are enabled:

   <capabilities>BPM</capabilities>

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Procedure

1. Navigate to the Software Downloads page in the Red Hat Customer Portal (login required), and select the product and version from the drop-down options:

   • Product: Decision Manager
   • Version: 7.1
2. Download Red Hat Decision Manager 7.1.0 Add Ons (the rhdm-7.1.0-add-ons.zip file).
3. Unzip the rhdm-7.1.0-add-ons.zip file. The rhdm-7.1-controller-ee7.zip file is in the unzipped directory.
4. Extract the rhdm-7.1-controller-ee7.zip file to a temporary directory. In the following examples this directory is called TEMP_DIR.

5. Repackage the controller.war directory:

   1. Navigate to the TEMP_DIR/rhdm-7.1.0-add-ons/rhdm-7.1-controller-ee7/controller.war directory.
   2. Select the contents of the TEMP_DIR/rhdm-7.1.0-add-ons/rhdm-7.1-controller-ee7/controller.war directory and create the controller.zip file.
   3. Rename controller.zip to controller.war. This is the file that you will use to deploy the headless Decision Manager controller on the cluster nodes.
   4. If desired, copy the new controller.war file to a location that is more convenient to deploy from.
6. If you want to use a security manager with the headless Decision Manager controller, copy the contents of the TEMP_DIR/rhdm-7.1.0-add-ons/rhdm-7.1-controller-ee7/SecurityPolicy directory to the EAP_HOME/bin directory on each node of the cluster.
7. Add Red Hat JBoss EAP management users to the master node (where you configured the domain.xml file) as described in the Red Hat JBoss EAP 7.1 Configuration Guide.
8. On each node of the cluster, add users for the headless Decision Manager controller as described in the "Installing the headless Decision Manager controller" section of Installing and configuring Red Hat Decision Manager on Red Hat JBoss EAP 7.1.

9. Complete the following steps in the host.xml file on the master node and in the host-slave.xml file on each slave node:

   1. Open the EAP_HOME/domain/configuration/host.xml or EAP_HOME/domain/configuration/host-slave.xml file in a text editor.
   2. In the main-server-group <servers> element, add the servers that will be part of the cluster.

   3. Add the following properties to the <system-properties> element and replace <NFS_STORAGE> with the absolute path to the NFS storage where the template configuration is stored.

      <system-properties>
        <property name="org.kie.server.controller.templatefile.watcher.enabled" value="true"/>
        <property name="org.kie.server.controller.templatefile" value="<NFS_STORAGE>"/>
      </system-properties>

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      If the value of the org.kie.server.controller.templatefile.watcher.enabled property is set to true, a separate thread is started to watch for modifications of the template file. The default interval for these checks is 30000 milliseconds and can be further controlled by the org.kie.server.controller.templatefile.watcher.interval system property. If the value of this property is set to false, changes to the template file are detected only when the server restarts.

10. To deploy the controller.war file that you created previously into the server group, complete the following steps on the master node:

    1. Log in to the Red Hat JBoss EAP Administration console of your domain as a management user.
    2. Click Deployments Server Groups→ main-server-group and click Add.
    3. In the dialog box, click Upload a new deployment and click Next.
    4. In the Upload Deployments dialog box, click Browse, select the controller.war file, and click Next.

    5. Click Enable and click Next.

       Note

       Make sure to check deployment unit readiness with every cluster member.

       When a deployment unit is created on a cluster node, it takes some time before it is distributed among all cluster members. You can check the deployment status using the server Administration console or REST API. However, if the query is sent to the node where the deployment was originally issued, the query will return a value of deployed. If the query is sent to a node where the deployment has not yet been distributed, the query returns DeploymentNotFoundException.