To use client-server clustering, deploy and start the Apache Ignite servers before you deploy and start Pega Platform. The Apache Ignite servers provide base clustering capabilities, including communication between nodes. You must have a minimum of three stand-alone Apache Ignite servers for one cluster.
Make sure that the JAVA_HOME environment variable points to a valid Java installation directory (JRE or JDK).
Move the prcluster_service.war file, which is used to start the cluster service, to the webapps directory of your Pega Platform distribution image. The file is in the Archives directory.
Configure the clustering protocol as Apache Ignite for all server nodes by using one of the following methods. The Hazelcast cluster protocol is the default configuration.
Create a Dynamic System Setting, which is the recommended approach for configuring the cluster protocol. Dynamic System Settings are used to set preferences on all nodes at once, but you have to restart each node for the setting to take effect.
For more details, see Creating a Dynamic System Setting or the PDN article How to compose the key of a PRCONFIG dynamic system setting. To define the Dynamic System Setting, enter the following values:
Pega-Engine in the Owning Ruleset field.
prconfig/identification/cluster/protocol/default in the Setting purpose field.
ignite in the Value field.
Edit the prconfig.xml file that is used by the servers.
Extract the content of the prcluster_service.war file in the webapps directory.
Add the following setting to the prconfig.xml file, which is in the webapps/prcluster_service/WEB-INF/classes/ directory:
<env name="identification/cluster/protocol" value="ignite" />
Pass the following JVM argument to the application server:
-DNodeSettings=identification/cluster/protocol=ignite
Configure your application server. For more information, see Configuring the application server in the appropriate deployment guide for your system.
Start your application server. The cluster service starts automatically.
After a successful startup, you can review the topology snapshot in the PegaRULES log files. By default, the log files are generated in the ../work/Catalina/localhost/prcluster_service/ directory and are accessible only from a terminal window.
Optional: Set up ELK (Elasticsearch, Logstash, and Kibana) for a convenient way to access and analyze the log files. For more information about configuring ELK, see the Configuring Elasticsearch, Logstash, and Kibana (ELK) for log management article on the PDN.