Add a Node to the Domain Orchestrator › Prerequisites to Installing a Cluster Node for the Domain Orchestrator

Prerequisites to Installing a Cluster Node for the Domain Orchestrator

You can install a cluster node for the Domain Orchestrator. A cluster node extends the processing power of the Domain Orchestrator and therefore can improve performance. A cluster node shares the same databases that were configured for the other existing nodes which are a part of the Domain Orchestrator cluster.

Before you install, perform the following prerequisites:

Follow these steps:

1. Identify a host for the Orchestrator cluster node that meets platform and hardware requirements. See the Orchestrator component in the following two topics:
   • Platform Support and Requirements for CA Process Automation Components.
   • Hardware Requirements.
2. Verify that the host for this cluster node is in the same subnet as other existing nodes which are a part of the Domain Orchestrator.
3. Verify that the host for this cluster node is in the same timezone as other existing nodes which are a part of the Domain Orchestrator.
4. Verify that the host for this cluster node has a supported JDK, and if missing, download it.

   See JDK Prerequisites.

5. If the host for this cluster node is running a recent version of a Windows operating system, review the User Account Control option (in the Control Panel, User Accounts). If this option is turned on, clear the check box and reboot this server.
6. If the Domain Orchestrator was configured with an F5 load balancer, add this node to the load balancer.

   See Create an F5 Node for Each Cluster Node.

7. If the Domain Orchestrator was configured with an Apache load balancer, add this node to the load balancer.
   1. Navigate to apache_install_location\conf.
   2. Open the workers.properties file.
   3. Uncomment the following lines under Define Node 2 in worker.properties file.

      worker.node2.port=8009
      

      worker.node2.host=hostname
      

      worker.node2.type=ajp13
      

      worker.node2.lbfactor=1
      

   4. Change hostname to the host name of the server where the Domain Orchestrator node is being installed.
   5. Add “node2” to the worker.loadbalancer.balance_workers= line under Load-balancing behavior. The entry resembles the following information:

      worker.loadbalancer.balance_workers=node1,node2
      

      Note: For third and subsequent nodes, follow the same instructions, but substitute the correct node number for node2, for example, node3 or node4.

   6. Restart Apache.
8. If the first node of the Domain Orchestrator was configured with an NGINX load balancer, add this node (node2) to the load balancer.
   1. Navigate to and open the pam-server.conf file.
   2. Find the #Define node2 line. (The node1 data refers to the first Domain Orchestrator node; skip sections that refer to node1)

      Note: The node2_hostname is the IP address or DNS name of the host where the node2 is installed. The jetty_server_port is the “Server Port” value supplied during installation of the first node of the Domain Orchestrator. Enter 80 for simplified communication or enter 7003 for deprecated communication.

   3. Create the following entries in pam-server.conf to define both node1 and the new node, node2:

      // node1 is the worker node name
      upstream node1{
        # Define node1
        server node2_hostname:jetty_server_port max_fails=3 fail_timeout=3s;
      }              
      // node2 is the worker node name
      upstream node2{
        # Define node2
        server node2_hostname:jetty_server_port max_fails=3 fail_timeout=3s;
      }      
      

   4. Inside server tag create following entries for both node1 and the new node, node2:

      Server{
      
      ...
          location = /ws {
                     // node1 is the upstream name provided above               
                     proxy_pass http://node1;                           
                     }  
          location = /ws/ {
                     // node1 is the upstream name provided above               
                     proxy_pass http://node1;                           
                     } 
          location = /ws/node1 {
                     // node1 is the upstream name provided above               
                     proxy_pass http://node1;                                                           
                     }  
          location /ws/node1/ {
                     // node1 is the upstream name provided above               
                     proxy_pass http://node1;                                           
                     } 
          location = /ws/node2 {
                     // node2 is the upstream name provided above  
      		   proxy_pass http://node2;                                                      
                     }  
          location /ws/node2/ {
                     // node2 is the upstream name provided above               
                     proxy_pass http://node2;                                           
                     }
      }