New Features › CA Process Automation Release 04.2.00 › Communication Improvements

Communication Improvements

The following summary focuses on communication improvements.

• Simplified agent communication.
  • Formerly, connections between Orchestrators and Agents were initiated bi-directionally using non-standard internet ports (7001, 7003, 8080, 8443). This was problematic for agents residing behind firewalls, proxies, and NAT routers. This style of communication is referred to as deprecated communication. Simplified communication was not available.
  • The new simplified communication initiates connections from the agent to the Orchestrator using only standard internet ports (80, 443). An Orchestrator sends messages to an agent using a persistent websocket connection. This connection is established from the agent using standard internet ports.

    Note: You can configure existing agents to change from deprecated communication (default) to simplified communication. See the Content Administrator Guide for agent configuration details. Configure a load balancer that supports web socket connections. See the Installation Guide for details.

• NGINX load balancer support
  • Formerly, Apache was the recommended software load balancer used for clustered Orchestrators. However, Apache does not support simplified agent communication.
  • Now, CA Technologies recommends NGINX as a software load balancer that supports simplified communication. For caveats, see the next section, New Recommendations for Load Balancers. The installation media includes a sample configuration file for this load balancer. See the Installation Guide for information about setting up NGINX.

    Note: Optionally, you can use another load balancer that supports persistent web socket connections.

• New Recommendation for Load Balancers

  The following recommendations for CA Process Automation 4.2 are listed in order of preference:

  • (Preferred) Use a hardware load balancer, for example, use F5.
  • Use a software load balancer on Linux, for example, NGINX.
  • If you must run a software load balancer on Windows, use NGINX, but be aware that the number of agents that can be operated using the simplified communication is limited to approximately 300.
• Changes to Apache Templates - You must update your Apache configuration with the updated templates supplied on the installation media as a prerequisite to upgrade.

  Note: After you have upgraded CA Process Automation and verified that everything is working as expected, you can install and configure NGINX and switch load balancers. Reconfigured and restarted agents can then use simplified communication.

• Changes to F5 Updated F5 iRule Definition.
  • Previously there was one pool PAMSRVR with either 8080 (unsecure) or 8443 (secure) for the port.
  • Now there is an additional pool (PAMJETTYPOOL) that supports simplified communication with either 80 or 443 for the port. If upgrading, you add the new pool; if setting up F5 for the first time you create two pools and add members with different ports.
• Changes to F5 when configuring secure communication
  • Previously, you could use a self-signed certificate and a key file to enable SSL communication.
  • To use the new r4.2 simplified communication, you must upload SSL certificate file from the CA Process Automation keystore and create client and server profiles that link these certificates.