Planning for network ports

WebSphere® eXtreme Scale is a distributed cache that requires opening ports to communicate with the Object Request Broker (ORB) and Transmission Control Protocol (TCP) stack among Java™ Virtual Machines and other machines. You should plan and control your ports, especially in a firewall environment such as when you are using a catalog service and containers on multiple ports.

Catalog service grid

A catalog service grid requires the following.
  1. peerPort for the high-availability (HA) manager to communicate between peer catalog servers over a TCP stack
  2. clientPort for catalog servers to access catalog service data
  3. JMXServicePort to specify which port the JMX service should use
  4. ORB listener port for containers and clients to communicate with the catalog service through the ORB
Use the startOgServer command to specify the ports previously listed with the option in stand-alone, as shown in the following example:
 –catalogServiceEndPoints cs1:host1:clientPort:peerPort, cs2:host2:clientPort:peerPort, 
cs3:host3:clientPort:peerPort -listenerPort <orbPort> -JMXServicePort <jmxPort>
In a WebSphere Application Server environment, the ports in the previous list are specified in WebSphere cell custom properties with key catalog.services.cluster as:
  • cell\node1\server1:host1:clientPort:peerPort:listenerPort
  • cell\node2\server2:host2:clientPort:peerPort:listenerPort
The WebSphere eXtreme Scale container servers also require several ports to operate. By default, the eXtreme Scale container server generates its HA manager port and ORB listener port automatically with dynamic ports. In the firewall environment, since it is advantageous for you to plan and control ports, options are provided to start eXtreme Scale container servers with specified HAManager port and ORB listener port with an option in the startOgServer command, as shown in the following example:
-HaManagerPort <peerPort>
-listenerPort <orbPort>

Proper planning of port control is a benefit, but there is an inherent difficulty to plan and manage these ports when hundreds of Java Virtual Machines are started in a machine. Any port conflict will cause a failure of server startup.

When security is enabled, a Secure Socket Layer (SSL) port is a required addition to the ports listed previously. Using Dcom.ibm.CSI.SSLPort=<sslPort> as a -jvmArgs argument sets the SSL port to <sslPort>. Read more about security settings for eXtreme Scale to assist in planning for ports.