The Edit Cluster page in ColdFusion Administrator lets you define the server instances for a cluster and to customize cluster settings. For more information on sticky sessions and clustering algorithm, see the JRun 4 documentation.
Add and remove JRun server instances by clicking the server name and the Left or Right Arrow button in the Modify Servers in Cluster area. To add or remove all JRun server instances, use the Double Arrow buttons.
When you finish configuring the servers in the cluster, click Submit.
(Optional) Specify a cluster algorithm.
Round robin (default): The web server connector sends each request to the next JRun server in the list.
Weighted round robin: The web server connector sends relatively more requests (one after the other) to certain JRun servers, as specified in the serverweight attribute.
Random weighted: The web server connector sends relatively more requests (in a random order) to JRun servers, as specified in the serverweight attribute.
Enable or disable sticky sessions, as follows:
Yes: The web server connector detects whether a request has an existing session and automatically routes that request to the original JRun server instance. If your ColdFusion application uses session management but does not use session replication, you must enable sticky sessions.
No: The web server connector routes incoming request to the next JRun server instance, as determined by the cluster algorithm.
Enable or disable session replication, as follows:
Yes: JRun automatically replicates session in-memory to other servers in the cluster.
No: Session replication is disabled. If your ColdFusion application uses session replication, sticky sessions are not typically required.
Note: When session replication is enabled, JRun propagates session-variable information to all servers in the cluster every time a session variable changes. Consider whether the application's business requirements require session replication and whether your network incur the increased traffic before enabling session replication. You might consider using client variables instead of session variables.
Click Submit.
Restart the server instances.
The sticky sessions and session replication options require the use
of J2EE Sessions by all instances participating in the cluster. To enable
J2EE sessions, go to the Memory Variables page
and enable the Use J2EE session variables option. You must do this for
each server in the cluster.
Note: Do not add the JRun admin server to a cluster. Additionally, the multiserver configuration prevents you from adding the localhost cfusion server to a cluster. (Although you can add a remote cfusion server to a cluster, this is not recommended.)