Planning the configuration of a server farm
To plan the configuration of a server farm, choose the application server, write the configuration file, and deploy the WAR files.
When you intend to plan a server farm installation, you should first see Planning deployment of administration components and runtimes, and in particular see Server farm topology.
In IBM MobileFirst™ Platform Foundation, a server farm is composed of multiple stand-alone application servers that are not federated or administered by a managing component of an application server. MobileFirst Server internally provides a farm plug-in as the means to enhance an application server so that it can be part of a server farm.
When to declare a server farm
- Declare a server farm in the following cases:
- MobileFirst Server is installed on multiple Tomcat application servers.
- MobileFirst Server is installed on multiple WebSphere Application Server servers but not on WebSphere Application Server Network Deployer.
- MobileFirst Server is installed on multiple WebSphere Application Server Liberty servers.
- Do not declare a server farm in the following cases:
- Your application server is stand-alone.
- Multiple application servers are federated by WebSphere Application Server Network Deployment.
Why it is mandatory to declare a farm
Each time a management operation is performed through the MobileFirst Operations Console or through the MobileFirst Administration Services application, the operation needs to be replicated to all instances of a runtime environment. Examples of such management operations are the uploading of a new version of a wlapp or of an adapter. The replication is done via JMX calls performed by the MobileFirst Administration Services application instance that handles the operation. The Administration Service needs to contact all runtime instances in the cluster. In environments listed under When to declare a server farm, the runtime can be contacted through JMX only if a farm is configured. If a server is added to a cluster without proper configuration of the farm, the runtime in that server will be in an inconsistent state after each management operation, and until it is restarted again.