16.5. Configure a load-balanced cluster with NSAPI

Task: Configure a Load-balanced Cluster with NSAPI

Complete this task to configure a load-balanced cluster consisting of two worker nodes.

Prerequisites

  1. Define the paths to serve via NSAPI

    Open SJWS/PROFILE/config/obj.conf and define paths that should be served through NSAPI at the end of the default Object definition, as shown:
    <Object name="default">
          [...]
       NameTrans fn="assign-name" from="/status" name="jknsapi"
       NameTrans fn="assign-name" from="/images(|/*)" name="jknsapi"
       NameTrans fn="assign-name" from="/css(|/*)" name="jknsapi"
       NameTrans fn="assign-name" from="/nc(|/*)" name="jknsapi"
       NameTrans fn="assign-name" from="/jmx-console(|/*)" name="jknsapi"
       NameTrans fn="assign-name" from="/jkmanager/*" name="jknsapi"
    </Object>
    You can map the path of any application deployed on your JBoss Enterprise Platform instance in this obj.conf file. In the example code, the /nc path is mapped to an application deployed under the name nc.
  2. Define the worker that serves each path

    Open SJWS/PROFILE/config/obj.conf and add the following jknsapi Object definition after the default Object definition.
    <Object name="jknsapi">
       ObjectType fn=force-type type=text/plain
       Service fn="jk_service" worker="status" path="/jkmanager(/*)"
       Service fn="jk_service" worker="router"
    </Object>
    This jknsapi Object defines the worker nodes used to serve each path that was assigned to name="jknsapi" in the default Object.
  3. Define the workers and their attributes

    Create SJWS/PROFILE/config/workers.properties.
    Define the list of worker nodes and each worker node's properties in this file:

    Note

    For an explanation of workers.properties directives, refer to Appendix A, Reference: workers.properties
    # The advanced router LB worker
    worker.list=router,status
    
    #First EAP server definition, port 8009 is standard port for AJP in EAP
    #
    #lbfactor defines how much the worker will be used. 
    #The higher the number, the more requests are served
    #lbfactor is useful when one machine is more powerful 
    #ping_mode=A – all possible probes will be used to determine that
    #connections are still working
    worker.worker01.port=8009
    worker.worker01.host=127.0.0.1
    worker.worker01.type=ajp13
    worker.worker01.ping_mode=A
    worker.worker01.socket_timeout=10
    worker.worker01.lbfactor=3
    
    #Second EAP server definition
    worker.worker02.port=8009
    worker.worker02.host=127.0.0.100
    worker.worker02.type=ajp13
    worker.worker02.ping_mode=A
    worker.worker02.socket_timeout=10
    worker.worker02.lbfactor=1
    
    # Define the LB worker
    worker.router.type=lb
    worker.router.balance_workers=worker01,worker02
    
    # Define the status worker
    worker.status.type=status
  4. Restart the server

    Once your Sun Java System Web Server instance is configured, restart it so that your changes take effect.
    For Sun Java System Web Server 6.1:
    SJWS/PROFILE/stop
    SJWS/PROFILE/start
    For Sun Java System Web Server 7.0:
    SJWS/PROFILE/bin/stopserv
    SJWS/PROFILE/bin/startserv