A weight advisor collects information that advises each cluster member as to what its weight should be dynamically (during run time). A weight can be set by a weight advisor using the console, scripting, or the ClusterMgr MBean. To enable a weight advisor using the console, you specify WebSphere Dynamic Weighting when defining a weight advisor.
If the weight for a cluster member is set by a weight advisor, the dWLM Application takes the weight for the cluster member and passes the weight value back to the WLMServlet Advisor loaded in the Content Based Routing (CBR) component at the HTTP front end.
For information on the WLMServlet Advisor and the CBR component, refer to the Load Balancer Administration Guide . At that URL, click Load Balancer Administration Guide > Content Based Routing (CBR) component > Load balancing WebSphere Application Servers (WAS).
This article suggests how to fix problems that might arise.
Weights are not updated in the Load Balancer's WLMServlet Advisor
Problem | The virtual host is not defined in the virtual host list for cluster members. |
Recommended response | The dWLM Application for the cluster member is installed to the default
virtual host. Ensure that the virtual host entries for cluster members are
shown in the virtual host
list. If the cluster contains Web modules that have a custom virtual host list, you can specify that the dWLM Application use that virtual host list:
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dWLM Application is not installed
Problem | The name of the dWLM Application for the cluster is not shown on the Enterprise Applications page, which you access by clicking Applications > Enterprise Applications. |
Recommended response | Check the deployment manager logs for dWLM Application installation errors. The dWLM Application (wlmservlet.ear) is under the Deployment_Manager_installation_root\installableApps directory. If the logs do not mention dWLM Application errors, contact IBM support. |
Weights have not changed for the WLMServlet Advisor in the Load Balancer
Problem | The weights are updated only when they change. Even after updating, the weights have not changed. |
Recommended response | If the weights are changed through the console, refer to "Assigning weights to cluster members." If the weights are changed by the weight advisor, refer to "Backup clusters." If weights are updated through the ClusterMgr MBean, verify that these updates are reflected on the Runtime tab for the cluster member. |
dWLM Application installed without request to do so
Problem | The dWLM Application might install when another application installs, even though you do not want to use the dWLM Application or dynamic workload management. |
Recommended response | To stop installation of the dWLM Application, do one of the following:
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