This guided activity leads you through a simple set of steps for creating a server cluster and making applications on the cluster highly available. See <a target="help" href="http://www14.software.ibm.com/webapp/wsbroker/redirect?version=phil&product=was-nd-dist&topic=trun_wlm_cluster">Creating Clusters</a> in the Information Center for more information about creating and configuring a cluster. See <a target="help" href="http://www14.software.ibm.com/webapp/wsbroker/redirect?version=phil&product=was-nd-dist&topic=trun_ha_environment ">Setting up a high availability environment</a> in the Information Center for more information about making applications highly available. To continue, click Start. A cluster is a set of application servers that are managed together and participate in workload management. See <a target="help" href="http://www14.software.ibm.com/webapp/wsbroker/redirect?version=phil&product=was-nd-dist&topic=welcclusters ">Introduction: Clusters</a> in the Information Center for more information about clusters. <A HREF="javascript:showHideList('custom1')"> <IMG SRC="/ibm/console/images/arrow_collapsed.gif" ALT="" ID="custom1Img" ALIGN="left" BORDER="0" style="margin-left:-0.25em"/> </A> To create a new cluster <TABLE id="custom1List" style="font-size:100%;margin-left:1em;display:none"> <TR> <TD> <ol> <li>Click Click to Perform to load the list of clusters</li> <li>Click New to launch the cluster creation wizard</li> </ol> </TD> </TR> </TABLE> Note: This guided activity uses basic memory-to-memory replication for HTTP sessions. Be sure to check the HTTP session memory-to-memory replication checkbox in the cluster creation wizard to automatically create a replication domain and add the cluster members to it. If you wish to persist sessions to a database instead, see <a target="help" href="http://www14.software.ibm.com/webapp/wsbroker/redirect?version=phil&product=was-nd-dist&topic=tpercnfp">Configuring for database session persistence</a> in the Information Center for more information. Use this section to install an application using the application installation wizard. Tip: On the step for Map modules to servers, the application is targeted by default to the first available server or cluster; be sure to check that the application is mapped to the correct cluster within that wizard step. Enabing stateful session bean failover is relevant to applications running in a clustered environment. Multiple stateful session beans may exist within an application or a module, some or all of which may be enabled for failover. Setting failover at the server, application, and module levels allows different levels of control of which beans are failover-enabled and which are not. For this guided activity, stateful session bean failover will be configured at the server level, which is the default. Note: Because enabling failover has performance and resource costs, you may consider overriding the server level settings by enabling failover at the module or application level, therefore providing failover for only the session beans in the selected application or module. See <a target="help" href="http://www14.software.ibm.com/webapp/wsbroker/redirect?version=phil&product=was-nd-dist&topic=cejb_sfsbf ">Stateful session bean failover for the EJB container</a> in the Information Center for more information on determining when to override the default. If you wish to configure stateful session bean failover and to persist HTTP sessions, both must use memory-to-memory replication. <A HREF="javascript:showHideList('custom3')"> <IMG SRC="/ibm/console/images/arrow_collapsed.gif" ALT="" ID="custom3Img" ALIGN="left" BORDER="0" style="margin-left:-0.25em"/> </A> Set stateful session bean failover at the server level <TABLE id="custom3List" style="font-size:100%;margin-left:1em;display:none"> <TR> <TD> <ol> <li>Click Click to Perform to load the list of clusters</li> <li>Click a cluster name to load the cluster detail.</li> <li>Click Cluster members under the Additional Properties to load the list of cluster members</li> <li>Click a cluster member name to load the cluster member detail.</li> <li>Click EJB Container under the EJB Container Settings section in Container Settings to load the EJB Container detail</li> <li>Click memory-to-memory replication</li> <li>In the Replication domain select list, select the domain that has the same name as the cluster created previously.</li> <li>Click OK to return to the EJB Container detail.</li> <li>Very that Enable stateful session bean failover using memory-to-memory replication is now checked.</li> <li>Repeat steps 4-9 for each cluster member</li> </ol> </TD> </TR> </TABLE> To continue, click Next step. In distributed platforms, assigning weights to cluster members allows you to balance the workload within the cluster. Weighting should be based upon hardware capacity and the number of running processes. See <a target="help" href="http://www14.software.ibm.com/webapp/wsbroker/redirect?version=phil&product=was-nd-dist&topic=crun_srvgrp ">Clusters and workload management</a> in the Information Center for more information about best practices. If the weight value for the server is greater than the weight values that are assigned to other servers in the cluster, the server receives a larger share of the cluster workload. The value can range from 0 to 20. Enter zero to indicate that you do not want requests to route to this application server unless this server is the only server that is available to receive requests. <A HREF="javascript:showHideList('custom6')"> <IMG SRC="/ibm/console/images/arrow_collapsed.gif" ALT="" ID="custom6Img" ALIGN="left" BORDER="0" style="margin-left:-0.25em"/> </A> To set member weights: <TABLE id="custom6List" style="font-size:100%;margin-left:1em;display:none"> <TR> <TD> <ol> <li>Click Click to Perform to load the list of clusters</li> <li>Select a cluster</li> <li>Select Cluster members under Additional Properties to load the list of cluster members</li> <li>Update weights from the list of cluster members and click Update</li> </ol> </TD> </TR> </TABLE>