Check the Server Version Numbers Check the Multicast Address Check the CLASSPATH Value

12 Troubleshooting Common Problems 12-1 12 Troubleshooting Common Problems This chapter provides guidelines on how to prevent cluster problems or troubleshoot them if they do occur. For information about troubleshooting IP multicast configuration problems, see Chapter 13, Troubleshooting Multicast Configuration.

12.1 Before You Start the Cluster

You can do a number of things to help prevent problems before you boot the cluster.

12.1.1 Check the Server Version Numbers

All servers in the cluster must have the same major version number, but can have different minor version numbers and service packs. The clusters Administration Server is typically not configured as a cluster member, but it should run the same major version of WebLogic Server used on the Managed Servers.

12.1.2 Check the Multicast Address

A problem with the multicast address is one of the most common reasons a cluster does not start or a server fails to join a cluster. A multicast address is required for each cluster. The multicast address can be an IP number between 224.0.0.0 and 239.255.255.255, or a host name with an IP address within that range. You can check a clusters multicast address and port on its Configuration Multicast page in the Administration Console. For each cluster on a network, the combination of multicast address and port must be unique. If two clusters on a network use the same multicast address, they should use different ports. If the clusters use different multicast addresses, they can use the same port or accept the default port, 7001. Before booting the cluster, make sure the clusters multicast address and port are correct and do not conflict with the multicast address and port of any other clusters on the network. The errors you are most likely to see if the multicast address is bad are: Unable to create a multicast socket for clustering Multicast socket send error Multicast socket receive error 12-2 Using Clusters for Oracle WebLogic Server

12.1.3 Check the CLASSPATH Value

Make sure the value of CLASSPATH is the same on all Managed Servers in the cluster. CLASSPATH is set by the setEnv script, which you run before you run startManagedWebLogic to start the Managed Servers. By default, setEnv sets this value for CLASSPATH as represented on Windows systems: set WL_HOME=C:\bea\wlserver_10.00 set JAVA_HOME=C:\bea\jdk131 . . set CLASSPATH=JAVA_HOME\lib\tools.jar; WL_HOME\server\lib\weblogic_sp.jar; WL_HOME\server\lib\weblogic.jar; CLASSPATH If you change the value of CLASSPATH on one Managed Server, or change how setEnv sets CLASSPATH, you must change it on all Managed Servers in the cluster.

12.2 After You Start the Cluster