Troubleshoot namespace problems
When developing or running applications, we might encounter namespace problems.
Many naming problems can be avoided by fully understanding the key underlying concepts of the Naming service.
Tasks
- Review the key concepts of the Naming service, especially the sections about Namespace logical view and Lookup names support in deployment descriptors and thin clients.
- Review the programming examples included in the sections explaining the JNDI and CosNaming interfaces.
- Read Naming service troubleshooting tips for additional general information.
- Read Application access problems for information on lookup errors.
Subtopics
- Naming service troubleshooting tips
Naming is a Java EE service which publishes and provides access to resources such as connection pools, enterprise beans, and message listeners to client processes. If we have problems in accessing a resource which otherwise appears to be healthy, the naming service might be involved.- Application access problems
To resolve problems encountered when a servlet, JavaServer Pages file, stand-alone application or other client attempts to access an enterprise bean, ConnectionPool, or other named object hosted by WAS, first verify that the target server can be accessed from the client.- View a namespace dump
To understand why a naming operation is failing, view the dump of a namespace. Use the dumpNameSpace tool to dump the contents of a namespace accessed through a name server. The dumpNameSpace tool is based on JNDI.- dumpNameSpace tool
Use the dumpNameSpace tool to dump the contents of a namespace accessed through a name server. The dumpNameSpace tool is based on JNDI.- View java:, local:, and server namespace dumps
To understand why a naming operation is failing, we can view the dump of a java: or local: namespace. From the WAS scripting tool, invoke a NameServer MBean to dump java: or local: namespaces.- Namespace dump utility for java:, local: and server namespaces
Sometimes it is helpful to dump the java: namespace for a Java EE application. We cannot use the dumpNameSpace command line utility for this purpose because the application's java: namespace is accessible only by that Java EE application. From the product scripting tool, we can invoke a NameServer MBean to dump the java: namespace for any Java EE application running in that same server process.
Related:
Namespace logical view Developing applications that use JNDI Developing applications that use CosNaming (CORBA Naming interface) Lookup names support in deployment descriptors and thin clients