Configuring Shared Libraries for Enterprise Applications in V5
 Technote (troubleshooting)
 
Problem(Abstract)
Shared libraries are used to load dependent jar or class files used by enterprise applications. This document describes how to configure shared libraries and problems you may encounter.
 
Resolving the problem
You can define a shared library at the cell, node, or application server level. Defining a library at one of the three levels does not cause the library to be placed into the application server class loader. You must associate the library with an application or server in order for the classes represented by the shared library to be loaded in either a server-wide or application-specific class loader.

Configuring shared libraries using the administrative console

Open the administrative console to the Environment menu and choose the Shared Libraries link. Here you will add the new shared library location reference for enterprise applications to use. Once you create the reference in the Shared Libraries, then the reference can be added to the enterprise application. Go the Applications menu and choose the Enterprise Applications link. This is where you pick the enterprise applications that need this reference. After you click on the link for the specific enterprise application then you will look at the Additional Properties in the Config tab and click on the Libraries link. Here is where the reference of the shared library is added to the specific application server.

Files to look for:

The libraries.xml is created and located based on the scope. The file will be created in the following location depending on scope:

  • Application server level - the file will be located in the $WAS_HOME/config/cells/<cell name>/nodes/<node name>/servers/<specific server name> directory.

  • Node level - the file will be located in the $WAS_HOME/config/cells/<cell name>/nodes/<node name> directory.

  • Cell level - the file will be located in the $WAS_HOME/config/cells/<cell name> directory.

The deployment.xml file for the enterprise application (located in the $WAS_HOME/config/cells/<cell name>/applications/name.ear/deployments/name.ear directory) that needs the shared libraries information will have a tag similar to the following added to the classloader section:


<classloader xmi:id="Classloader_1" mode="PARENT_FIRST">
<libraries xmi:id="LibraryRef_1" libraryName="sharelib"/>
</classloader>

Potential Problems:

Not Loading: The application server or enterprise application that a shared library reference is mapped to needs to be recycled to load the new classes.

Example: If you create a shared library reference and map this to an application server that is running, it will need to be stopped and restarted before the shared library files will be accessible. This also applies when mapping to enterprise applications.

Save Changes: After you create the shared libraries reference you will have to save the configuration to the master repository. At the top menu bar press the Save link to save the configuration.

Note: if you are using the Network Deployment Manager administrative console it is best to check Synchronize Nodes when saving to make sure the information is propagated to all the nodes.

Synchronization: If you have nodes federated to a Network Deployment Manager, the changes to a node need to be propagated from the Network Deployment Manager by synchronizing. This can happen either automatically, by waiting for a specified synchronization interval, or manually by going to the System Properties and choosing the Nodes link. Check the node you want and press either Synchronization or Full Synchronization buttons. Now you should see the new configuration changes to the node when looking in the $WAS_HOME/config directory.

Scope Level: Look at the "Scope Level: Cells=<cell name>....". What the title of the scope level states is the location where the modifications will happen. Even if you change the information below the scope level title to point at the location you want, without pressing the Apply button, changing the scope and scope title, the modification will not be where you want them.

If You Still Have Problems: Run the collector tool and call 1-800-IBM-SERV for further support from IBM. Document the steps you did so we can recreate this.

 
 
Cross Reference information
Segment Product Component Platform Version Edition
Application Servers Runtimes for Java Technology Java SDK
 
 


Document Information


Product categories: Software > Application Servers > Distributed Application & Web Servers > WebSphere Application Server > Classloader
Operating system(s): Windows
Software version: 5.0
Software edition:
Reference #: 1084041
IBM Group: Software Group
Modified date: Dec 23, 2003