WebSphere Application Server fail to start after applying the MQSeries patch D71433_MQ53_CSD1.jar
 Technote (troubleshooting)
 
Problem(Abstract)
After installing the MQSeries® patch in /opt/mqm/java/lib and adding the patch to the WebSphere® Application Server JVM™ classpath the Application Server failed to start with error:

wsServer E WSVR0003E:Server server1 failed to start com.ibm.ws.exception.RuntimeError
 
Cause
The MQSeries patch should not be added to the Application Server classpath.
 
Resolving the problem
The Application Server classpath is not the place to add the MQSeries patch. The WebSphere Application Server classloader have the following hierarchy:
  1. Bootstrap ClassLoader
  2. WebSphere Application Server ClassLoader
  3. Application ClassLoader

Role of each classloader:

  • The bootstrap classloader loads the built in Java™ SDK classes plus whatever is on the classpath.
  • The WebSphere Application Server classloader loads the WebSphere Application Server libraries (such as, install_root/lib/*.jar) as well as the resource providers jar files (such as, MQ and JDBC drivers).
  • The application classloader(s) loads the actual application ear files.

Classloaders are hierarchical in nature. For example, a class loaded by the WebSphere Application Server classloader can see the classes loaded by bootstrap, but not vice versa.

The problem is that the MQSeries patch is loaded by bootstrap classloader. However the patch is for a class loaded by the WebSphere Application Server classloader (The MQ JMS provider ). The patch must reference classes contained in the WebSphere Application Server classloader and it is unable to load it.

To fix this problem:

  • Remove entry for the MQSeries patch from the operating system's CLASSPATH variable
  • Insert the patch by update the WAS_EXT_DIRS variable found in install_root/bin/setupCmdLine.sh
    (such as, /opt/WebSphere/AppServer/bin/setupCmdLine.sh).

    The patch should be added to the beginning of the variable.
 
 
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 #: 1109901
IBM Group: Software Group
Modified date: Sep 30, 2004