PQ79098: NullPointerException observed when using Session Memory-to-memory replication | |||||||||||||||||||||||||||||||||||||||
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![]() APAR status Closed as program error. Error description When using session with memory-to-memory replication for failover, NullpointerExceptions are observed in the Application Server logs. This may also result in failover not happening as expected with the Session Manager creating new sessions instead of returning existing ones after an application server that holds the original session is brought down. The text of the exception might look like this. [7/7/03 1:23:45:670 CDT] 464d6b2a DRSCacheApp E DRSW0008E: Exception is: java.lang.NullPointerException at com.ibm.ws.webcontainer.util.SimpleHashtable.get(SimpleHashtable .java(Compiled Code)) at com.ibm.ws.webcontainer.httpsession.SessionContextRegistry.getSe ssionContextByName(SessionContextRegistry.java(Inlined Compiled Code)) at com.ibm.ws.webcontainer.httpsession.DRSHttpSessCache.acknowledge (DRSHttpSessCache.java(Compiled Code)) at com.ibm.ws.drs.DRSJMS.onMessage(DRSJMS.java(Compiled Code))Local fix Problem summary **************************************************************** * USERS AFFECTED: All WebSphere Application Server users. * **************************************************************** * PROBLEM DESCRIPTION: A NullPointerException is seen in DRS * * logs on a receipt of a DRS ack message. * **************************************************************** * RECOMMENDATION: * **************************************************************** When changes are made to an existing sessiong a DRS instance sends back an ack message as a response to a received removeEntry message. In this returning ack, the propkey contains the application name whose session is to be removed. A null propkey is encountered in a received ack, and this causes a NullPointerException.Problem conclusion The cause of the problem was a dca.retDCMPool statement that was being invoked twice on the same DCM, causing two references of the same DCM to be entered into the DCMPool.Temporary fix Comments
APAR is sysrouted FROM one or more of the following: PQ76310 APAR is sysrouted TO one or more of the following: Modules/Macros
SRLS
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Document Information |
Product categories: Software > Application Servers >
Distributed Application & Web Servers > WebSphere Application
Server > General
Operating system(s):
Software version: 400
Software edition:
Reference #: PQ79098
IBM Group: Software Group
Modified date: Oct 1, 2003
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