Hi Are there other error or exception in your log?
Please show us your cluster configuration in your server.xml. e.g. - What is mapSendOptions? - Which Interceptor do you use? 2015-04-15 3:55 GMT+09:00 Théo Chamley <theo...@mley.fr>: > Hello, > > I have a working Tomcat 8.0.15 cluster with 3 members with the > BackupManager as session manager. > The session replication is mostly working except in a few cases. In those > cases, I get the following error: > > 09-Apr-2015 12:16:58.369 SEVERE [Tribes-Task-Receiver-6] > org.apache.catalina.tribes.tipis.AbstractReplicatedMap.messageReceived > Unable to apply diff to key:3B286B4C7CA060163A00988969D21923 > java.lang.NullPointerException > at > org.apache.catalina.ha.session.DeltaSession.applyDiff(DeltaSession.java:164) > at > org.apache.catalina.tribes.tipis.AbstractReplicatedMap.messageReceived(AbstractReplicatedMap.java:664) > at > org.apache.catalina.tribes.group.GroupChannel.messageReceived(GroupChannel.java:293) > at > org.apache.catalina.tribes.group.ChannelInterceptorBase.messageReceived(ChannelInterceptorBase.java:81) > at > org.apache.catalina.tribes.group.interceptors.TcpFailureDetector.messageReceived(TcpFailureDetector.java:112) > at > org.apache.catalina.tribes.group.ChannelInterceptorBase.messageReceived(ChannelInterceptorBase.java:81) > at > org.apache.catalina.tribes.group.ChannelInterceptorBase.messageReceived(ChannelInterceptorBase.java:81) > at > org.apache.catalina.tribes.group.interceptors.ThroughputInterceptor.messageReceived(ThroughputInterceptor.java:89) > at > org.apache.catalina.tribes.group.ChannelInterceptorBase.messageReceived(ChannelInterceptorBase.java:81) > at > org.apache.catalina.tribes.group.ChannelCoordinator.messageReceived(ChannelCoordinator.java:260) > at > org.apache.catalina.tribes.transport.ReceiverBase.messageDataReceived(ReceiverBase.java:240) > at > org.apache.catalina.tribes.transport.nio.NioReplicationTask.drainChannel(NioReplicationTask.java:206) > at > org.apache.catalina.tribes.transport.nio.NioReplicationTask.run(NioReplicationTask.java:97) > at > java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) > at > java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) > at java.lang.Thread.run(Thread.java:745) > > > I was able to replicate the problem with a scenario in the application, > but I was not able to understand the underlying problem. > This happens when the user is making a very specific request and this > request arrives on a Tomcat where his session is not stored, forcing the > Tomcat to fetch the session elsewhere. > > The 3 tomcats are on the same network with a very low network latency. > > Does anybody has some advice on how to debug this problem? > > For now, I got around it with sticky sessions on mod_jk, but I find this > very unsatisfactory. > > Thank you in advance for your help, > > //Théo > > -- > Keiichi.Fujino >
