clustering: Openfire admin console page 'conversations' can fail

Question

clustering: Openfire admin console page 'conversations' can fail

Closed this issue 3 years ago · 2 comments

When the plugin is installed on all cluster nodes, and on a junior cluster node, the Server > Archiving > Conversations page is opened, then a blank page is shown and the following exceptions are logged.

This problem does not occur on the senior cluster node.

This problem does not occur when there are no active conversations.

2020.09.09 14:17:21 ERROR [Jetty-QTP-AdminConsole-125]: org.jivesoftware.openfire.plugin.util.cache.ClusteredCacheFactory - Failed to execute cluster task
com.hazelcast.nio.serialization.HazelcastSerializationException: Problem while reading Externalizable class: org.jivesoftware.openfire.archive.Conversation, exception: java.io.IOException: java.lang.ClassNotFoundException: org.jivesoftware.openfire.archive.UserParticipations
        at com.hazelcast.internal.serialization.impl.JavaDefaultSerializers$ExternalizableSerializer.read(JavaDefaultSerializers.java:159) ~[?:?]
        at com.hazelcast.internal.serialization.impl.JavaDefaultSerializers$ExternalizableSerializer.read(JavaDefaultSerializers.java:135) ~[?:?]
        at com.hazelcast.internal.serialization.impl.StreamSerializerAdapter.read(StreamSerializerAdapter.java:48) ~[?:?]
        at com.hazelcast.internal.serialization.impl.AbstractSerializationService.readObject(AbstractSerializationService.java:269) ~[?:?]
        at com.hazelcast.internal.serialization.impl.ByteArrayObjectDataInput.readObject(ByteArrayObjectDataInput.java:574) ~[?:?]
        at com.hazelcast.internal.serialization.impl.ArrayListStreamSerializer.read(ArrayListStreamSerializer.java:49) ~[?:?]
        at com.hazelcast.internal.serialization.impl.ArrayListStreamSerializer.read(ArrayListStreamSerializer.java:31) ~[?:?]
        at com.hazelcast.internal.serialization.impl.StreamSerializerAdapter.read(StreamSerializerAdapter.java:48) ~[?:?]
        at com.hazelcast.internal.serialization.impl.AbstractSerializationService.readObject(AbstractSerializationService.java:269) ~[?:?]
        at com.hazelcast.internal.serialization.impl.ByteArrayObjectDataInput.readObject(ByteArrayObjectDataInput.java:574) ~[?:?]
        at com.hazelcast.spi.impl.operationservice.impl.responses.NormalResponse.readData(NormalResponse.java:111) ~[?:?]
        at com.hazelcast.internal.serialization.impl.DataSerializableSerializer.readInternal(DataSerializableSerializer.java:160) ~[?:?]
        at com.hazelcast.internal.serialization.impl.DataSerializableSerializer.read(DataSerializableSerializer.java:106) ~[?:?]
        at com.hazelcast.internal.serialization.impl.DataSerializableSerializer.read(DataSerializableSerializer.java:51) ~[?:?]
        at com.hazelcast.internal.serialization.impl.StreamSerializerAdapter.read(StreamSerializerAdapter.java:48) ~[?:?]
        at com.hazelcast.internal.serialization.impl.AbstractSerializationService.toObject(AbstractSerializationService.java:187) ~[?:?]
        at com.hazelcast.spi.impl.operationservice.impl.InvocationFuture.resolve(InvocationFuture.java:108) ~[?:?]
        at com.hazelcast.spi.impl.operationservice.impl.InvocationFuture.resolveAndThrowIfException(InvocationFuture.java:79) ~[?:?]
        at com.hazelcast.spi.impl.AbstractInvocationFuture.get(AbstractInvocationFuture.java:191) ~[?:?]
        at com.hazelcast.util.executor.DelegatingFuture.get(DelegatingFuture.java:88) ~[?:?]
        at org.jivesoftware.openfire.plugin.util.cache.ClusteredCacheFactory.doSynchronousClusterTask(ClusteredCacheFactory.java:459) ~[?:?]
        at org.jivesoftware.util.cache.CacheFactory.doSynchronousClusterTask(CacheFactory.java:724) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.jivesoftware.openfire.archive.ConversationManager.getConversations(ConversationManager.java:553) ~[?:?]
        at org.jivesoftware.openfire.plugin.monitoring.conversations_jsp._jspService(conversations_jsp.java:167) ~[?:?]
        at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) ~[apache-jsp-8.5.49.jar:8.5.49]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) ~[javax.servlet-api-3.1.0.jar:3.1.0]
        at org.jivesoftware.openfire.container.PluginServlet.handleJSP(PluginServlet.java:439) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.jivesoftware.openfire.container.PluginServlet.service(PluginServlet.java:129) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) ~[javax.servlet-api-3.1.0.jar:3.1.0]
        at org.eclipse.jetty.servlet.ServletHolder$NotAsyncServlet.service(ServletHolder.java:1411) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:763) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1631) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.jivesoftware.admin.PluginFilter.doFilter(PluginFilter.java:226) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1618) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.jivesoftware.admin.AuthCheckFilter.doFilter(AuthCheckFilter.java:234) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1618) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at com.opensymphony.sitemesh.webapp.SiteMeshFilter.obtainContent(SiteMeshFilter.java:129) ~[sitemesh-2.4.2.jar:?]
        at com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:77) ~[sitemesh-2.4.2.jar:?]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1618) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.jivesoftware.util.LocaleFilter.doFilter(LocaleFilter.java:73) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1618) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.jivesoftware.util.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:49) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1618) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.jivesoftware.admin.PluginFilter.doFilter(PluginFilter.java:226) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1618) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.jivesoftware.admin.AuthCheckFilter.doFilter(AuthCheckFilter.java:234) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1610) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:549) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:602) ~[jetty-security-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:127) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:235) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1610) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:233) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1363) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:188) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:489) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1580) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:186) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1278) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:221) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:146) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:127) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.Server.handle(Server.java:500) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.HttpChannel.lambda$handle$1(HttpChannel.java:383) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.HttpChannel.dispatch(HttpChannel.java:547) [jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:375) [jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:273) [jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:311) [jetty-io-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:103) [jetty-io-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:117) [jetty-io-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:336) [jetty-util-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:313) [jetty-util-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:171) [jetty-util-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:129) [jetty-util-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:375) [jetty-util-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:806) [jetty-util-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:938) [jetty-util-9.4.28.v20200408.jar:9.4.28.v20200408]
        at java.lang.Thread.run(Thread.java:748) [?:1.8.0_252]
2020.09.09 14:17:21 ERROR [Jetty-QTP-AdminConsole-125]: org.jivesoftware.openfire.container.PluginServlet - null
java.lang.NullPointerException: null
        at org.jivesoftware.openfire.plugin.monitoring.conversations_jsp._jspService(conversations_jsp.java:183) ~[?:?]
        at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) ~[apache-jsp-8.5.49.jar:8.5.49]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) ~[javax.servlet-api-3.1.0.jar:3.1.0]
        at org.jivesoftware.openfire.container.PluginServlet.handleJSP(PluginServlet.java:439) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.jivesoftware.openfire.container.PluginServlet.service(PluginServlet.java:129) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) ~[javax.servlet-api-3.1.0.jar:3.1.0]
        at org.eclipse.jetty.servlet.ServletHolder$NotAsyncServlet.service(ServletHolder.java:1411) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:763) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1631) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.jivesoftware.admin.PluginFilter.doFilter(PluginFilter.java:226) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1618) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.jivesoftware.admin.AuthCheckFilter.doFilter(AuthCheckFilter.java:234) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1618) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at com.opensymphony.sitemesh.webapp.SiteMeshFilter.obtainContent(SiteMeshFilter.java:129) ~[sitemesh-2.4.2.jar:?]
        at com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:77) ~[sitemesh-2.4.2.jar:?]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1618) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.jivesoftware.util.LocaleFilter.doFilter(LocaleFilter.java:73) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1618) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.jivesoftware.util.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:49) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1618) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.jivesoftware.admin.PluginFilter.doFilter(PluginFilter.java:226) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1618) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.jivesoftware.admin.AuthCheckFilter.doFilter(AuthCheckFilter.java:234) ~[xmppserver-4.6.0-SNAPSHOT.jar:4.6.0-SNAPSHOT]
        at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1610) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:549) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:602) ~[jetty-security-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:127) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:235) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1610) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:233) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1363) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:188) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:489) ~[jetty-servlet-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1580) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:186) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1278) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:221) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:146) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:127) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.Server.handle(Server.java:500) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.HttpChannel.lambda$handle$1(HttpChannel.java:383) ~[jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.HttpChannel.dispatch(HttpChannel.java:547) [jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:375) [jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:273) [jetty-server-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:311) [jetty-io-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:103) [jetty-io-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:117) [jetty-io-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:336) [jetty-util-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:313) [jetty-util-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:171) [jetty-util-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:129) [jetty-util-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:375) [jetty-util-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:806) [jetty-util-9.4.28.v20200408.jar:9.4.28.v20200408]
        at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:938) [jetty-util-9.4.28.v20200408.jar:9.4.28.v20200408]
        at java.lang.Thread.run(Thread.java:748) [?:1.8.0_252]

Answer 1 · 2020-09-09T14:23:54.000Z

Also reported by @annovanvliet at https://discourse.igniterealtime.org/t/classnotfoundexception-userparticipations-when-retrieving-active-conversations-in-a-cluster/ as well as by another community member at https://discourse.igniterealtime.org/t/cluster-problem/86031/

Answer 2 · 2021-12-07T16:23:03.000Z

This issue will be prevented by the fixes for igniterealtime/openfire-hazelcast-plugin#79, igniterealtime/openfire-hazelcast-plugin#81 and OF-2350. However, none of these will prevent a very similar issue that occurs when reloading or updating the plugin without an Openfire restart (the issue that is warned for with igniterealtime/openfire-hazelcast-plugin#74)