Fix (APAR): PK50592 Status: Fix Release: 6.0.2.1 Operating System: AIX,HP-UX,Linux,Solaris,Windows,z/OS Supersedes Fixes: CMVC Defect: PK50592 Byte size of APAR: 11684 Date: 2007-12-05 Abstract: The On Demand Router is seen to not route any requests to the backend tier and all requests to the On Demand Router seem to get "stuck" at this tier. Description/symptom of problem: PK50592 resolves the following problem: ERROR DESCRIPTION: On startup, the On demand router is seen to not be routing any requests to the back-end application server cluster. The proxy.log and local.log of such an On Demand Router are seen to be devoid of requests and an analysis of the javacore shows a thread to be stuck in the following call stack, in an infinite loop. 3XMTHREADINFO "HAManager.thread.pool : 4" (TID:0x700000 0000F2F98, sys_thread_t:0x11BE96648, state:R, native ID:0x4E81) 4XESTACKTRACE at com.ibm.wsmm.rqm.Dispatcher. getNextQ(Dispatcher.java(Compiled Code)) 4XESTACKTRACE at com.ibm.wsmm.rqm.Dispatcher. fullNextQ(Dispatcher.java:540) 4XESTACKTRACE at com.ibm.wsmm.rqm.ReqQMgr$NC4 Fixup.take(ReqQMgr.java:879) 4XESTACKTRACE at com.ibm.wsmm.rqm.LoadBalancer. getInstance(LoadBalancer.java:238) 4XESTACKTRACE at com.ibm.wsmm.rqm.ReqQMgr.fixup (ReqQMgr.java:967) 4XESTACKTRACE at com.ibm.wsmm.rqm.ReqQMgr.setW eights(ReqQMgr.java:1574) 4XESTACKTRACE at com.ibm.wsmm.rqm.ReqQMgr.acces s$1400(ReqQMgr.java:100) 4XESTACKTRACE at com.ibm.wsmm.rqm.ReqQMgr$MyW fsReceiver.consumeSetWeights(ReqQMgr.java:1525) 4XESTACKTRACE at com.ibm.wsmm.comm.WeightsRecei verImpl$1.consume(WeightsReceiverImpl.java:65) 4XESTACKTRACE at com.ibm.ws.xd.comm.BBAdapterImpl $ConsumerWrapper.dispatch(BBAdapterImpl.java:731) 4XESTACKTRACE at com.ibm.ws.xd.comm.BBAdapterImpl $MySubjectSubscriptionEvents.dispatch(BBAdapterImpl.java:590) 4XESTACKTRACE at com.ibm.ws.xd.comm.BBAdapterImpl $MySubjectSubscriptionEvents.updated(BBAdapterImpl.java:683) 4XESTACKTRACE at com.ibm.ws.hamanager.bboard.Local BulletinBoardStateManager$BBoardUserCallback.doCallback (LocalBulletinBoardStateManager.java:1402) 4XESTACKTRACE at com.ibm.ws.hamanager.impl.Worker. run(UserCallbacks.java:278) 4XESTACKTRACE at com.ibm.ws.util.ThreadPool$Worker .run(ThreadPool.java(Compiled Code)) LOCAL FIX: PROBLEM SUMMARY USERS AFFECTED: All Users of WebSphere Extended Deployment 6.0.2 using the On Demand Router to route requests. PROBLEM DESCRIPTION: The On Demand Router is seen to not route any requests to the backend tier and all requests to the On Demand Router seem to get "stuck" at this tier. RECOMMENDATION: None A code bug in the Autonomic request flow manager component caused it to go into an infinite loop. This component is responsible for analyzing requests coming in to the On Demand Router and to prioritize and dispatch requests to the backend application server cluster tier based on the relative priority of incoming requests and the load on the backend tier. The infinite loop in this component caused it to become non-functional and hence it stops dispatching requests to the backend application server tier. This has the effect of causing all requests to the On Demand Router to get "stuck" at this tier, and these requests do not surface in either the proxy.log or the local.log files of the On Demand Router. PROBLEM CONCLUSION: The bug reported in this problem has been fixed and a fix for this problem is being made available for WebSphere Extended Deployment version 6.0.2.1. This code fix will also be included in fixpack 6.0.2.2 of WebSphere Extended Deployment. Directions to apply fix: Install Fix to: NOTE: Developers - Place and X next to the proper installation method and remove this note __ Application Server Nodes __ Deployment Manager Nodes _x_ Both NOTE: The user must have Administrative rights in Windows, or be the Actual Root User in a UNIX environments. Also, you should be logged in with the same authority level when unpacking a fix, fix pack or refresh pack. DOWNLOAD THE UPDATE INSTALLER TOOL IN ORDER TO INSTALL A FIX. The Fix Installer can be downloaded from the following link: http://www.ibm.com/support/docview.wss?rs=180&uid=swg21205991 The Update Installer for V5.0 does not have a maintenance directory. It uses fixpacks and fixes as the location of the unpacked files. Customers must be at V6.0.2.2 or newer of the Update Installer. This can be checked by reviewing the level of the Update Installer in file /updateinstaller/version.txt. 1) Copy PKxxxxx.pak file directly to the maintenance directory 2) Shutdown WebSphere Manually execute setupCmdLine.bat in Windows or . ./setupCmdLine.sh in Unix from the WebSphere instance that maintenance is being applied to. 3) Launch Update Installer 4) Enter the installation location of the WebSphere product you want to update. 5) Select the "Install maintenance package" operation. 6) Enter the file name of the maintenance package to install (PKxxxxx.pak file which was copied in the maintenance directory). The V5.0 and V5.1 fix packs and fixes are unpacked as .jar files and should be unpacked into fixpacks or fixes directory. 7) Install the maintenance package. 8) Restart WebSphere Directions to remove fix: NOTE: The user must have Administrative rights in Windows, or be the Actual Root User in a UNIX environments. NOTE: FIXES MUST BE REMOVED IN THE ORDER THEY WERE APPLIED. DO NOT REMOVE A FIX UNLESS ALL FIXES APPLIED AFTER IT HAVE FIRST BEEN REMOVED. YOU MAY REAPPLY ANY REMOVED FIX. Example: If your system has fix1, fix2, and fix3 applied in that order and fix2 is to be removed, fix3 must be removed first, fix2 removed, and fix3 re-applied. 1) Shutdown WebSphere Manually execute setupCmdLine.bat in Windows or . ./setupCmdLine.sh in Unix from the WebSphere instance that uninstall is being run against. 2) Start Update Installer 3) Enter the installation location of the WebSphere product you want to remove the fix. 4) Select "Uninstall maintenance package" operation. 5) Enter the file name of the maintenance package to uninstall (PKxxxxx.pak). 6) UnInstall maintenance package. 7) Restart WebSphere Directions to re-apply fix: 1) Shutdown WebSphere 2) Follow the Fix instructions to apply the fix. 3) Restart WebSphere Additional Information: