Understanding FFDC log files

When your running your websphere application server you will see this type of messages in your SystemOut.log file or in the console of your RAD saying that FFDC incident stream file is opened.


[6/24/09 17:21:07:125 PDT] 0000000a ServiceLogger I com.ibm.ws.ffdc.IncidentStreamImpl initialize FFDC0009I: FFDC opened incident stream file C:\IBM\WebSphere\wp_profile\logs\ffdc\WebSphere_Portal_0000000a_09.06.24_17.21.07_0.txt
[6/24/09 17:21:07:140 PDT] 0000000a ServiceLogger I com.ibm.ws.ffdc.IncidentStreamImpl resetIncidentStream FFDC0010I: FFDC closed incident stream file C:\IBM\WebSphere\wp_profile\logs\ffdc\WebSphere_Portal_0000000a_09.06.24_17.21.07_0.txt


This line indicates that some abnormal condition happened and a FFDC log has been created for that error. You can safely ignore this message. There are two artifacts which are produced by FFDC, the information can be located in the <profileroot>/logs/FFDC directory:

• Exception Logs:<ServerName>_Exception.log
  
• Incident Stream:<ServerName>_<threadid>_<timeStamp>_<SequenceNumber>.txt

The first file <ServerName>_Exception.log has one entry each for all the FFDC incidents that happened since the server started. So most of the data in this file is old. This is how a sample entry in <ServerName>_Exception.log file looks like

 Index  Count   Time of last Occurrence   Exception SourceId ProbeId
------+------+---------------------------+--------------------------
     1      1    6/19/09 17:26:15:686 PDT java.util.zip.ZipException com.ibm.ws.classloader.ClassLoaderUtils.addDependents 238
------+------+---------------------------+--------------------------

The incident stream contains more details about exceptions which have been encountered during the running of the server. One indecent file would be created for every indecent with detailed thread dump of the thread in which exception occurred. This is how a sample incident file looks like

------Start of DE processing------ = [6/26/09 9:03:07:161 PDT] , key = java.util.zip.ZipException com.ibm.ws.classloader.ClassLoaderUtils.addDependents 238
Exception = java.util.zip.ZipException
Source = com.ibm.ws.classloader.ClassLoaderUtils.addDependents
probeid = 238
Stack Dump = java.util.zip.ZipException: Bad file descriptor C:\IBM\WebSphere\PortalServer\lwp04.infra\sync.infra\syncmlbase\shared\app\lotusworkplacelib\eclipse-runtime.jar
 at java.util.zip.ZipFile.open(Native Method)
 at java.util.zip.ZipFile.(ZipFile.java:238)
 at java.util.jar.JarFile.(JarFile.java:169)
 at java.util.jar.JarFile.(JarFile.java:107)
 at com.ibm.ws.classloader.ClassLoaderUtils.addDependents(ClassLoaderUtils.java:99)
 at com.ibm.ws.classloader.ClassLoaderUtils.addDependents(ClassLoaderUtils.java:146)
 at com.ibm.ws.classloader.ClassLoaderUtils.addDependents(ClassLoaderUtils.java:146)
 at com.ibm.ws.classloader.ClassLoaderUtils.addDependentJars(ClassLoaderUtils.java:60)
 at com.ibm.ws.runtime.component.ApplicationServerImpl.initializeClassLoader(ApplicationServerImpl.java:278)
 at com.ibm.ws.runtime.component.ApplicationServerImpl.initialize(ApplicationServerImpl.java:136)
 at com.ibm.ws.runtime.component.ContainerImpl.initializeComponent(ContainerImpl.java:1338)
 at com.ibm.ws.runtime.component.ContainerImpl.initializeComponents(ContainerImpl.java:1171)
 at com.ibm.ws.runtime.component.ServerImpl.initialize(ServerImpl.java:356)
 at com.ibm.ws.runtime.WsServerImpl.bootServerContainer(WsServerImpl.java:178)
 at com.ibm.ws.runtime.WsServerImpl.start(WsServerImpl.java:140)
 at com.ibm.ws.runtime.WsServerImpl.main(WsServerImpl.java:461)
 at com.ibm.ws.runtime.WsServer.main(WsServer.java:59)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:79)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
 at java.lang.reflect.Method.invoke(Method.java:618)
 at com.ibm.wsspi.bootstrap.WSLauncher.launchMain(WSLauncher.java:183)
 at com.ibm.wsspi.bootstrap.WSLauncher.main(WSLauncher.java:90)
 at com.ibm.wsspi.bootstrap.WSLauncher.run(WSLauncher.java:72)
 at org.eclipse.core.internal.runtime.PlatformActivator$1.run(PlatformActivator.java:78)
 at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:92)
 at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:68)
 at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:400)
 at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:177)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:79)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
 at java.lang.reflect.Method.invoke(Method.java:618)
 at org.eclipse.core.launcher.Main.invokeFramework(Main.java:336)
 at org.eclipse.core.launcher.Main.basicRun(Main.java:280)
 at org.eclipse.core.launcher.Main.run(Main.java:977)
 at com.ibm.wsspi.bootstrap.WSPreLauncher.launchEclipse(WSPreLauncher.java:336)
 at com.ibm.wsspi.bootstrap.WSPreLauncher.main(WSPreLauncher.java:91)

Dump of callerThis = 
null

Exception = java.util.zip.ZipException
Source = com.ibm.ws.classloader.ClassLoaderUtils.addDependents
probeid = 238
Dump of callerThis = 
null

You can relate the incident file with the exception.log file by taking the probeid from the incident file and searching for it in the exception.log file. You will notice that timestamps also match.