Fails to start weblogic instances maintenance of Admin server as well as all managed servers etc. Troubleshooting in weblogic is found out the cause(Server fail, Server shutdown, SSL issue, Thread stuck, etc…) of WebLogic server failure if it occurs by servers logs
You can do several things to help prevent problems before you boot the cluster.
Your WebLogic Server license must include the clustering feature. If you try to start a cluster without a clustering license, you will see the error message Unable to find a license for clustering.
All Managed Servers in a cluster and the cluster's Administration Server should run under the same version of WebLogic Server. The major and minor version numbers (e.g 9.1), service packs, and attached patch levels should be the same across the cluster.
a) A problem with the multicast address is one of the most common reasons a cluster does not start or a server fails to join a cluster.
b) A multicast address is required for each cluster. The multicast address can be an IP number between 224.0.0.0 and 239.255.255.255, or a hostname with an IP address within that range.
c) You can check a cluster's multicast address and port on its Configuration-->Multicast tab in the Administration Console.
d) For each cluster on a network, the combination of a multicast address and port must be unique. If two clusters on a network use the same multicast address, they should use different ports. If the clusters use different multicast addresses, they can use the same port or accept the default port, 7001.
e) Before booting the cluster, make sure the cluster's multicast address and port are correct and do not conflict with the multicast address and port of any other clusters on the network.
f) The errors you are most likely to see if the multicast address is bad are:
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Make sure the value of CLASSPATH is the same on all managed servers in the cluster. CLASSPATH is set by the setEnv script, which you run before you run startManagedWebLogic to start the managed servers.
By default, setEnv sets this value for CLASSPATH (as represented on Windows systems):
set WL_HOME=C:beaweblogic700
set JAVA_HOME=C:beajdk131
.
.
set CLASSPATH=%JAVA_HOME%libtools.jar;
%WL_HOME%serverlibweblogic_sp.jar;
%WL_HOME%serverlibweblogic.jar;
%CLASSPATH%
If you change the value of CLASSPATH on one managed server or change how setEnv sets CLASSPATH, you must change it on all managed servers in the cluster.
Each server instance in the cluster has a default execute queue, configured with a fixed number of executing threads. To view the thread count for the default execute queue, choose the Configure Execute Queue command on the Advanced Options portion of the Configuration> General tab for the server. The default thread count for the default queue is 15, and the minimum value is 5. If the value of Thread Count is below 5, change it to a higher value so that the Managed Server does not hang on startup.
This section describes the first troubleshooting steps to perform if you have problems trying to start a cluster.
If the cluster fails to start, or a server fails to join the cluster, the first step is to check any commands you have entered, such as startManagedWebLogic or a java interpreter command, for errors and misspellings.
If you use the JRockit JVM under Linux, use one of the following methods to generate a thread dump.
To obtain the root PID, perform a: ps -efHl | grep 'java' **. **
Using a grep argument that is a string that will be found in the process stack that matches the server startup command. The first PID reported will be the root process, assuming that the ps command has not been piped to another routine.
Under Linux, each executing thread appears as a separate process under the Linux process stack. To use Kill -3 on Linux you supply must match the PID of the main WebLogic execute thread, otherwise, no thread dump will be produced.
If you are experiencing cluster problems, you should also check the garbage collection on the managed servers. If garbage collection is taking too long, the servers will not be able to make the frequent heartbeat signals that tell the other cluster members they are running and available.
If garbage collection (either first or second-generation) is taking 10 or more seconds, you need to tune heap allocation (the ms mx parameter) on your system.
Everything visible through the Weblogic admin console (http://localhost:7001/console) can be accessed through a command line java tool. This tool can be used to gather data about the weblogic servers via scripting. There are at least two ways to get runtime monitoring data about Weblogic processes. This document covers the use of the java classes that get information from management beans (mbeans). There is also a java tool that allows for browsing the mbean tree like an ftp client: Weblogic Scripting Tool (WLST).
There is a script for setting the CLASSPATH and PATH so that this tool can work. On pitblade (WL Server), the setWLSEnv script is /dsk2/local/bea81/weblogic81/server/bin/setWLSEnv.sh
pitblade:II:root: > source setWLSEnv.sh
CLASSPATH=/dsk2/local/bea81/jdk141_02/lib/tools.jar:/dsk2/local/bea81/weblogic81/server/lib/weblogic_sp.jar:
/dsk2/local/bea81/weblogic81/server/lib/weblogic.jar:/dsk2/local/bea81/weblogic81/server/lib/ojdbc14.jar:
:/dsk1/AdvIngres/ing26/ingres/lib/edbc.jar:/dsk1/AdvIngres/ing26/ingres/lib/edbc.jar
PATH=/dsk2/local/bea81/weblogic81/server/bin:/dsk2/local/bea81/jdk141_02/jre/bin:/dsk2/local/bea81/jdk141_02/bin:
/dsk1/AdvIngres/ing26/ingres/bin:/dsk1/AdvIngres/ing26/ingres/utility:/dsk1/AdvIngres/ing26/ingres/files:
/dsk1/AdvIngres/ing26/ingres/lib:/dsk1/AdvIngres/ing26/ingres/SUNWspro/bin:/sbin:/usr/sbin:/bin:/usr/bin:
/usr/ucb:/etc:/usr/etc:/opt/fw/bin:/var/adm/psmfc/bin:/usr/openwin/bin:/usr/local/bin:/usr/psmfc/bin:
/usr/ccs/bin:/usr/lib/nis:/opt/gnu/bin:/usr/local/bin
Your environment has been set.
pitblade:II:root: > java weblogic.Admin
weblogic.Admin is a command-line utility for managing WebLogic Server. Try:
weblogic.Admin help LIFECYCLE Starting, stopping, discovering servers
weblogic.Admin help INFO Retrieving info about WebLogic Server
weblogic.Admin help JDBC Working with JDBC connection pools
weblogic.Admin help MBEAN Working with WebLogic Server MBeans
weblogic.Admin help CLUSTER Working with clusters
weblogic.Admin help ALL Help for all commands
Usage: java [<SSL trust options>] weblogic.Admin
[ [-url | -adminurl] [<protocol>://]<listen-address>:<port>]
-username <username> -password <password>
<COMMAND> <ARGUMENTS>
More info available at: http://e-docs.bea.com/wls/docs81/admin_ref/cli.html
pitblade:II:root: > java weblogic.Admin
Exception in thread "main" java.lang.NoClassDefFoundError: weblogic/Admin
pitblade:II:root: > java weblogic.Admin -username user -password pass GETSTATE myserver
Current state of "myserver" : RUNNING
pitblade:II:root: > java weblogic.Admin -username user -password pass GET -pretty -type Server
---------------------------
MBeanName: "mydomain:Name=myserver,Type=Server"
AcceptBacklog: 50
AdministrationPort: 0
AutoKillIfFailed: false
AutoRestart: true
COM: myserver
COMEnabled: false
CachingDisabled: true
On command prompt issue this command:
ps -if | grep java
You should get a response like this:
reedi.psmfc.org:C1:root: > ps -eaf | grep java
root 6233 6221 0 Jan 31 ? 2:50 /usr/local/bea81/jdk141_02/bin/java -server -Xms32m -Xmx200m -XX:MaxPermSize=12
root 6273 6261 0 Jan 31 ? 361:59 /usr/local/bea81/jdk141_02/bin/java -server -Xms256m -Xmx512m -Djava.awt.headle
root 1121 6273 0 Feb 08 ? 15:29 /usr/local/bea81/jdk141_02/jre/bin/java -Xms256m -Xmx1024m -cp /global/ds1/pitw
root 2087 20643 0 13:44:11 pts/1 0:00 grep java
cd /usr/local/bea81/user_projects/mydomain2
nohup ./startManagedWebLogic.sh &
cd /dsk2/local/bea81/user_projects/mydomain
nohup ./startWeblogic.sh &
On pitblade(server), the file /tmp/wlproxy.log is filling the filesystem and crashing the server. Apparently, this file is debugged information generated by apache about the weblogic proxy plug-in. It probably causes a severe drain on resources and should not be generally active. Here is the relevant stanza from httpd.conf:
Note: The specified location of the log file seems to be ignored. There would not have been a problem if the log file was actually located where it was directed in the configuration.
<IfModule mod_weblogic.c>
WebLogicHost pitblade
WebLogicPort 7001
MatchExpression *.jsp
#MatchExpression /ptagis/home/regTagAction
WebLogicHost=pitblade|WebLogicPort=7001|Idempotent=OFF
Debug ON
WLLogFile /var/log/bea/wlproxy.log
HungServerRecoverSecs 30000
</IfModule>
After changing this setting, apache needs a restart like this:
apache2/bin/apachectl restart
Turned off this debugging output on pitblade and bay. The response time seems better as a result.
While there are many possible causes of performance degradation or hangs, this article can't possibly cover them all. Instead, we'll look at three common mistakes in WebLogic Server applications that can deadlock the server or bring your performance to a screeching halt.
The best Java tool for diagnosing deadlocks is a Java virtual machine thread dump. A thread dump is a snapshot of the virtual machine's current state, including stack traces for each Java thread. Many virtual machines also include information about the Java monitors held by each thread. Monitor information is especially useful for diagnosing deadlocks and performance problems in your application. On Windows platforms, you can generate a thread dump by pressing Ctrl-Break in the virtual machine's window. On Unix systems, a SIGQUIT signal must be sent to the Java virtual machine process. This can be done with a kill -3 <process id>.
Another common way to deadlock an application is what I call the "out of threads" deadlock. Unfortunately, this deadlock often doesn't show up until a load test or, in the worst case, when your production application receives a lot of traffic. In this scenario, your WebLogic Server is running with a fixed number of threads. The application includes logic where a given request or action performs work in one thread and then blocks on work that must be done in another thread.
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