Thread Dumps in WebLogic12c Server

Here going to provide information about different ways on taking java thread dumps in a WebLogic Server environment.

Thread dumps are very useful to analyze and troubleshoot performance related issues such as server hang, deadlocks, slow running, idle or stuck applications,  etc.

Different ways to take thread dumps in WebLogic Server

Always prefer Operating system(OS) commands rather instead of Admin Console or Java Classes, because if the console is hanging, users won't be able to connect to it to issue thread dumps.

1. OS Commands for Thread Dumps

i) On Windows,

<ctrl>+<break> -- the thread dumps are generated in the server stdout

ii) On Solaris / Linux

first identify the process ID (pid) using   ps -ef | grep java, then run   kill -3 <pid> td_filename 2>&1

2. Using weblogic.WLST ( work only from WLS 9.x onwards)


First set CLASSPATH using setDomain.cmd or setDomain.sh (wlst.sh /wlst.cmd will also do in path C:\Oracle\Middleware\wlserver_12.1\common\bin ). Then run below command

java weblogic.WLST ThreadDumps.py

save below code in ThreadDumps.py file:
connect("<username>","<password>","t3://<url>:<port>")
cd(‘Servers’)
cd(‘AdminServer’)
threadDump()
disconnect()
exit()
threadDump()

The thread dumps get stored in the location from where you run it.

3. From Weblogic Administration Console

navigating to Server -> <server_name> -> Monitoring -> Dump threads stack.

4. From the JRockit Command line

jrcmd <pid> print_threads

Disabling and enabling the Weblogic 12c Administration Console

To disable:

1. Select your domain name in the Domain Structure panel of the console(as base_domain below).



     2. Select Configuration | General, and click Advanced at the bottom of the page, and unselect Console Enabled.

OR

Using WLST:-

connect("username","password")
edit()
startEdit()
cmo.setConsoleEnabled(false)
save()
activate()
disconnect()
exit()

3. To enable, you can use WLST. The following code shows how to do it:

connect("username","password")
edit()
startEdit()
cmo.setConsoleEnabled(true)
save()
activate()
disconnect()
exit()

 

Weblogic 12c Installation Directories Structure

Exploring Middleware Home Directory

By default, Weblogic 12c choose C:\Oracle\Middleware directory for installation on Windows.

Oracle\Middleware Directory

Directory	Contents
/ coherence_3.7	Coherence home directory
/ jdk160_29	Sun JDK ((Recommended for Development Mode))
/ jrockit_version	JRockit JDK (Recommended for Production Mode)
/ logs	Location for various log files about installation and uninstallation for the Middleware home directory.
/modules	Location for modules such as Apache Ant
/ oepe_12.1.1.0.1	Files related to Oracle Enterprise Package for Eclipse
/ patch_ocp371
/ patch_oepe101
/user_projects	Contains Domain
/ utils	contains utilities that are used to support the installation of all products installed in this home directory.
/ wlserver_12.1	WebLogic Server home directory
.home	This file contains the information about the Middleware home directory.
domain-registry.xml	This registry file contains the location of all domains currently registered with this WebLogic Server installation. Whenever you add a new domain, it is registered in this file.
ocm.rsp	This response file contains information about the Oracle Configuration Manager (OCM) installation.
registry.dat	This registry contains product-related information, such as version number, patch set level, patch level, and location of the product installation directories. It also contains the name of the installed JDK(s) and the Java home.
registry.xml	This is an encrypted version of the registry.xml file.

WebLogic Server Home Directory(WL_HOME): By default it is located in the Oracle\Middleware\wlserver_12.1



WebLogic Server Domain Directory

Directory	Content
/ autodeploy	In a development environment, the server will automatically deploy any applications or modules you place here. You must run the server in development mode for it to take advantage of the automatic deployment feature.
/ bin	Contains the start and stop scripts
/ config	Contains the key domain configuration file, config.xml.
/ console-ext	Contains any Administration Console extensions you've created
/ init-info	This directory contains files that are used for WebLogic domain provisioning. You should not modify any files in this directory.
/ lib	You can place JAR files in this directory so they can be available to all applications running on the domain's server instances.
/ security	Holds security-related files such as SerializedSystemIni.dat.
/ servers	This is an important directory that contains a separate subdirectory for each of the servers in your domain, including both Admin and Managed Servers.
fileRealm.properties
startWebLogic.cmd
startWebLogic.sh

Note:

Note while creating  the Middleware home directory:

• Do not include spaces in the name of your Middleware home directory otherwise the CLASSPATH may not be resolved properly.


•  You can install only one instance of each version of a WebLogic Server product in a single Middleware home directory. For example, you can install only one instance of the current version of WebLogic Server in a Middleware home directory, but you can have an earlier version of WebLogic Server in a separate Middleware home directory.


• If the home directory is not empty and it does not contain registry.xml, or if any of the product installation directories are not empty, one of the following messages is displayed:

For home directory selection task—Middleware home directory is not empty. Proceed with installation?

For product installation directory selection task—One or more installation directories are not empty. Proceed with installation?

 

JAVA Enterprise Edition 6.0 - JEE6

List of Technologies that are included in Java Enterprise Edition 6.0 ( JEE6 ) release .

Web Services Technologies:
Java API for RESTful Web Services (JAX-RS) 1.1	JSR 311
Implementing Enterprise Web Services 1.3	JSR 109
Java API for XML-Based Web Services (JAX-WS) 2.2	JSR 224
Java Architecture for XML Binding (JAXB) 2.2	JSR 222
Web Services Metadata for the Java Platform	JSR 181
Java API for XML-Based RPC (JAX-RPC) 1.1	JSR 101
Java APIs for XML Messaging 1.3	JSR 67
Java API for XML Registries (JAXR) 1.0	JSR 93
Web Application Technologies:
Java Servlet 3.0	JSR 315
JavaServer Faces 2.0	JSR 314
JavaServer Pages 2.2/Expression Language 2.2	JSR 245
Standard Tag Library for JavaServer Pages (JSTL) 1.2	JSR 52
Debugging Support for Other Languages 1.0	JSR 45
Enterprise Application Technologies:
Contexts and Dependency Injection for Java (Web Beans 1.0)	JSR 299
Dependency Injection for Java 1.0	JSR 330
Bean Validation 1.0	JSR 303
Enterprise JavaBeans 3.1 (includes Interceptors 1.1)	JSR 318
Java EE Connector Architecture 1.6	JSR 322
Java Persistence 2.0	JSR 317
Common Annotations for the Java Platform 1.1	JSR 250
Java Message Service API 1.1	JSR 914
Java Transaction API (JTA) 1.1	JSR 907
JavaMail 1.4	JSR 919
Management and Security Technologies:
Java Authentication Service Provider Interface for Containers	JSR 196
Java Authorization Contract for Containers 1.3	JSR 115
Java EE Application Deployment 1.2	JSR 88
J2EE Management 1.1	JSR 77
Java EE-related Specs in Java SE
Java API for XML Processing (JAXP) 1.3	JSR 206
Java Database Connectivity 4.0	JSR 221
Java Management Extensions (JMX) 2.0	JSR 255
JavaBeans Activation Framework (JAF) 1.1	JSR 925
Streaming API for XML (StAX) 1.0	JSR 173

 Read more for the application servers supporting JEE6

Application Servers Which Support JEE6 Specifications 

 

Oracle WebLogic Server Version 12.1.1 . 

This version of Oracle Weblogic Server is also Known as Weblogic 12c Release 1 .

Check this link for more details on JEE6 Specifications supported by Weblogic Server 12c Release 1.

Weblogic Server 12c Release 1 Download. 

 

JBoss Application Server 7 :

JBoss Application Server 7 is the latest release in JBoss Application Server Release.

For Downloading , and Supporting Specifications and Start Up Guide :  

 

IBM WebSphere Application Server V8 :

This was the first application Server that was released with JEE6 Support.

For Downloading WebSphere Application Server V8.5 :

 

Oracle GlassFish Open Source Edition 3.1.2 . 

For Downloading GlassFish Server :

 

Error With Apache 2.4 on Windows 7 64 bit

I was trying to install Apache Http Server 2.4 on Windows 7 64 bit and was receiving error while starting the Apache Server :

 

AH00558: httpd.exe: Could not reliably determine the server's fully qualified domain name, using XXXX::XXXX:XXXX:XXXX.
Set the 'ServerName' directive globally to suppress this message

 

Root Cause :

Apache Server is looking for the hostname name which it can use to start and listen for request. If there is a hostname configured on the machine and it is not configured in the httpd.conf file then it will throw this error .

Solution:

• Get the hostname of the machine on which the Apache Server is installed using the OS command : hostname


• Configure the same in the httpd.conf file with the directive : ServerName as shown below:

ServerName Sandeep

• Restart the Apache Server.

In case you do not want to use the Machine Hostname with the Apache Server then make the ServerName Entry in the httpd.conf file as localhost.

 

 

Different Memory Argument values for SOA Servers and BAM Servers In Weblogic 11g.

This post is about providing specific memory arguments values to SOA server and BAM servers in Weblogic 11g.

There are two scenarios:

1. 
   

   Admin Server is Started using the startWeblogic.cmd or startWeblogic.sh file and all other servers are started using startManagedWeblogic.cmd or startManagedWeblogic.sh 

   
   


2. 
   

   Admin Server is Started using the startWeblogic.cmd or startWeblogic.sh file and all other servers are started using the Admin Server Console.

   
   

Case1 :  

Admin Server is Started using the startWeblogic.cmd or startWeblogic.sh file and all other servers are started using startManagedWeblogic.cmd or startManagedWeblogic.sh 

First of all we have to analyse the startWeblogic.sh file that is used to start the Admin Server and the startManagedWeblogic.sh file that is used to start all other managed servers such as SOA server and BAM server.

Both the above mentioned file uses setDomainEnv.sh file to set the Domain related environment.

And setDomainEnv.sh file uses setSOADomainEnv.sh file for setting SOA specific environments.

So the memory related arguments like Xmx and Xms are picked up from the file : setSoaDomainEnv.sh file present in the $DomainHome/bin directory.

So, in order to provide different Xmx and Xms values for Admin Server , SOA server and BAM server we have to modify the setSOADomainEnv.sh file as shown below :

Imp : Please make sure to take backup of all the original files before modifying them .

In setSOADomainEnv.sh file comment the below lines :

# DEFAULT_MEM_ARGS="-Xms2048m -Xmx2048m"
# PORT_MEM_ARGS="-Xms2048m -Xmx2048m"

Insert the below lines replace the above commented code :

# line to specify different Xmx and Xms values to soa_server and bam_server.

if [ "${SERVER_NAME}" = "soa_server1" ] || [ "${SERVER_NAME}" = "soa_server2" ]; then
DEFAULT_MEM_ARGS="-Xms2048m -Xmx2048m"
PORT_MEM_ARGS="-Xms2048m -Xmx2048m"
elif [ "${SERVER_NAME}" = "bam_server1" ] || [ "${SERVER_NAME}" = "bam_server2" ]; then
DEFAULT_MEM_ARGS="-Xms2048m -Xmx2048m"
PORT_MEM_ARGS="-Xms2048m -Xmx2048m"
elif [ "${SERVER_NAME}" = "" ] || [ "${SERVER_NAME}" = "AdminServer" ]; then
DEFAULT_MEM_ARGS="-Xms2048m -Xmx2048m"
PORT_MEM_ARGS="-Xms2048m -Xmx2048m"
else
DEFAULT_MEM_ARGS="-Xms2048m -Xmx2048m"
PORT_MEM_ARGS="-Xms2048m -Xmx2048m"
fi

# end of code

 

Case 2 :  

Admin Server is Started using the startWeblogic.cmd or startWeblogic.sh file and all other servers are started using the Admin Server Console.

In this case, the Memory Arguments can be provided to from the Admin Server Console using the below steps :

 

•  Login into the Weblogic Administration Console using URL : http://admin_server_hostname:port/console


• Expand Environment Tree available on the left hand panel of the Admin Console.


• Click on Servers .


• For each Server say ( soa_server1 , and bam_server ) click on the server name .


• Then click on the Configuration tab.


• Then go to the Server Start tab available on the top of the page.


• Add the memory values in the Arguments field as shown below. There is no need to use newline. You can provide as many memory options as you want in this area and all the options will be separated by one white space character only.

 

-Xmx2048m -Xms2048m

• Click Save

Post you may be Interested: 

Click If want to learn how to start Managed Servers using Node Manager and Admin Console then you can follow the below link :




If you are facing any issues with the Node Manager then you can see some debug steps in the below link :

 

 

 

Starting Managed Servers without an Administration Server using Node Manager and WLST

Weblogic 12c

 

The steps for starting the Managed  Server without AdminServer using WLST and Node Manager are as follows :

i)  Setting up your environment.

Add WebLogic Server classes to the CLASSPATH environment variable and WL_HOME\server\bin to the PATH environment variable.  OR

You can use a  C:\Oracle\Middleware\wlserver_12.1\server\bin\setWLSEnv.cmd  script to set both variables.



 

ii)  Start WLST Session using command : java weblogic.WLST



iii)  Start Node Manager using command :

                         startNodeManager(verbose='true', NodeManagerHome='C:\\Oracle\\Middleware\\wlserver_12.1\\common\\nodemanager', ListenPort='5556', ListenAddress='localhost')





iv) Connect WLST to a Node Manager by entering the nmConnect command.

nmConnect('weblogic', 'weblogic123', 'localhost', '5556', 'base_domain' , 'C:\\Oracle\\Middleware\\user_projects\\domains\\base_domain' , 'ssl')



note: Node Manager security relies on a one-way SSL connection between the client and server.If you are establishing a command line connection to the Java Node Manager using the WebLogic Server Scripting Tool (WLST) nmConnect command, you provide the Node Manager user name and password(here weblogic and weblogic123 respectively). Node Manager verifies the username and password against the domain's nm_password.properties file.Node Manager credentials are located on the Security>General>Advanced Options of Console page.Administration Console users do not need to explicitly provide credentials to connect to Node Manager—the Node Manager user name and password are available in the domain configuration and are provided automatically.

v) Starts the managed server in the current domain using Node Manager. : nmStart('Server-0')



 

 

 Related Common Issues :

 

If you are trying to automate the environment using Node Manager and WLST .

And you are trying to Start the Admin Server and all the Managed Server using WLST only.

And the Managed servers are to be started for the first time using WLST and Node Manager then you may encounter the below error :

 

    
    
    
   
There are 1 nested errors:

weblogic.management.ManagementException: Booting as admin server, but servername, soa_server1, does not match the admin server name, AdminServer
at weblogic.management.provider.internal.RuntimeAccessService.start(RuntimeAccessService.java:67)
at weblogic.t3.srvr.ServerServicesManager.startService(ServerServicesManager.java:461)
at weblogic.t3.srvr.ServerServicesManager.startInStandbyState(ServerServicesManager.java:166)
at weblogic.t3.srvr.T3Srvr.initializeStandby(T3Srvr.java:879)
at weblogic.t3.srvr.T3Srvr.startup(T3Srvr.java:566)
at weblogic.t3.srvr.T3Srvr.run(T3Srvr.java:467)
at weblogic.Server.main(Server.java:71)

Cause :

The reason for the above error is that when the Managed Server are to be started for the first time using the Node Manager and WLST,  the boot.properties file ( at %domain_home%/servers/ManagedServer/security/) and startup.properties file ( %domain_home%/servers/ManagedServer/data/NodeManager/) should be already present.

Solution :

To generate the boot.properties file , and startup.properties file use the below WLST command :

 nmGenBootStartupProps('ms1')