About

About.

Advertisements

Detail about the architecture of web sphere

Web Sphere is built on three main components they are
• Database
• J2EE application server
• A web server
The databases which it supports are
• DB2
• Oracle
• Cloudscape
Application server is IBMWAS and the supported web servers are
• IBM server
• Microsoft IIS
• Sun web server

Real time Websphere Application server Interview questions

1) What is the recommended free disk space in /tmp to install WAS.
1 GB
2) What is the default installation location of WAS in Linux.
Opt/IBM/WebSphere/AppServer
3) What is the default installation location of WAS in Sun Solaris.
Opt/IBM/WebSphere/AppServer
4) What is the default installation location of WAS in AIX
Usr/IBM/WebSphere/AppServer
 
5) List any 10 parameters in response file
-W silentInstallLicenseAcceptance.value=”true”
-P wasProductBean.installLocation=”C:\IBM\WebSphere\AppServer”
-OPT disableOSPrereqChecking=”true”
-OPT installType=”installNew”
-OPT createProfile=”true”
-OPT profileType=”deploymentManager”
-OPT PROF_enableAdminSecurity=”true”
-W nodehostandcellnamepanelInstallWizardBean.nodeName=”krishna_node”
-W nodehostandcellnamepanelInstallWizardBean.hostName=”localhost”
-W winservicepanelInstallWizardBean.winServiceQuery=”true”
-W winservicepanelInstallWizardBean.accountType=”localsystem”
-W winservicepanelInstallWizardBean.startupType=”manual”
 
6) Write the complete command to execute a response file.
<was-setup>./install –options “<absolute path of response file>” – silent
 
7) Which registry file will get updated after installation of WAS.
vpd.properties
 
8) What is the use of SOAP Connector port and what is the default soap port number for DMGR profile.
Client Applications like wsadmin uses Simple Object Access Protocol and that is   listening to the port 8879. If we want federate a profile by using SOAP protocol and SOAP connector port number, we can federate a profile.
 
9) What is the default Http transport port number for Application Server profile and what is the use.
9080, (if ssl was enabled 9443) If we want to invoke applications running on AppServer we are using HTTP transport port
 
10) What is the default Bootstrap port number in App.Serv profile and what is the use.
2809. To access the EJB’s, JNDI use bootstrap port to obtain initial context root.
 
11) Installation was successful and when I am trying to start server it is giving “Invocation Target Exception” why you will get this issue and how you are trouble shooting this issue.
May be the problem with hostnames, hostnames are mismatched. Add the host name in etc/hosts file which you had given at the time of installation.
 
12) What are different profile templates in WAS 6.0?
Dmgr, default and managed
 
13) Write the complete command to create an App.Serv profile through command line.
C:\IBM\WebSphere\AppServer\bin>wasprofile.bat -create -profileName AppSrv04 -profilePath“C:\IBM\WebSphere\AppServer\profiles\AppSrv04” -template Path“C:\IBM\WebSphere\AppServer\profileTemplates\default” -nodeName app_node04 -cellNamecell04 -hostName krishamurthy
 
14) Write a complete command to delete a profile.
C:\IBM\WebSphere\AppServer\profiles\AppSrv01\bin>wasprofile.bat -delete -profileName AppSrv01
 
15) If you get a problem before creating a log’s directory at the time of installation, at that time where you can check the status of installation
                   tmp/log.txt
 
16) What is the difference between managed node and unmanaged node
Manged Node contains node agent, we can administer federated profiles servers and applications from dmgr admin console. For unmanaged the will be no nodeagent.
 
17) What is the impact for the federated profile servers, if DMGR is down.
No impact on servers and applications
 
18) In which xml file, we can change the port numbers.
Serverindex.xml
 
19) What is a server.
Server provides a runtime environment for your web app’s Or Enterprise applications.
Server receives user request, process that request and execute that request and response will be generated to the end users.
 
20) If we stop the nodeagent, what will be the impact for end users.
There is no impact for end users
 
21) How to take backup with out stopping servers.
./backupConfig.sh –nostop
 
22) What are the different user registries under global security in 6.0 and 6.1.
Local OS, Custom, LDAP. Federated repository was added in 6.1
 
23) What is the necessity of global security?
To provide security for the admin console.
 
24) What is the port number for LDAP server with SSL and without SSL?
389 and 636
 
25) How to disable Global Security
./wsadmin.sh -conntype NONE
Securityoff    exit
 
26) How to know how many profiles are available.
/AppServer/bin>./wasprofile.sh –listProfiles
 
27) What are the advantages and disadvantages of Local OS,Custom and LDAP user registries?
Global Security: In 6.0 we have 3 ways to provide security for admin console.
          1) Local os user registry.
          2) Custom user registry.
          3) LDAP (Light Weight Directory Access Protocol) user registry.
a) Custom user registry: Here we have to create two files named:
          Users. Registry
          Groups. Registry
We can create this file any where but we have to configure this absolute path to the application servers.
b) LDAP: It is a mechanism & not a server. Here we are integrating seperate directory servers.
          if SSL is enabled the port number is 636, if it is not enabled 389.
          -> In local os user registry we have to create user accounts and that user accounts have to configure to websphere application servers.
          where as in the custom user registry specifying user names and passwords in a normal file and we are specifying the absolute path of that file into the websphere application server. whenever we are going for LDAP user registry we have to specify user id & password & type of directory server, port number (default is 389), if SSL is enabled we have to specify port number as 636 and we have to specify Base distinguished name which indicates authentication for users and we have to specify Bind distinguished name and Bind password which specify authorization for user and we have to select “Advanced Light Weight Directory Access Protocol user registry settings” there we have to specify user filter classes and group filter classes (automatically it will be there) and finally we have to restart the server.
 
28)What is the full form of JDBC.
JDBC (java Database Connectivity) is an API (Applicationprogram Interfaces), that is useful to write a java program to connect any database, and retrieve the data form the database and utilize the data in the java program.
Making a connection to a database
Creating SQL or MySQL statements
Executing that SQL or MySQL queries in the database
Viewing & Modifying the resulting records
We have 2 types of JDBC drivers in was. Those are  Type2(Thick) and Type4(Thin/Native    Protocol) jdbc drivers.Type2 JDBC drivers require the database client software on the client node to connect to the database server.Type4 JDBC drivers connect directly to the database server.
 
29) What is the full form of JAR and what a jar file contains?
An EJB module which contains enterprise java beans class files and EJB deployment descriptors are packed as JAR files with .jar extension.
 
30)Write the name of the jar file necessary to configure Oracle 9i & Oracle 10g Database.
In oracle 10g & 9i We have only one jar file i.e OJDBC14.JAR (for log) & Class12.jar (for 9i) and In DB2 we have 3 or more jar files. i.e DB2JCC.JAR,DB2JCC_LICENSE_C4.JAR, DB2JCC_LICENCE_CIS42.JAR.
-> The .jar file is nothing but a collection of .class files. It is necessary to communicate with the database. So we should configure this jar files with database.
 
31) What is a connection pool?
Connection pooling is a place where a set of connections are kept and are used by the different programmers with out creating connections to the database(it means there is a ready made connection available for the programmers where he can use). After using the connection he can send back that connection to the connection pool. Number of connections in connection pool may vary.
32) What is meant by Federation
33) What are the different types of console roles available and explain about each role?
 
34)  what is your goal and role in was?
Goal –
a. Goal is to provide infrastructure for the demands
b. goal is to provide stable environment
c. goal is to provide high availability
d. goal is to provide scalability
e. goal is to provide 0 downtime
Role-
a. involve in infrastructure architecting a.k.a design
b. involve in implementing architectures
c. involve in solving infrastructure issues
d. involve in solving application environment issues
e. involve in solving issues which become hurdles in providing high availability
f. involve in solving issues which become hurdles in scaling
 
35)  what is incident management?
Incident = Issue. Hurdle. Risk. Downtime. Security Breach.
Incident Management = Risk Plan. Potential incidents management.
 
36) Do you know how to configure ticketing tool with WAS?
This is a meaningless question. You need more information to address this question.
Ticketing System – is it part of IBM? Does it fall in Web Sphere Umbrella? Is it an application running on WAS? Is it a Web based app? or Java Client?
Unless you know these, it’s a blind question.
 
37) when you configure LDAP with application server, if the users are unable to connect to WAS. How do you trouble shoot this scenario?
You don’t trouble shoot, you *troubleshoot*
The issue is – U have LDAP, running on Server x. Server y, WAS bind to server x.
if a problem occurs, u need to dig like this –
A) Ldap up or not
B) If yes, can server y reach server x [simple ping or telnet on ldap port]
C) If yes – Ur infrastructure is clear
D) Any firewall between server y and server x. talk to firewall team, ask them to enable trace between server y and x. any droppage of packets?
E. if everything is clean, talk to ldap admin, enable trace on that specific group who are getting auth errors.
F) Look into systemout.log, find out what exactly the error message you get.
G) U have to login to admin console and verify the authentication. u can *test* ldap auth from console.  Feb 7 (2 days ago) Raju
 
38) What is the difference between Signed Certificate and Self-signed certificate? Which one you prefer?
 
39) In Windows 2003 box, an application server process is not responding. How do you trouble shoot this issue. Even when you are unable to kill the process.
*trouble shoot* – On any server, app server freeze – may because of resource crunch, or process failing to release a resource, jvm could not complete a specific thread, blablabla.
a. do u have enuf rights to kill the process?
b. check the processor utilization thru task manager
c. kill -3, if not responding, try again, again and again
d. verfiy the disk space.
e. verify error log and out log.
Blabla
 
40)  how many types of scripting you have done or you know?
such questions cannot be asked in a forum, or its difficult to answer. if i were you, i wud say, perl scripting, php, python, jython, tcl, jacl, ant, shell, blabla.  Feb 7 (2 days ago)
 
41) when you are on call support when you got a severity 1 ticket, how do you take action. Explain in detail.
Open the ticket, read the message what the problem is about.
login to targeted server(s), check logs, depending on error, propagate first hand info to stakeholders. sit on the issue, fix it, close it.
 
42) What is a fix pack, refresh pack and when you will go for fix pack installation and when you will go for refresh pack installation?
fix pack fixes certain issues.
refresh pack is a mile stone for a release.
a refresh pack takes you to a release, say
6.0.0.1 is a release. if you apply rp2, it becomes a release 6.0.2. if you apply fp35, it becomes 6.0.2.35, which is not a release.  Feb 7 (2 days ago)  Raju
 
43) when you find in a particular server ‘cpu starvation’ error message what you will do?
whenever there is not enough physical memory available to allow the high availability manager threads to have consistent runtimes. When the CPU is spending the majority of its time trying to load swapped-out processes while processing incoming work, thread starvation might occur.
Goto InfoCenter, search for starvation.
 
To achieve good performance and avoid receiving these error messages, it is recommended that you allocate at least 512 MB of RAM for each Java process running on a single machine.
 
High CPU usage in a large cell configuration when security is enabled
With certain configurations and states, the amount of time spent in discovery becomes substantial.
If a large the number of processes are defined within a core group, a proportionally large number of connections must be established to support these processes.
If a large number of inactive processes are defined within a core group, a proportionally large number of connections are attempted during each discovery interval.
If global security is enabled, the DCS connections are secured, and the impact of opening a connection greatly increases .
To decrease the CPU time spent in discovery:
In the administrative console, click Servers > Core groups > Core groups settings , and then select the -> DefaultCoreGroup.
Under Additional Properties, click Custom properties > New.
Enter IBM_CS_UNICAST_DISCOVERY_INTERVAL_SECS in the Name field and 120 in the Value field.
Click OK.
Then click New again and enter IBM_CS_SS_SECURE_TOKEN in the Name field andfalse in the Value field.
Click OK and then Save to apply these changes to the master configuration.
Restart the server for these changes to take effect.
Transient high availability heartbeat failures und 
11.If we said to analyze thread dumps can you do?
Ya!! Why not
 
44) How comfortable with scripting?
100% pakka comfortable 
 
45) Did you worked with JACL or Jython scripts?
I prefer one scripting style. Why wud I use two scripting styles? At a given point of time, scripting interface accepts only one language.
 
46) When you found hung thread error messages what you will do? Will you kill the process. If yes, in which case you have to kill the process?
Lucky you and lucky me, we have IBM’s InfoCenter. Is it not easy to perform a simple search on InfoCenter like this *hung thread*?
Configuring the hang detection policy
The hang detection option for WebSphere Application Server is turned on by default. You can configure a hang detection policy to accommodate your applications and environment so that potential hangs can be reported, providing earlier detection of failing servers. When a hung thread is detected, WebSphere Application Server notifies you so that you can troubleshoot the problem.
Add the following properties:
Name: com.ibm.websphere.threadmonitor.interval
Value: The frequency (in seconds)
Default: 180 seconds (three minutes).
Name: com.ibm.websphere.threadmonitor.threshold
Value: The length of time (in seconds).
Default: The default value is 600 seconds (ten minutes).
Name: com.ibm.websphere.threadmonitor.false.alarm.threshold
Value: The number of times (T) that false alarms can occur before automatically increasing the threshold.  Feb 7 (2 days ago)  Raju
 
47) Explain about your enivronment, servers, webservers, etc.,
Think about ur company and thier business. Cook a story. Serve it on the table with some masala, salt and pepper.
 
48) What is a document server and what is the use of it.
this is the funniest question one can ask.
what is a document server? in general a document server is a repository of documents in an enterprise.
what is the use of it? its the central repository and depending access polices agency wide authorized and authenticated *users* can access documents.
ex.,
u have prepared a document on ur environment. u need a place to put that document so that ur team can access it, ur manager can access it. above that, another team who wants to read that document can access that, above that, some infrastructure team can access it, above that datacom people can access it and so on.
what is the best place to put it?
on ur desk top? or attach to mail? or dump it in a shared location.
if its a shared location, what that could be? will you dump it in a zunkyard shared location or in a proper shared location? first  |  < previous  |  next >  |  last
  report spam reply
 
49) TYPES OF SEVERIATIES?
Severities will be of different types like Severity 1, 2, 3, 4, 5.
 Depending upon the type of issue it will be classified.
 
50) WHAT TYPE OF ISSUE’S CONTAIN SEVERIATY1 TICKET’S?
Severity 1 tickets are the most rare tickets which will get and
 which we have to get in our administration.
If our process is not running smooth, that means your application not responding,
 application server is not responding or entire environment falls then we will get
 severity 1 ticket.
 
51.WHAT IS THE DIFF B/W COREDUMP & THREAD DUMP?
there is not much difference between these two.
 In thread dump we can find, what are the active threads that are there at that
particular time. Where as core dump contains information about dead locks,
 hang threads also
 
52.WHEN THE SERVER HUNG HOW WILL IDENTIFY IN SYSOUT.LOG?
Its very simple in systemout.log we will find a particular thread is hung from this
many milli seconds will be found. The thread name will be WSVR****
 
53. HOW TO TAKE BACKUP THE APPLICATION?
Taking backup of the application can be done by using export option
in the admin console or directly from the directory location.
54. WHAT’S THE RELATION B/W WIILY INTROSCOPE & WAS(LIKE AGENT/AGENTLESS)?
Wily introscope is a third party tool which is used to monitor the server environments,
 not only WAS anything.

WebSphere Application Server Architecture

What is WAS
 
à Provides the infrastructure for running applications that run your business.
à Common environment and programming model for your applications.
àPlatform for developing and Deploying web services and SOA based apps
à Secure, Scalable, reliable transaction engine for ERP
à IBM WebSphere is architected to enable you to build business-critical applications for the Web
à WebSphere includes a wide range of products that help you develop and serve Web applications.
à They are designed to make it easier for clients to build, deploy, and manage dynamic Web sites more   productively
à WAS implements J2EE specification
 
WebSphere Application Server provides the environment to run your Web-enabled e-business applications. An application server functions as Web middleware or a middle tier in a three-tier e-business environment. The first tier is the HTTP server that handles requests from the browser client. The third tier is the business database (for example, DB2 UDB for iSeries) and the business logic (for example, traditional business applications, such as order processing). The middle tier is WebSphere Application Server, which provides a framework for a consistent and architected link between the HTTP requests and the business data and logic.
 
 
 
 
 
 
With the Base and Express packages, you are limited to single application server environments. The Network Deployment package allows you to extend this environment to include multiple application servers that are administered from a single point of control and can be clustered to provide scalability and high availability environments.
 
 
 
 
 
 
 
 
The typical application flow is as follows:
1. A Web client requests a URL in the browser (input page).
2. The request is routed to the Web server over the Internet.
3. The Web server immediately passes the request to the Web server plug-in.
All requests go to the Web server plug-in first.
4. The Web server plug-in examines the URL, verifies the list of host name
aliases from which it will accept traffic based on the virtual host information,
and chooses a server to handle the request.
5. A stream is created. A stream is a connection to the Web container. It is
possible to maintain a connection (stream) over a number of requests. The
Web container receives the request and, based on the URL, dispatches it to
the proper servlet.
6. If the servlet class is not loaded, the dynamic class loader loads the servlet
(servlet init(), then doGet() or doPost()).
7. JNDI is used for lookup of either datasources or EJBs required by the servlet.
8. Depending upon whether a datasource is specified or an EJB is requested,
the JNDI directs the servlet:
– To the corresponding database and gets a connection from its connection
pool in the case of a data source.
– To the corresponding EJB container, which then instantiates the EJB when
an EJB is requested.
9. If the EJB request involves an SQL transaction, it goes back to the JNDI to
look up the datasource.
10.The SQL statement is executed and the retrieved data is sent back either to
the servlet or to the EJB.
11.Data beans are created and handed off to JSPs in the case of EJBs.
12.The servlet sends data to JSPs.
13.The JSP generates the HTML that is sent back through the plug-in to the Web
server.
14.The Web server sends the output page (output HTML) to the browser.
 
 
Functionality of WAS
 
WebSphere Application Server supports asynchronous messaging through the use of a JMS provider and its related messaging system.(JMS 1.1 Messaging Provider)
 
WebSphere Application Server provides authentication and authorization capabilities to secure administrative functions and applications, using LDAP
 
WebSphere Application Server works with a Web server (such as the IBM HTTP Server) to route requests from browsers to the applications that run in WebSphere Application Server. Web server plug-ins are provided for installation with supported Web browsers. The plug-ins direct requests to the appropriate application server and perform workload balancing among servers in a cluster.
 
Web services enable businesses to connect applications to other business applications, deliver business functions to a broader set of clients and partners, interact with marketplaces more efficiently, and create new business models dynamically.
 
Delivers a high performance and extremely scalable transaction engine for dynamic e-business applications
 
Packaging
 
WebSphere Application Server is available in multiple packaging options.
 
WebSphere Application Server – Express V6.0
 
à Single Server environment.(No Clustering or multi server management)
à J2EE 1.4 support
àMedium-sized business
àContains Rational Web Developer application tool
à Doesn’t handle EJB and JCA
à Limited to 2 CPU’s
 
WebSphere Application Server V6.1 (Base)
 
àSlightly differs in packaging and licensing
à Contains Application Server toolkit
à Includes a trial version of Rational Application Developer
àUnlimited CPU’s
 
WebSphere Application Server Network Deployment V6
 
àExtends Base version
àClustering capabilities
àEdge Components which provide high performance and availability (Caching Proxy and Load Balancer)
àHA for distributed configurations
àLarge Enterprise applications
àScalability, Availability and Performance
àWeb Server plug-in supports weighted WLM
 
 
 
àAll V6 application servers have the same core and base functionality
àWebSphere Application Server – Express V6 node can be upgraded to a WebSphere Application Server V6 node(.Can be done without any software upgrades .Only a paper license upgrade is required)
àWebSphere Application Server- Express V6 and WebSphere Application Server V6 node can be federated into a WebSphere Application Server – Network Deployment V6 cell (Can be done without any software upgrades .Only a paper license upgrade is required)
 
 
Differences b/n WAS Version
 
WAS 5: J2EE 1.2/1.3 support
               JDK 1.3 support
                Web Services based on Apache engine
               
 
WAS 6.0: J2EE 1.2/1.3/1.4 support
                   JDK 1.4 support (JDK 1.4.2)
                   Web Services based on J2EE 1.4
                    High Availability Manager
                    Java Based Messaging Engine
                    EJB 2.1, JMS 1.1, JCA 1.5, Servlet 2.4, and JSP 2.0
                    Supports Java Server Faces (JSF)
                    Creates Archive of the existing WAS configurations and the archive can be          
                    used to create new configurations. 
                    Profiles and all profiles use same WebSphere binaries(Less storage)
                    Node groups
                    Service integration functionality provides both message-oriented and service      
                    Oriented applications 
 
WAS 6.1: J2EE 1.2/1.3/1.4 support
                    JDK 5.0 support
                    JSF-a framework for Web applications  
                    Integrated Console
                    Security changes
                    Secure and Scalable runtime 
 
Edge Components
 
Using Edge components can reduce Web server congestion, increase content availability, and improve Web server performance. As the name indicates, Edge components usually run on machines that are close (in a network configuration sense) to the boundary between an enterprise’s intranet and the Internet.
 
Web container
àA Web container, which processes HTTP requests, servlets, and JavaServer Pages (JSPs)
 
à Web container transport chains:
Requests are directed to the Web container using the Web container inbound transport chain. The chain consists of a TCP inbound channel that provides the connection to the network, an HTTP inbound channel that serves HTTP 1.0 and 1.1 requests, and a Web container channel over which requests for servlets and JSPs are sent to the Web container for processing
 
à Servlet processing
When handling servlets, the Web container creates a request object and a response object, then invokes the servlet service method. The Web container invokes the servlet’s destroy method when appropriate and unloads the servlet, after which the JVM performs garbage collection.
 
à HTML and other static content processing
Requests for HTML and other static content that are directed to the Web container are served by the Web container inbound chain. However, in most cases, using an external Web server and Web server plug-in as a front-end to a Web container is more appropriate for a production environment.
_
àSession management
Support is provided for the javax.servlet.http.HttpSession interface as described in the Servlet application program interface (API) specification.
_
à Web services engine
Web services are provided as a set of APIs in cooperation with the J2EE applications. Web services engines are provided to support Simple Object Access Protocol (SOAP).
 
EJB Container
 
àThe Enterprise JavaBeans (EJB) container provides all the runtime services that are needed to deploy and manage enterprise beans. It is a server process that handles requests for both session and entity beans.
 
àThe enterprise beans, packaged in EJB modules, installed in an application server do not communicate directly with the server. Instead, the EJB container provides an interface between the enterprise beans and the server. Together, the container and the server provide the enterprise bean runtime environment.
 
àThe container provides many low-level services, including threading and transaction support. From an administrative viewpoint, the container manages data storage and retrieval for the contained enterprise beans. A single container can host more than one EJB Java archive (JAR) file.
 
WAS Services
J2EE Connector Architecture services
Transaction service
Dynamic cache service
Message listener service
Object Request Broker service
Administrative service (Java Management Extensions)
Diagnostic trace service
Debugging service
Name service (Java Naming Directory Interface)
Performance Monitoring Interface service
Security service (JAAS and Java 2 security)
Service Integration Bus service
The Web server:
A Web server handles the HTTP protocol. When the Web server receives an HTTP request, it responds with an HTTP response, such as sending back an HTML page. To process a request, a Web server may respond with a static HTML page or image, send a redirect, or delegate the dynamic response generation to some other program such as CGI scripts, JSPs (JavaServer Pages), servlets, ASPs (Active Server Pages), server-side JavaScripts, or some other server-side technology. Whatever their purpose, such server-side programs generate a response, most often in HTML, for viewing in a Web browser.
Understand that a Web server’s delegation model is fairly simple. When a request comes into the Web server, the Web server simply passes the request to the program best able to handle it. The Web server doesn’t provide any functionality beyond simply providing an environment in which the server-side program can execute and pass back the generated responses. The server-side program usually provides for itself such functions as transaction processing, database connectivity, and messaging.
While a Web server may not itself support transactions or database connection pooling, it may employ various strategies for fault tolerance and scalability such as load balancing, caching, and clustering—features oftentimes erroneously assigned as features reserved only for application servers.
Eg: Apache HTTP Server, Sun ONE Web Server, iPlanet Web Server
The application server:
As for the application server, according to our definition, an application server exposes business logic to client applications through various protocols, possibly including HTTP. While a Web server mainly deals with sending HTML for display in a Web browser, an application server provides access to business logic for use by client application programs. The application program can use this logic just as it would call a method on an object (or a function in the procedural world).
Such application server clients can include GUIs (graphical user interface) running on a PC, a Web server, or even other application servers. The information traveling back and forth between an application server and its client is not restricted to simple display markup. Instead, the information is program logic. Since the logic takes the form of data and method calls and not static HTML, the client can employ the exposed business logic however it wants.
In most cases, the server exposes this business logic through a component API, such as the EJB (Enterprise JavaBean) component model found on J2EE (Java 2 Platform, Enterprise Edition) application servers. Moreover, the application server manages its own resources. Such gate-keeping duties include security, transaction processing, resource pooling, and messaging.
Like a Web server, an application server may also employ various scalability and fault-tolerance techniques.
Difference between AppServer and a Web server :
(1) Webserver serves pages for viewing in web browser, application server provides exposes businness logic for client applications through various protocols
(2) Webserver exclusively handles http requests.application server serves bussiness logic to application programs through any number of protocols.
(3) Webserver delegation model is fairly simple,when the request comes into the webserver,it simply passes the request to the program best able to handle it(Server side program). It may not support transactions and database connection pooling.
(4) Application server is more capable of dynamic behaviour than webserver. We can also configure application server to work as a webserver.Simply applic! ation server is a superset of webserver.
 
In J2EE application modules are packaged as EAR, JAR and WAR based on their functionality .These files are simply zipped files using java jar tool. These files are created for different purposes.
.jar files:
JAR files (Java ARchive) allows aggregating many files into one, it is usually used to hold Java classes in a library. i.e. Math.jar These files are with the .jar extension. The .jar files contain the libraries, resources and accessories files like property files.
.war files: 
WAR files (Web Application aRchive) stores XML, java classes, and JavaServer pages for Web Application purposes. These files are with the .war extension. The war file contains the web application that can be deployed on the any servlet/jsp container. The .war file contains jsp, html, javascript and other files for necessary for the development of web applications.
.ear files:

EAR files (Enterprise ARchive) combines JAR and WAR files to make a combined archive for Enterprise Applications. The .ear file contains the EJB modules of the applications

WebSphere Application Server Training Course Content

1.      WebSphere Product Family Overview

·         J2EE 1.4 platform Architecture

·         WebSphere Software platform

·         About Application Server

·         WebSphere V6.1 packaging

·         Product Offerings (Express, Base & ND)

·         IBM HTTP Server

2.     Stand-Alone Architecture Overview

·         Application Server Basics

·         Rum Time Architecture

·         JDBC Providers

·         Data Sources 

·         Architecture Administration

·         WebSphere Profiles Overview   

·         WebSphere profiles Benefits 

·         Managing Profile

·          

3.     Network Deployment Architecture

·         Overview

·         Network Deployment Basics       

·         Network Deployment Runtime Flow

·         Managed vs Unmanaged Nodes

·         Network Deployment Administration Flow

·         File Synchronization

·         Network Deployment Profiles

·         Managing Web Servers  

·         Managing plug-in

·         Webserver  Custom plugin-cfg.xml

·         Managing Webserver  Plug-in properties

·         Messaging overview

·         High Availability

·         Data Replication

·         Node Groups

·         Name Service Overview

·         Configuration of virtual hosts

 

1.      Application Server Installation

·         Installation Overview

·         Installation Environments

·         Requirements Specification

·         Profile Creation

·         Profile Management Tool

·         Manage profiles Command Line Tool

·         First Steps

·         Installation Verification

·         Silent Installation

·         Uninstallation

·         Sample Applications during Installations

·         Directory Structure

·         Common Command Line Tools

·         Server Commands

·         Web server Installation 

·         Web server Plug-in installation   

 

 

2.     Administrative Console

·         Starting Administrative Console

·         Administrative Console in a Cell Topology

·         Administrative Console Login

·         Administrative Console Areas

·         Administrative Console Navigation Tree

·         Administrative Console Help

·         Administrative Console Preference

·         Administrative Console Filters

·         Trouble Shooting Information

·         Tivoli Performance Viewer

3.      J2EE Overview

·         Application Programming Model

·         J2EE Benefits

·         Standards Supported

·         J2EE 1.4 Platform Architecture

·         J2EE Application Components

·         J2EE Packaging Files

 

4.     Application Installation

·         Creating J2C Authentication Alias

·         Creating JDBC Provider for Resources

·         Creating Data Sources

·         Deployment

·         Managing Applications

·         Starting an Application

·         Application Configuration Options

·         Application Update

·         Export Application

·         Export DDL

 

5.     Clusters

·         What is WLM?

·         Introduction to Clusters

·         Types of Clusters

·         Creating Clusters

·         Installing Application to a Cluster

·         Controlling Cluster

·         Request Routing

·         Failover

·         Session Management

·         Session Affinity

·         Session Persistence

·         Replication Domains

6.     WebSphere  Platform Messaging

·         Introduction to Messaging

·         JMS

·         Service Integration Bus

·         Adding Bus Members

·         Messaging Engine

·         Data stores

·         Bus Destinations

·         JMS Connection Factories

·         JMS Destinations

·         JMS Activation Specifications

·         High Availability

·         Quality of Service for Reliability

·         Relationship to WebSphere MQ

7.     WebSphere  Security

·         Basic Security Model

·         WebSphere  Security  Overview

·         Authentication and Access Control

·         Registries and Authentication Types

·         Application Security (J2EE Security)

·         Federated Repositories

·         Custom Registry Configuration

·         Local operating System Security

·         Authentication Mechanisms

·         LTPA and LDAP

·         Single Sign-On (SSO)

·         Administrative Security Roles

·         Java Security Model

·         Java2 Security Overview

·         SSL

·         Certificates and Key Management

8.     Performance Monitoring

·         Performance Issues

·         Need for Performance Tuning

·         WebSphere Performance Tuning

·         PMI Data Collection

·         PMI Data Models  and Counters

·         Enabling PMI

·         Tivoli Performance Viewer

·         Tivoli Performance Viewer Interface

·         Tivoli Performance Viewer Modules

·         Request Metrics Overview

·         Request Metrics Features

·         Performance Advisors

·         Using TPV Performance Advisor

·         Configuring External Monitoring Tool

9.     Problem Determination

·         Installation Log files

·         Server Log files

·         Viewing logs

·         Configure JVM Logs

·         Viewing runtime messages in console

·         HTTP plug-in logs

·         Embedded Http Server Logs 

·         Trace, Enable Trace

·         Setting Log detail Levels

·         Generating IBM Heap Dump

·         Generating Thread Dump

·         Hung Thread  Defecation

·         Problem Determination Tools

·         Collector Tools

·         Plug-in Analyzer

·         Heap Analyzer

·         Thread Analyzer

·         GC Analyzer

10. WS ADMIN and Scripting

·         Comparison B/W Console and wsadmin

·         Why Scripting

·         Introduction to Wsadmin

·         Overview of Wsadmin

·         Administrative Objects in Wsadmin

·         Invoking Wsadmin

·         Invoking Wsadmin  with Security Enabled

·         Connection Type in Wsadmin

·         Introduction  to Scripting

·         Executing Scripts

·         Help for Commands

11.   Runtime Functions

·         Class Loaders Over view

·         Delegation Model

·         Class Loader Hierarchy

·         Shared Libraries

·         Creating a Library

·         Applying a Library

12.  Migrations & Patching

·         Applying Fixes

·         Migration  From V6.0 to V6.1

·         WebSphere profiles Benefits

·         Managing  Profiles