Clustering

There are two methods of clustering

                Horizontal Clustering

                Vertical Clustering

Horizontal Clustering:

Horizontal scaling involves running multiple Java application servers (JVM) on two or more separate physical hardware’s (machines). When you scale horizontally, you add additional hardware that hosts additional JVM to the cluster.

Vertical Clustering:

Vertical scaling involves multiple Java application servers (JVM) running on a single physical machine. When you scale vertically, you join additional JVM to the cluster by adding to the same physical machine, which is limited by the limitation of the same physical machine.

Disabling and Enabling Admin Console

Many at times for most of our administration work including the changes (deployments, start/stop of servers, etc) or configurations (JMS, creation/deletion/editing of our servers, etc) we use our weblogic admin console.

But, for security reasons some of the banking companies for its core banking applications prefer to disable the admin console in its banking applications.

This short and sweet article mainly targets to present you on how to enable and disable your admin console:

Disabling your Admin Console:

We can disable our weblogic admin console in two different ways

1)      Admin console

2)      Weblogic Scripting Tool

From Admin console:-

To disable access to the Administration Console:

1. After you log in to admin console click Lock & Edit.
2. In the left pane of the Console, under Domain Structure, select the domain name.
3. Select Configuration > General, and click Advanced at the bottom of the page.
4. Deselect Console Enabled.
5. Click Save.
6. To activate these changes, click Activate Changes.

From WLST:-

connect(“weblogic“,”weblogic“,”t3://localhost:7001“)

edit()

startEdit()

cmo.setConsoleEnabled(false)

save()

activate()

disconnect()

exit()

Enabling the Admin Console:

After we disable the admin console we can enable it again by using WLST.

Following are the steps on the same:

connect(“weblogic“,”weblogic“,”t3://localhost:7001“)

edit()

startEdit()

cmo.setConsoleEnabled(true)

save()

activate()

disconnect()

exit()

Note: Here,

1)      weblogic and weblogic are the user id and password of admin console.

2)      t3://localhost:7001 is the admin console URL

3)      After we enable/disable the admin console RESTART your admin server

WebLogic Tutorials

WebLogic Server Administration

WebLogic Server:

Oracle WebLogic is a server software application that runs on a middle tier, between back-end databases and related applications an browser-based thin clients. WebLogic is a leading e-commerce online transaction processing (OLTP) platform, developed to connect users in a distributed computing environment and to facilitate the integration of mainframe applications with distributed corporate data and applications.

WebLogic server is based on Java2 Platform, Enterprise Edition (J2EE), the standard platform used to create Java-based multi-tier enterprise applications.

Oracle WebLogic Server 12c is the industry's best application server for building and deploying enterprise Java EE applications with support for new features for lowering cost of operations, improving performance, enhancing scalability and supporting the Oracle Applications portfolio.

WebLogic Versions:

WebLogic Server 12c (12.1.1) - March 2012

 WebLogic Server 12c (12.0) - December 1, 2011

 WebLogic Server 11gR1 PS5 (10.3.6) - February 2012

WebLogic Server 11gR1 PS4 (10.3.5) - May 16, 2011

WebLogic Server 11gR1 PS3 (10.3.4) - January 15, 2011

WebLogic Server 11gR1 PS2 (10.3.3) - April 2010

WebLogic Server 11gR1 PS1 (10.3.2) - November 2009

WebLogic Server 11g (10.3.1) - July 2009

WebLogic Server 10.3 - August 2008

WebLogic Server 10.0 - March 2007

WebLogic Server 9.2

WebLogic Server 9.1

WebLogic Server 9.0 - November 2006

WebLogic Server 8.1 - July 2003

WebLogic Server 7.0 - June 2002

WebLogic Server 6.1

WebLogic Server 6.0 - file date March 2001 on an old CD

WebLogic Server 5.1 (code name: Denali) First version supporting hot deployment for applications (via command line)

WebLogic Server 4.0


Domain: The basic administrative unit for a WebLogic Server installation is called a domain. A domain is a logically related group of WebLogic Server resources that you manage as a unit. A domain always includes only one instance of WebLogic Server called the Administration Server. The Administration Server serves as a central point of contact for server instances and system administration tools. A domain may also include additional WebLogic Server instances called Managed Servers.
You can configure some or all of these Managed Servers to be part of a WebLogic Server cluster. A cluster is a group of WebLogic Server instances that work together to provide scalability and high-availability for applications. A Managed Server in a cluster can act as a backup for services such as JMS and JTA that are hosted on another server instance in the cluster. Your applications are also deployed and managed as part of a domain.

Node Manager: Node Manager is a Java program provided with WebLogic Server that enables you to start, shut down, restart, and monitor remote WebLogic Server instances. To enable these capabilities, you run an instance of Node Manager on each physical machine in your domain.
A Node Manager process is not associated with a specific WebLogic domain but with a machine. You can use the same Node Manager process to control server instances in any WebLogic Server domain, as long as the server instances reside on the same machine as the Node Manager process. Node Manager must run on each computer that hosts WebLogic Server instances—whether Administration Server or Managed Server—that you want to control with Node Manager.

WebLogic Server provides two versions of Node Manager, Java-based and script-based, with similar functionality. However, each version has different configuration and security considerations.

Java-based Node Manager: Java-based Node Manager runs within a Java Virtual Machine (JVM) process. It is recommended that you run it as a Windows service on Windows platforms and as an operating system service on UNIX platforms, allowing it to restart automatically when the system is rebooted.

Oracle provides native Node Manager Libraries for Windows, Solaris, HP UX, Linux on Intel, Linux on Z-Series, and AIX operating systems.

Note: Node Manager is not supported on Open VMS,OS/390,AS400,UnixWare/Tru64 UNIX.

Script-based Node Manager: For UNIX and Linux systems, WebLogic Server provides a script-based version of Node Manager. This script is based on UNIX shell scripts, but uses SSH for increased security. SSH uses user-id based security. For information on configuring the script version of Node Manager.

See more details about Node Manager Configuration and Properties

Note: It is recommended that you run script-based Node Manager as Operating System services, which allows to restart automatically when the system is rebooted.This version does not provide as much security as the Java-based version. However, the advantage of the script-based Node Manager is that it can remotely manage servers over a network that has been configured to use SSH. No additional server installation is required. The scripts merely have to be copied to the remote machine.



Administration Server: Admin Server is an instance of Weblogic server. The Administration Server operates as the central control entity for the configuration of the entire domain. It maintains the domain's configuration documents and distributes changes in the configuration documents to Managed Servers. You can also use the Administration Server as a central location from which to monitor all resources in a domain.

Managed server: Apart from Admin Server any weblogic server instance is called Managed server. To prevent the Administration Server from becoming a single point of failure, Managed Servers can always function without the presence a running Administration Server. When a Managed Server starts, it contacts the Administration Server to retrieve its configuration information. If a Managed Server is unable to connect to the specified Administration Server during startup, it can retrieve its configuration directly by reading a copy of the config.xml file and other files located on the Managed Server's own file system.

Cluster: A WebLogic Server cluster consists of multiple WebLogic Server instances running simultaneously and working together to provide increased scalability and reliability. A cluster appears to clients to be a single WebLogic Server instance. The server instances that constitute a cluster can run on the same machine, or be located on different machines. You can increase a cluster’s capacity by adding additional server instances to the cluster on an existing machine, or you can add machines to the cluster to host the incremental server instances. Each server instance in a cluster must run the same version of WebLogic Server.

A cluster is defined as a group of application servers that transparently run a J2EE application as if it were a single entity.  There are two methods of clustering:  vertical scaling and horizontal scaling

Horizontal clustering: It involves running multiple Java application servers that are run on two or more separate physical machines. Horizontal scaling is more reliable than vertical scaling, since there are multiple machines involved in the cluster environment, as compared to only one machine.
 Vertical clustering: However, consists of multiple Java application servers on a single physical machine. With vertical scaling, the machine's processing power, CPU usage, and JVM heap memory configurations are the main factors in deciding how many server instances should be run on one machine

Proxy Server: Proxy Server is an intermediary server between your web browser (client) which requests for some information/data and your server (web server/Application server) that process the data.

Types of Proxy Server: They are three different types of proxy servers. They are as follows

1) Forward Proxy Servers: Forward Proxy Server is a server which forwards the request from the intranet clients (web browser) to the internet servers. These proxy servers are present in the same network of your client.

2) Open Proxy Server: An open proxy is a proxy server which is accessible by any Internet user. Any proxy server that doesn’t restrict its client base to its own set of clients and allows any other client to connect to it is known as an “Open Proxy”. An anonymous open proxy allows users to conceal their IP address while browsing the Web or using other Internet services. They are in numerous open proxy servers present in Internet. For converting any flavor of proxy servers to Open Proxy servers we just have to enable the flag “ProxyRequests On” in the configuration file.

3) Reverse Proxy Server: A Proxy Server which takes requests from external clients (web browsers) or Internet and forwards them to servers in an internal network is called as Reverse Proxy Server. Generally, the reverse proxy servers are present in the same network where we have our App/Web servers.

Advantages of using Reverse Proxy Servers: The various advantages of using the proxy servers are as follows

1)      Filtering

2)      Caching

3)      Bypassing filters and censorship

4)      Logging and eavesdropping

5)      Gateways to private networks

6)      Accessing services anonymously

Fire wall: It provide filtering, autherization& Authentication services.

                  It can act as proxy servers.

      Mapping port requests.

Machine: A machine is a computer that host WebLogic server.

                  A machine runs a supported o.s platform.

Can host multiple WebLogic server instances.



WebLogic server Life Cycle:

Starting state: During the starting state  instances read the domain configuration data from its configuration directory. Whereas the Manager server will get their configuration data from Admin server. It is in this state that the instance the basic services such as the kernel and execute queues, the container service for logging and Node manager service. The server also deploy during this phase.

Stand by: In this state the server Instance will allow you to issue just to administrative requests. You can me the server state either running or shutdown state. Normally the server instance will automatically transition through the stand by state to next stage unless you start the instance with the start in stand by command.

Note: All ports are closed in this stat. But you can quickly transition to a running state.

Admin mode: The admin mode permits only Administrative task, deploying applications with those applications being able to only request from users with the admin and App tester roles. Running a server in admin mode is also useful when trying to diagnose problems with application gone badly.

Note: Servers will run in admin mode when there is problem with deployed application or JDBC connection pool.we can resume the server from Admin state to resume state.

Resuming state: This is purely transitional state the server instance goes through after it transitions automatically through Admin state or you issue the resume command after first placing the instance in the stand by or Admin state. You can do this state change from command line or through the Admin console.

Running state: This is off course final state the server instance reaches after you either issue a start up command or resume command to move the server out of the Admin or stand by state. It is in the running state that the server can accept the service client request for it services.

Generic Package Installation Steps
Note:

Generic Package installer:

. It does not include JAVA runtime. (When using "Generic Package installer" it is a prerequisite that a supported JDK should be installed)
. If you want to install Weblogic server with 64bit JVM, you have to use "Generic Package installer"
. "Generic Package installer" is platform independent and can be used to install weblogic server on any supported 32bit or 64bit platform.

As explained earlier there are three different ways of installing Oracle Weblogic Server:

1. Graphical mode
2. Console mode
3. Silent mode

Generic installer is platform independent so the installation steps are common fro any supported OS versions with a few exceptions that will be mentioned in braces
-------------------------------------------------------------------------------------------------------------------------

1) Graphical mode:

Step 1: Log in to the target system.
Step 2: Add the bin directory of the appropriate JDK to the beginning of the PATH variable definition on the target system.
Step 3: For example: PATH=$JAVA_HOME/bin:$PATHexport PATH (Unix/Linux) or
set PATH=%JAVA_HOME%/bin;%PATH% (Windows)
Step 4: Go to the directory where you downloaded the installation program.
Step 5: Launch the installation program by entering the following command (this example shows the NET installer):
java -jar net_wlsversion_generic.jar
The installation program begins to install the software.
Step 6: Once the installation preparation is complete you will see the welcome screen
Screen:

Step 7: Click Next

Step 8: If there are existing Middleware Home Directories it will list all of them.
You may either select an existing Middleware Home Directory or create a new one.

Note: It is always recommended to have one Middleware Home Directory per installation, so I'll select "Create a new Middleware Home"

Step 9: Click Next

Step 10: If you want to register for Security updates enter  your My Oracle Support credentials or else un-check the box, it will prompt to bypass click Yes
and then
click Next.

Step 11: Click Next

Step 12: Click Next

Step 13: Click Next to All Users to access the Oracle Weblogic Server Installation.

Step 14: Click Next ( Make sure the more then 1289.8 MB of space is available in the Middleware Home)

Step 15: Wait for the installation to complete.

OS-Specific Package Installation:

There are 3 types of installations

1. GUI mode.

2. Console mode.

3. Silent mode.

1) GUI Mode: 

Step1: welcome screen

Step2: Accept license agreement.

Step3: Create new BEA home directory

C:\bea10.3

Step4: Choose installation- Complete (or) Custom

Step5: Select complete

Step6: Select product installation directory

          C:\bea10.3\wlserver_10.3

2) Console Mode:

       server10.3_win32.exe  -mode = console

3) Silent Mode:   It is a way of setting installation configuration only once and then using those configurations to duplicate the installation on many machines.

The installation programs read the settings for your configuration from an xml file.(silent.xml)

server10.3_win32.exe -mode=silent -silent.xml=c:\bea10.3\silent.xml  -log=c:\10.3\silent.log


Step 1: Create silent.xml file

<?xml version="1.0" encoding="ISO-8859-1" ?>

<bea-installer>

<input-fields>

<data-value name="BEAHOME" value="C:\bea10.3" />

<data-value name="USER_INSTALL_DIR" value="C:\bea10.3\wlserver_10.3" />

</input-fields>

</bea-installer>

Step 2: Save this file as silent.xml file in C:\bea10.3 folder

Step 3: Copy the WebLogic software under C:\bea10.3 folder

Step 4: Create a sub folder wlserver_10.3 under c:\bea10.3

Step 5: Execute the below command

server103_win32.exe -mode=silent -silent_xml=C:\bea10.3\ silent.xml  -log=C:\10.3\silent.log

Domain creation using configuration wizard:

Step 1: Goto the below path and execute config.cmd script

            C:\bea10.3\wlserver_10.3\common\bin>config.cmd

Step 2: Select - Create new WebLogic domain

Step 3: Select - Base this domain on an existing template

Step 4: Configure Administrator username and password.

Step 5: Configure server start mode and JDK

             Development mode ---- SunJdk

             Production mode ----- Jrocket

             Select development mode and SunJdk

Step 6: Customize environment & services settings

            Select yes if you would like to configure resources

Step 7: Configure Admin server

             Name : AdminServer

             Listen address: localhost

             Listen port : 7001

             SSL listen: None

             Default port number for AdminServer-7001

              Default ssl listen port : 7002

Step 8: Configure managed servers

             name listen address listen port ssl listen port

             ms1 localhost 7003 None

             ms2 localhost 7004 None

Step 9: Configure cluster

            Name Multicast address multicast port cluster address

            c1 239.192.0.0 7010 localhost:7003, localhost:7004

Step 10: Assign servers to clusters

Step 11: Configure machines

               Name NodeManagerListenAddress NodeManagerListenPort

               m1 localhost 5556

Step 12: Assign servers to machines

Step 13: Create WebLogic domain

              Enter the name and location for the domain

              Domain name : dev_domain

              Domain location : c:\bea10.3\user_projects\domains

Step 14: Click on Create

Shell Script and Sample Programs

SHELL SCRIPTING

SHELL: -shell is command line interpreter. It takes commands from user and executes them. it is an interface between user and kernel.  The three most widely used UNIX shells are Bourne shell .kom shell and c shell.

Shell	Developed by	Shell Prompt	Execution Command
Bash shell	Denis Richie	$	sh
Bourne shell	Steven courne	$	Sh
Korn shell	David korn	$	Ksh
C shell	Bill joy, california university student	%	Csh

Each shell has merits and demerits of its own. Moreover the shell scripts written for one shell may not work with the other shell. This is because different shells use different shells use different mechanism to execute the commands in the shell script. Bourne shell since it is one of the most widely used UNIX shells in existence today.

      Almost all UNIX implementations offer the Bourne shell as part of their standard configuration. It is smaller than the other two shells and therefore more efficient for most shell processing. However it lacks features offered by the c and korn shell.

      All shell programs written for the Boume shell are likely to work with the korn shell, the reverse however may not be true, this is so since the facilities like arrays, command aliasing and history mechanism available in the korn shell are not supported by the bourne shell.

The c shell programming language resembles the c language and is quite different from the language of the bourne shell, only the very basic shell scripts will run under both the c and bourne shell; a vast majority will not shell keeps track of commands as you enter them (history) and allows you to go back and execute them again without typing the command. Or, if you want to, you can recall them, make modifications, and then execute the new command.

chsh

Shell program:-

     A shell program is nothing but a series of such commands, instead of specifying one job at a time, we give the shell a to -do list —a program — that carries out an entire procedure. such programs are known as “shell scripts”.

When to use shell scripts:

1. Customizing your work  environments, for example, every time you log in if                                                  you want to see the current date, a welcome message and the list of users who have logged in you can write a shell script for the same.
2. automating your daily tasks, for example, you a may want to back up all your programs at the end of day, this can be done using a shell script.
3. Automating repetitive tasks. f xth1e, the repetitive task of compiling a c program, linking it with some libraries and executing the executable code can be a shell script.
4. Executing important system procedures like shutting down the system, formatting a disk, creating a file system, mounting the file system, letting the user the floppy and finally unmounting the disk.
5. Performing same operation on many files. Or example, you may want to rep lace a string with a string myprintf in all the c programs present in a directory

Shell Variables:-

           Variable is, a data name and it is used to store value. Variable value can change during execution of the program.

Variables in UNIX are two types.

1. Unix-defined variables or system variables

2. User defined variables

Unix-defined variables:

          These are standard variables which are always accessible the shell provides the values for these variables these variable are usually used by the system itself and govern the environment we work under. If we so desire we can change the values of these variables as per our preferences and customize the system environment.

          The list of all system variables and their values can be displayed by

Saying at the $prompt,

$set

HOME=/usr/sv

HZ=100

IFS=

LOGNAME=sv

MAII=usr/spool/mail/sv

MAILCHECK=600

OPTINd=l

PATH=/bin :Iusr/b in:/usr/sv:/bin:.

PS1=$

SHELL=/bin/sh

TERM=vt100

TZ=IST-5:30

Variable	Meaning
PS1	Primary shell prompt
PS2	The system prompt 2, default value is “>”
PATH	Defines the path which the shell must search in order to execute any command or file
HOME	Stores the de fault working directory of the user
LOGMAN	Stores the login name of  the user
MAIL	Defines the file where the mail of the user is stored
MAILCHECK	Defines the duration after which the shell checks whether the user has received any mail. By default its value is 600(seconds)
IFS	Defines the name of your default working shell
SHELL	Defines the name of your default working shell
TERM	Define the name of the terminal zone in which you are working
TZ	Defines the name of the Zone in which we are working

User Defined Variables

 These are defined by user and are used most extensively in shell programming.

Rules for creating User Defined Shell Variables: -

1.   The first character of a variable name should be alphabet or underscore.

2.   No commas or blanks are allowed within a variable name

3.   Variables names should be of any reasonable length

4.   Variable names are case sensitive, that isName, nAme, name are all different variable names.

5.   Variable name shouldn’t be a reserve word

Shell Keywords:-

Keywords are the Words whose meaning has already been explained to the shell. The keywords are .also called as “Reserve Words”.

The lists of keywords available in Bourne shell are

Echo if Read else Set fi unset while Readonly do Shift Done Export For

Until trap case wait esac eval break exec continue ulimit Exit Umask return

1.Echo

             echo command is used to display the messages on the screen and is used to display the value stored in a shell variable.

Eg 1: $echo “Multics is a training institute”

            Multics is a training institute

Note: double quotes are option in echo statement.

Eg 2: $echo “today date is:`date`”

            Today date is sat mar 4 o4:40:i0 1ST 2005

Note: the UNIX command should be in back quotes in echo statement

Otherwise it treats, as text.

Eg 3: $echo “my file has we —I file lines

               My file has 10 lines

Eg 4: $echo my log name is:`logname`.

             My logname is Sv

Eg 5: $echo “my present working directory is :`pwd` ”

                My present working directory is :/usr/sv/abc

Shell variables

Eg 1: $a=10

Note: there are no predefined data types in UNIX. Each and every thing it treats as character. Each character occupies 1 byte of memory.

Eg 2:$b2000

In above example a occupies 2 bytes and b occupies 4 bytes of memory

Reading of variable

               $ is the operator to read variable value

Eg 1: $n=l00

          $echo $n

             100

Eg 2: $name=”Multics”

          $echo $name

              Multics

$echo welcome to $name

Welcome to Multics

Eg 3: $now=`date`

          $$now

           sat mar 4 o4:40:10 1ST 2005

Eg 4: $mypath=/usr/sv/abc/a 1 /a2

           $cd $mypath

now it changes to a2 directory, to check say at $ promt pwd command $pwd

/usr/sv/abc/a 1 /a2

Null Variables

 A variable which has been defined but has not been given any value is known as a null variable. A null variable can be created in any of the following ways.

1.$n=””

2.$n=”

3.$n=

$echo n

on echoing a null variable, only a blank line appears on the screen.

Constant:

Constant is a fixed value. It doesn’t change during execution of  the  program

$a=20

$readonly  a

When the variable are made readonly, the shell doe not allow us to change their values, so a value can read but can‘t change.

Note: If we want the shell to forget about a variable altogether, we use the unset command.

$unset  a

on issuing the above command the variable a and with it the value assigned to it are erased from the shell’s memory.

Shell Programs

1. WAS,to display list of files, the current working user‘s list and present working directory

$vi sp1

ls -x

who

pwd

:wq(save and quit)

Execution of shell program:

Sh is the command to execute bourn shell programs

eg: $sh sp1

or

$chmod 744 sp1

$./sp1

2)WAS, to display address

$vi sp2

echo “Multics Scripting Institute”

echo “No:109, 1^st floor”

echo “Eurekha court,”

echo “4^th floor”

echo “Ameerpet,”

echo “Hyderabad”

:wq(save and quit)

3)WAS, to  count no of users are currently logged into the system

$vi sp3.sh

echo “There are `who |  wc  -l ` users”

:wq(save and quit)

Configuring Managed Servers for Oracle WebLogic Server

Configuring SSL Between the Apache HTTP Server Plug-In and WebLogic Server

Using SSL with Apache Plug-in

You can use the SSL protocol to protect the connection between the Apache HTTP Server Plug-In and WebLogic Server.

The SSL provides confidentially and integrity to the data passed between the Apache HTTP Server Plug-In and WebLogic Server.

The Apache HTTP Server Plug-In does not use the transport protocol (http or https) specified in the HTTP request (usually by the browser) to determine whether or not the SSL protocol is used to protect the connection between the Apache HTTP Server Plug-In and WebLogic Server.

Although two-way SSL can be used between the HTTP client and Apache HTTP server, note that one-way SSL is used between Apache HTTP Server and WebLogic Server.


Configuring SSL Between the Apache HTTP Server Plug-In and WebLogic Server

To use the SSL protocol between Apache HTTP Server Plug-In and WebLogic Server::

1. Configuring WebLogic Server for SSL.

2. Configure the WebLogic Server SSL listen port.

3. In the Apache Server, set the WebLogicPort parameter in the httpd.conf file to the WebLogic Server SSL listen port configured in Step 2.

4. In the Apache Server, set the SecureProxy parameter in the httpd.conf file to ON.

5. Set any additional parameters in the httpd.conf file that define information about the SSL connection. Forr a complete list of the SSL parameters that you cab configure for the plug-in.



Issues with SSL-Apache Configuration

These known issues arise when you configure the Apache plug-in to use SSL:

  . To prepare the plugin configuration, double click the lock and go to the certificates path:
     * Select the root CA (at the top)

     * Display it

     * Detail and then copy this certificate to a file using the Coded "Base

       64 X509" option

     * Save the file, for example, to ýMyWeblogicCAToTrust.cerý (which is also a PEM file)

  . The PathTrim parameter must be configured inside the <Location> tag.
 
    The following configuration is incorrect:

<Location /weblogic>
SetHandler weblogic-handler
</Location>

<IfModule mod_weblogic.c>
WebLogicHost localhost
WebLogicPort 7001
PathTrim /weblogic
</IfModule>

The following configuration is correct setup:

<Location /weblogic>
SetHandler weblogic-handler
PathTrim /weblogic
</Location>

  . Thee Include directive does not work with Apache SSL. You must configure all parameters directly in the httpd.conf file. Do not use the following configuration when using SSL:

    <IfModule mod_weblogic.c>
     MatchExpression *.jsp
     Include weblogic.conf
    <IfModule>

  . The current implementation of the WebLogic Server Apache Plug-In does not support the use of multiple certificate files with Apache SSL.





Possible Causes of Connection Failures

Failure of the WebLogic Server host to respond to a connection request could indicate the following problems:

 . Physical problems with the host machine

 . Network problems

 . Other server failures

 Failure of all WebLogic Server instances to respond could indicate the following problems:

 . WebLogic Server is not running or is unavailable

 . A hung server

 . A database problem

 . An application-specific failure