4 Installing and Configuring the Apache HTTP Server Plug-In

This chapter describes how to install and configure the Apache HTTP Server plug-in. It contains the following sections:

Note:

For proxying requests from Oracle HTTP Server to Oracle WebLogic Server, use the mod_wl_ohs plug-in, which is similar to the plug-in for Apache HTTP Server, but need not be downloaded and installed separately. For information about configuring mod_wl_ohs, see Chapter 2, "Configuring the mod_wl_ohs Plug-In for Oracle HTTP Server.".

4.1 Install the Apache HTTP Server Plug-In

After you download the Apache HTTP Server plug-in as described in Section 1.2, "Availability of Version 1.1 Plug-Ins,", you can install it as an Apache HTTP Server module in your Apache HTTP Server installation.

4.1.1 Installation Prerequisites

Before you install the Apache HTTP Server plug-in, do the following:

  • Download the Apache HTTP Server plug-in, as described in Section 1.2, "Availability of Version 1.1 Plug-Ins."

  • Plug-in zip extract location (PLUGIN_HOME; for example /home/myhome/weblogic-plugins-1.1/)

  • Extract the plug-ins zip distribution to PLUGIN_HOME; for example, /home/myhome/weblogic-plugins-1.1/. This distribution contains these files:

    Table 4-1 Files Included in the Apache Web Server Plug-in Zip

    (path)/filename Description

    README.txt

    This file

    bin/orapki.bat

    orapki tool for configuring Oracle wallets

    jlib/*.jar

    orapki helper Java libraries

    lib/mod_wl.so

    WebLogic proxy module

    lib/*.so(.dll)

    Helper libraries


  • Install JDK 7 if you want to use SSL. The JDK 7 installation is required to use the orapki utility, which manages public key infrastructure (PKI) elements, such as wallets and certificate revocation lists, for use with SSL.

  • Ensure that you have a supported Apache HTTP Server installation.

    Note:

    If you intend to use Apache HTTP Server 2.4, then please upgrade to 12.1.x plug-ins.

    For more information, see:

    http://www.oracle.com/technology/software/products/ias/files/fusion_certification.html.

  • Ensure that a supported version of Oracle WebLogic Server is configured and running on a target system. Note that this server does not need to be running on the system on which you extracted the plug-in zip distribution. For the supported Oracle WebLogic Server versions, see:

    http://www.oracle.com/technology/software/products/ias/files/fusion_certification.html.

4.1.2 Installing the Apache HTTP Server Plug-In

The Apache HTTP Server plug-in is distributed as a shared object (.so) file.

To install the Apache HTTP Server plug-in:

  1. Make sure that the weblogic-plugins-1.1/lib folder is included in LD_LIBRARY_PATH on Unix systems (and PATH on Windows systems). If you do not do this, you see linkage errors when starting Apache HTTP Server.

  2. In the location where you unzipped the downloaded plug-in file, locate lib/mod_wl.so; for example, /home/myhome/weblogic-plugins-1.1/lib/mod_wl.so.

  3. Verify that the mod_so.c module is enabled.

    If you installed Apache HTTP Server using the script supplied by Apache, mod_so.c is already enabled. Verify that mod_so.c is enabled by executing the following command on the UNIX/Linux platform:

    APACHE_HOME/bin/apachectl -l
    

    (APACHE_HOME is the directory that contains the Apache HTTP Server installation.)

    Note:

    The apachectl command is not available on the Windows platform.

    This command lists all enabled modules. If mod_so.c is not listed, you must rebuild your Apache HTTP Server, making sure that the following configure option is specified:

    ...
    --enable-module=so
    ...
    
  4. Make a copy of the APACHE_HOME/bin/httpd.conf file for backup.

  5. Open the httpd.conf file.

  6. Install the Apache HTTP Server plug-in module for Apache 2.2.x by adding the following line. For Windows, specify the .dll file.

    LoadModule weblogic_module /home/myhome/weblogic-plugins-1.1/lib/mod_wl.so
    
  7. Verify the syntax of the httpd.conf file by running the following command:

    • Windows

      APACHE_HOME\bin> apachectl -t
      
    • UNIX/Linux

      > APACHE_HOME/bin/apachectl -t
      

    If the httpd.conf file contains any errors, the output of this command shows the errors; otherwise, the command returns the following:

    Syntax OK
    

4.2 Configure the Apache HTTP Server Plug-In

This section describes how to edit the httpd.conf file to proxy requests by path or by MIME type, to enable HTTP tunneling, and to use other Oracle WebLogic Server plug-in parameters.

4.2.1 Editing the httpd.conf File

Edit the httpd.conf file in your Apache HTTP Server installation to configure the Apache HTTP Server plug-in.

  1. Open the httpd.conf file, if it is not already open.

  2. To proxy requests by MIME type, add an IfModule block that defines one of the following:

    • For a non-clustered WebLogic Server: the WebLogicHost and WebLogicPort parameters.

    • For a cluster of WebLogic Servers: the WebLogicCluster parameter.

    Example:

    <IfModule mod_weblogic.c>
     WebLogicHost myweblogic.example.com
     WebLogicPort 7001
     Debug ALL
     DebugConfigInfo ON
     WLLogFile /tmp/wl-proxy.log 
    </IfModule>
    
  3. To proxy requests by MIME type, add a MatchExpression line to the IfModule block. Note that if both MIME type and proxying by path are enabled, proxying by path takes precedence over proxying by MIME type.

    For example, the following IfModule block for a non-clustered WebLogic Server specifies that all files with MIME type .jsp are proxied:

    <IfModule mod_weblogic.c>
     WebLogicHost my-weblogic.server.com
     WebLogicPort 7001
     MatchExpression *.jsp
     Debug ALL
     DebugConfigInfo ON
     WLLogFile /tmp/wl-proxy.log 
    </IfModule>
    

    You can also use multiple MatchExpressions, for example:

    <IfModule mod_weblogic.c>
     WebLogicHost my-weblogic.server.com
     WebLogicPort 7001
     MatchExpression *.jsp
     MatchExpression *.xyz
     Debug ALL
     DebugConfigInfo ON
     WLLogFile /tmp/wl-proxy.log 
    </IfModule>
    

    If you are proxying requests by MIME type to a cluster of WebLogic Servers, use the WebLogicCluster parameter instead of the WebLogicHost and WebLogicPort parameters. For example:

    <IfModule mod_weblogic.c>
     WebLogicCluster w1s1.com:7001,w1s2.com:7001,w1s3.com:7001
     MatchExpression *.jsp
     MatchExpression *.xyz
    </IfModule>
    
  4. To proxy requests by path, use the Location block and the SetHandler statement. SetHandler specifies the handler for the Apache HTTP Server plug-in module. For example the following Location block proxies all requests containing /weblogic in the URL:

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

    The PathTrim parameter specifies a string trimmed from the beginning of the URL before the request is passed to the WebLogic Server instance (see Section 7.1, "General Parameters for Web Server Plug-Ins").

  5. The PathTrim parameter must be configured inside the <Location> tag. These known issues arise when you configure the Apache plug-in to use SSL

    • 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 the correct setup:

      <Location /weblogic>
       SetHandler weblogic-handler
       PathTrim /weblogic
      </Location>
      
    • The current implementation of the WebLogic Server Apache plug-in does not support the use of multiple certificate files with Apache SSL.

  6. Optionally, enable HTTP tunneling for t3 or IIOP protocol and weblogic.jar, add the following Location block to the httpd.conf file:.

    <Location /bea_wls_internal/HTTPClnt>
     SetHandler weblogic-handler
    </Location>
    
  7. Define any additional parameters for the Apache HTTP Server plug-in.

    The Apache HTTP Server plug-in recognizes the parameters listed in Section 7.1, "General Parameters for Web Server Plug-Ins". To modify the behavior of your Apache HTTP Server plug-in, define these parameters either:

    • In a Location block, for parameters that apply to proxying by path, or

    • At global or virtual host scope, for parameters that apply to proxying by MIME type.

  8. Verify the syntax of the httpd.conf file by running the following command on the UNIX/Linux platform:

    > APACHE_HOME/bin/apachectl -t
    

    Note:

    The apachectl command is not available on the Windows platform.

    If the httpd.conf file contains any errors, the output of this command shows the errors; otherwise, the command returns the following:

    Syntax OK
    
  9. Start the Apache HTTP Server.

    • Windows

      APACHE_HOME\bin> httpd -k start
      
    • UNIX/Linux

      > APACHE_HOME/bin/apachectl start
      
  10. Send a request to http://apache-host:apache-port/mywebapp/my.jsp from the browser. Validate the response.

4.2.1.1 Placing WebLogic Properties Inside Location or VirtualHost Blocks

If you choose to not use the IfModule, you can instead directly place the WebLogic properties inside Location or VirtualHost blocks. Consider the following examples of the Location and VirtualHost blocks:

<Location /weblogic>
SetHandler weblogic-handler
WebLogicHost myweblogic.server.com
WebLogicPort 7001
</Location>
 
<Location /weblogic>
SetHandler weblogic-handler
WebLogicCluster w1s1.com:7001,w1s2.com:7001,w1s3.com:7001
</Location>
 
<VirtualHost apachehost:80>
SetHandler weblogic-handler
WebLogicServer weblogic.server.com
WebLogicPort 7001
</VirtualHost>

4.2.1.2 Example: Configuring the Apache Plug-In

The following example demonstrates basic instructions for quickly setting up the Apache plug-in to proxy requests to a backend WebLogic Server:

  1. Make a copy of ${APACHE_HOME}/conf/httpd.conf file.

  2. Edit the file to add the following code:

    ...   LoadModule weblogic_module /home/myhome/weblogic-plugins-1.1/lib/mod_wl.so
    
      <IfModule mod_weblogic.c>
        WebLogicHost wls-host
        WebLogicPort wls-port
        Debug ALL
        WLLogFile /tmp/wl-proxy.log
      </IfModule>
    
      <Location /mywebapp>
        SetHandler weblogic-handler
      </Location>
      ...
    
  3. Include ${PLUGIN_HOME}/lib in the LD_LIBRARY_PATH by entering the following command:

     $ export LD_LIBRARY_PATH=/home/myhome/weblogic-plugin-1.1/lib:...
    

    Note:

    You can also update the PATH by copying the 'lib' contents to APACHE_HOME\lib or by editing the APACHE_HOME/bin/apachectl to update the LD_LIBRARY_PATH.
  4. At the prompt, start the apache server by entering:

    $ ${APACHE_HOME}/bin/apachectl start
    
  5. Send a request to http://apache-host:apache-port/mywebapp/my.jsp from the browser and validate the response

4.2.2 Including a weblogic.conf File in the httpd.conf File

If you want to keep several separate configuration files, you can define parameters in a separate configuration file called weblogic.conf file, by using the Apache HTTP Server Include directive in an IfModule block in the httpd.conf file:

<IfModule mod_weblogic.c>
 # Config file for WebLogic Server that defines the parameters
 Include conf/weblogic.conf 
</IfModule>

The syntax of weblogic.conf files is the same as that for the httpd.conf file.

This section describes how to create weblogic.conf files, and includes sample weblogic.conf files.

4.2.2.1 Creating weblogic.conf Files

Be aware of the following when constructing a weblogic.conf file.

  • Enter each parameter on a new line. Do not put "=" between a parameter and its value. For example:

    PARAM_1 value1
    PARAM_2 value2
    PARAM_3 value3
    
  • If a request matches both a MIME type specified in a MatchExpression in an IfModule block and a path specified in a Location block, the behavior specified by the Location block takes precedence.

  • If you use an Apache HTTP Server <VirtualHost> block, you must include all configuration parameters (MatchExpression, for example) for the virtual host within the <VirtualHost> block (see Apache Virtual Host documentation at http://httpd.apache.org/docs/vhosts/).

  • If you want to have only one log file for all the virtual hosts configured in your environment, you can achieve it using global properties. Instead of specifying the same Debug, WLLogFile and WLTempDir properties in each virtual host you can specify them just once in the <IfModule> tag.

  • Sample httpd.conf file:

    <IfModule mod_weblogic.c>
     WebLogicCluster johndoe02:8005,johndoe:8006
     Debug ON
     WLLogFile c:/tmp/global_proxy.log 
     WLTempDir "c:/myTemp"
     DebugConfigInfo ON
     KeepAliveEnabled ON
     KeepAliveSecs 15
    </IfModule>
    
    <Location /jurl>
     SetHandler weblogic-handler
     WebLogicCluster agarwalp01:7001
    </Location>
    
    <Location /web>
     SetHandler weblogic-handler
     PathTrim /web
     Debug OFF
     WLLogFile c:/tmp/web_log.log
    </Location>
     
    <Location /foo>
     SetHandler weblogic-handler
     PathTrim /foo
     Debug ERR
     WLLogFile c:/tmp/foo_proxy.log
    </Location>
    
  • All the requests which match /jurl/* will have Debug Level set to ALL and log messages will be logged to c:/tmp/global_proxy.log file. All the requests which match /web/* will have Debug Level set to OFF and no log messages will be logged. All the requests which match /foo/* will have Debug Level set to ERR and log messages will be logged to c:/tmp/foo_proxy.log file.

  • Oracle recommends that you use the MatchExpression statement instead of the <Files> block.

4.2.2.2 Sample weblogic.conf Configuration Files

The following examples of weblogic.conf files may be used as templates that you can modify to suit your environment and server. Lines beginning with # are comments.

Example 4-1 Example Using WebLogic Clusters

# These parameters are common for all URLs which are 
# directed to the current module. If you want to override
# these parameters for each URL, you can set them again in
# the <Location> or <Files> blocks. (Except WebLogicHost,
# WebLogicPort, WebLogicCluster, and CookieName.)

<IfModule mod_weblogic.c>
 WebLogicCluster w1s1.com:7001,w1s2.com:7001,w1s3.com:7001
 ErrorPage http://myerrorpage.mydomain.com
 MatchExpression *.jsp
</IfModule>
####################################################

In Example 4-2, the MatchExpression parameter syntax for expressing the filename pattern, the WebLogic Server host to which HTTP requests should be forwarded, and various other parameters is as follows:

MatchExpression [filename pattern] [WebLogicHost=host] | [paramName=value]

The first MatchExpression parameter below specifies the filename pattern *.jsp, and then names the single WebLogicHost. The paramName=value combinations following the pipe symbol specify the port at which WebLogic Server is listening for connection requests, and also activate the Debug option. The second MatchExpression specifies the filename pattern *.html and identifies the WebLogicCluster hosts and their ports. The paramName=value combination following the pipe symbol specifies the error page for the cluster.

Example 4-2 Example Using Multiple WebLogic Clusters

# These parameters are common for all URLs which are 
# directed to the current module. If you want to override
# these parameters for each URL, you can set them again in
# the <Location> or <Files> blocks (Except WebLogicHost,
# WebLogicPort, WebLogicCluster, and CookieName.)

<IfModule mod_weblogic.c>
 MatchExpression *.jsp WebLogicHost=myHost|WebLogicPort=7001|Debug=ON
 MatchExpression *.html WebLogicCluster=myHost1:7282,myHost2:7283|ErrorPage=
 http://www.xyz.com/error.html
</IfModule>

Example 4-3 shows an example without WebLogic clusters.

Example 4-3 Example Without WebLogic Clusters

# These parameters are common for all URLs which are 
# directed to the current module. If you want to override
# these parameters for each URL, you can set them again in
# the <Location> or <Files> blocks (Except WebLogicHost,
# WebLogicPort, WebLogicCluster, and CookieName.)
<IfModule mod_weblogic.c>
 WebLogicHost myweblogic.server.com
 WebLogicPort 7001
 MatchExpression *.jsp
</IfModule>

Example 4-4 shows an example of configuring multiple name-based virtual hosts.

Example 4-4 Example Configuring Multiple Name-Based Virtual Hosts

# VirtualHost1 = localhost:80
<VirtualHost 127.0.0.1:80>
DocumentRoot "C:/test/VirtualHost1"
ServerName localhost:80
<IfModule mod_weblogic.c> 
#... WLS parameter ...
WebLogicCluster localhost:7101,localhost:7201
# Example: MatchExpression *.jsp <some additional parameter>
MatchExpression *.jsp PathPrepend=/test2
</IfModule>
</VirtualHost>
 
# VirtualHost2 = 127.0.0.2:80
<VirtualHost 127.0.0.2:80>
DocumentRoot "C:/test/VirtualHost1"
ServerName 127.0.0.2:80
<IfModule mod_weblogic.c> 
#... WLS parameter ...
WebLogicCluster localhost:7101,localhost:7201
# Example: MatchExpression *.jsp <some additional parameter>
MatchExpression *.jsp PathPrepend=/test2
#... WLS parameter ...
</IfModule>
</VirtualHost>

You must define a unique value for ServerName or some plug-in parameters will not work as expected.

4.2.2.3 Template for the Apache HTTP Server httpd.conf File

This section contains a sample httpd.conf file for Apache 2.2. You can use this sample as a template and modify it to suit your environment and server. Lines beginning with # are comments.

Note that Apache HTTP Server is not case sensitive.

Example 4-5 Sample httpd.conf file for Apache 2.2

####################################################
APACHE-HOME/conf/httpd.conf file
####################################################
LoadModule weblogic_module lhome/myhome/weblogic-plugins-1.1/lib/mod_wl.so

<Location /weblogic>
 SetHandler weblogic-handler
 PathTrim /weblogic
 ErrorPage http://myerrorpage1.mydomain.com
</Location>

<Location /servletimages>
 SetHandler weblogic-handler
 PathTrim /something
 ErrorPage http://myerrorpage1.mydomain.com
</Location>

<IfModule mod_weblogic.c>
  MatchExpression *.jsp
  WebLogicCluster w1s1.com:7001,w1s2.com:7001,w1s3.com:7001
  ErrorPage http://myerrorpage.mydomain.com
</IfModule>