3 Configuring WLS Web Server Proxy Plug-In for Apache HTTP Server

This chapter describes how to install and configure the WLS Web Server Proxy Plug-In for Apache HTTP Server. 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 WebLogic Proxy Plug-In for Oracle HTTP Server.".

3.1 Support Note

The WLS Web Server Proxy Plug-In for Apache HTTP Server is supported on Apache web servers and is able to front-end WebSocket applications. Support is described in the Certification matrix, at:

http://www.oracle.com/technetwork/middleware/ias/downloads/fusion-certification-100350.html

Note that this URL points to the Certification Central Page, so you need to copy the correct module based on your web server version. To obtain certifications for the WLS Plug-in, choose the spreadsheet document in the list associated with your FMW/WLS version (for example, 12.1.2.0) and then open the "webservers" tab.

3.2 Install the WLS Web Server Proxy Plug-In for Apache HTTP Server

After you download the WLS Web Server Proxy Plug-In for Apache HTTP Server, as described in Section 1.2, "Availability of WLS Web Server Proxy Plug-In 12.1.2,", you can install it as an Apache HTTP Server module in your Apache HTTP Server installation.

3.2.1 Installation Prerequisites

Before you install the WLS Web Server Proxy Plug-In for Apache HTTP Server, do the following:

  • Download the WLS Web Server Proxy Plug-In for Apache HTTP Server, as described in Section 1.2, "Availability of WLS Web Server Proxy Plug-In 12.1.2."

  • Plug-in zip extract location (PLUGIN_HOME; for example /home/myhome/weblogic-plugins-12.1.2/)

  • Extract the plug-ins zip distribution to PLUGIN_HOME; for example, /home/myhome/weblogic-plugins-12.1.2/. This distribution contains these files:

    Table 3-1 Files Included in the Apache Web Server Plug-in Zip

    (path)/filename Description

    README.txt

    The README file for the plug-in.

    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 6 if you want to use SSL. The JDK 6 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.

    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.

3.2.2 Installing the Apache HTTP Server Plug-In

The WLS Web Server Proxy Plug-In for Apache HTTP Server is distributed as a shared object (.so) for Unix platforms and a DLL for Windows. You can obtain the plug-in from here:

To install the Apache HTTP Server plug-in:

  1. Make sure that the weblogic-plugins-12.1.2/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-12.1.2/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:

    • UNIX/Linux

      APACHE_HOME/bin/apachectl -l
      

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

    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.

    LoadModule weblogic_module /home/myhome/weblogic-plugins-12.1.2/lib/mod_wl.so
    
  7. Verify the syntax of the httpd.conf file by running the following command:

    • 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
    

3.3 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.

3.3.1 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
     DebugConfigInfo ON
    </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
     DebugConfigInfo ON
    </IfModule>
    

    You can also use multiple MatchExpressions, for example:

    <IfModule mod_weblogic.c>
     WebLogicHost my-weblogic.server.com
     WebLogicPort 7001
     MatchExpression *.jsp
     MatchExpression *.xyz
     DebugConfigInfo ON
    </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 WLSRequest statement. WLSRequest specifies the handler for the WLS Web Server Proxy Plug-In for Apache HTTP Server module. For example the following Location block proxies all requests containing /weblogic in the URL:

    <Location /weblogic>
    WLSRequest On
    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 WLS Web Server Proxy Plug-In for Apache HTTP Server to use SSL

    • The following configuration is incorrect:

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

      The following configuration is the correct setup:

      <Location /weblogic>
       WLSRequest On
       PathTrim /weblogic
      </Location>
      
    • The current implementation of the WLS Web Server Proxy Plug-In for Apache HTTP Server does not support the use of multiple certificate files with Apache SSL.

  6. Optionally, enable HTTP tunneling for t3 or IIOP.

    1. To enable HTTP tunneling if you are using the t3 protocol and weblogic.jar, add the following <Location> block to the httpd.conf file:

      <Location /bea_wls_internal>
       WLSRequest On
      </Location>
      
    2. To enable HTTP tunneling if you are using the IIOP, the only protocol used by the WebLogic Server thin client, wlclient.jar, add the following Location block to the httpd.conf file:

      <Location /bea_wls_internal>
       WLSRequest On
      </Location>
      
  7. Define any additional parameters for the WLS Web Server Proxy Plug-In for Apache HTTP Server.

    The WLS Web Server Proxy Plug-In for Apache HTTP Server recognizes the parameters listed in Section 7.1, "General Parameters for Web Server Plug-Ins". To modify the behavior of your WLS Web Server Proxy Plug-In for Apache HTTP Server, 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:

    • 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
    
  9. Start the Apache HTTP Server.

    • 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.

3.3.1.1 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>
WLSRequest On
WebLogicHost myweblogic.server.com
WebLogicPort 7001
</Location>
 
<Location /weblogic>
WLSRequest On
WebLogicCluster w1s1.com:7001,w1s2.com:7001,w1s3.com:7001
</Location>
 
<VirtualHost apachehost:80>
WLSRequest On
WebLogicServer weblogic.server.com
WebLogicPort 7001
</VirtualHost>

3.3.1.2 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-12.1.2/lib/mod_wl.so
    
      <IfModule mod_weblogic.c>
        WebLogicHost wls-host
        WebLogicPort wls-port
      </IfModule>
    
      <Location /mywebapp>
        WLSRequest On
      </Location>
      ...
    
  3. Include ${PLUGIN_HOME}/lib isd in the LD_LIBRARY_PATH by entering the following command:

     $ export LD_LIBRARY_PATH=/home/myhome/weblogic-plugin-12.1.2/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 HTTP 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

3.3.2 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.

3.3.2.1 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/).

  • Sample httpd.conf file:

    <IfModule mod_weblogic.c>
     WebLogicCluster johndoe02:8005,johndoe:8006
     WLTempDir "c:\myTemp"
     DebugConfigInfo ON
     KeepAliveEnabled ON
     KeepAliveSecs 15
    </IfModule>
    
    <Location /jurl>
     WLSRequest On
     WebLogicCluster agarwalp01:7001
     WLTempDir "c:\jurl
    </Location>
    
    <Location /web>
     WLSRequest On
     PathTrim/web
     WebLogicHost myhost
     WebLogicPort 8001
     WLTempDir "c:\web"
    </Location>
     <Location /foo>
     WLSRequest On
     WebLogicHost myhost02
     WebLogicPort 8090
     WLTempDir "c:\foo"
     PathTrim/foo
    </Location>
    
  • All the requests that match /jurl/* will have the POST data files in c:\jurl and will reverse proxy the request to agarwalp01 and port 7001. All the requests that match /web/* will have the POST data files in c:\web and will reverse proxy the request to myhost and port 8001. All the requests that match /foo/* will have the POST data files written to c:\foo and will reverse proxy the request to myhost02 and port 8090.

  • You should use the MatchExpression statement instead of the <Files> block.

3.3.2.2 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 3-1 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 3-2, 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 *.http and identifies the WebLogic Cluster hosts and their ports. The paramName=value combination following the pipe symbol specifies the error page for the cluster.

Example 3-2 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 3-3 shows an example without WebLogic clusters.

Example 3-3 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 3-4 shows an example of configuring multiple name-based virtual hosts.

Example 3-4 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.

3.3.2.3 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 3-5 Sample httpd.conf file for Apache 2.2

####################################################
APACHE-HOME/conf/httpd.conf file
####################################################
LoadModule weblogic_module lhome/myhome/weblogic-plugins-12.1.2/lib/mod_wl.so

<Location /weblogic>
 WLSRequest On
 PathTrim /weblogic
 ErrorPage http://myerrorpage1.mydomain.com
</Location>

<Location /servletimages>
 WLSRequest On
 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>

3.4 Deprecated Directives for Apache HTTP Server

The WebLogic Server plug-in logs are now part of the Apache HTTP Server error log and are prefixed with weblogic: to easily identify them. Hence the directives WLLogFile and Debug are deprecated. If the configuration still uses any of these directives, the following note will appear during startup::

The WLLogFile directive is ignored. The web server log file is used instead.The Debug directive is ignored. The web server log level is used instead.

To enable plug-in logs, set LogLevel to debug. The logs will be included in the file pointed to by ErrorLog.