This section explains how to set up the Apache server with the JK Connector (mod_jk) module for load balancing.

1. Download and install the JK Connector from http://www.apache.org/dist/tomcat/tomcat-connectors/jk/.
2. We recommend downloading the source code and building the connector based on the instructions in BUILD.txt:

   $ cd native
   $ ./configure --with-apxs={APACHE_HOME}/bin/apxs
   $ make
   $ make install
   

3. Add the following at the end of the APACHE_HOME\conf\httpd.conf file:

   # Include mod_jk's specific configuration file
   Include conf/mod-jk.conf
   

4. Create a new file named APACHE_HOME\conf\mod-jk.conf with the following:

   # Load mod_jk module
   # Specify the filename of the mod_jk lib
   LoadModule jk_module modules/mod_jk.so
   
   # Where to find workers.properties
   JkWorkersFile conf/workers.properties
   
   # Where to put jk logs
   JkLogFile logs/mod_jk.log
   
   # Set the jk log level [PD:debug/error/info]
   JkLogLevel info
   
   # Select the log format
   JkLogStampFormat  "[%a %b %d %H:%M:%S %Y]"
   
   # JkOptions indicates to send SSK KEY SIZE
   JkOptions +ForwardKeySize +ForwardURICompat -ForwardDirectories
   
   # JkRequestLogFormat
   JkRequestLogFormat "%w %V %T"
   
   # Mount your applications
   JkMount /* loadbalancer
   
   # You can use external file for mount points.
   # It will be checked for updates each 60 seconds.
   # The format of the file is: /url=worker
   # /examples/*=loadbalancer
   JkMountFile conf/uriworkermap.properties
   
   # Add shared memory.
   # This directive is present with 1.2.10 and
   # later versions of mod_jk, and is needed for
   # for load balancing to work properly
   JkShmFile logs/jk.shm
   
   # Add jkstatus for managing runtime data
   <Location /jkstatus/>
       JkMount status
       Order deny,allow
       Deny from all
       Allow from 127.0.0.1
   </Location>
   

5. Create a new file named APACHE_HOME\conf\workers.properties with the following lines. Replace SF1_SERVER_IP and SF2_SERVER_IP with the IP addresses of the servers that will be the nodes in the cluster.

   # Define list of workers that will be used
   # for mapping requests
   worker.list=loadbalancer,status
   
   # Define Node1
   # modify the host as your host IP or DNS name.
   worker.node1.port=8009
   worker.node1.host={SF1_SERVER_IP}
   worker.node1.type=ajp13
   worker.node1.lbfactor=1
   worker.node1.cachesize=100
   
   # Define Node2
   # modify the host as your host IP or DNS name.
   worker.node2.port=8009
   worker.node2.host={SF2_SERVER_IP}
   worker.node2.type=ajp13
   worker.node2.lbfactor=1
   worker.node2.cachesize=100
   
   # Load-balancing behaviour
   worker.loadbalancer.type=lb
   worker.loadbalancer.balance_workers=node1,node2
   worker.loadbalancer.sticky_session=1
   
   # Status worker for managing load balancer
   worker.status.type=status
   

For more information on the JK Connector, see http://tomcat.apache.org/connectors-doc/index.html.