######################################################
# This document was kindly contributed by Larry
# Lansing (lansil @ fuzzynerd.com).  For any questions
# regarding this information, please contact him
# directly.
######################################################

As promised, here are my loadbalancing configuration files.  These are
still works-in-progress--there are probably mistakes and omissions.  I
hope someone finds these useful.

Notes: The apache server (I'll call it "www") relays connections to
two tomcat servers called "jsp1" and "jsp2", using ajp13.  www runs
Apache2.0, with mod_jk.  jsp1 and jsp2 run Tomcat 4.1.24.  I have
tried to simplify my configs by disabling unnecessary tomcat
connectors, such as the standalone port 8080 HTTP connector.

www configs
-----------
httpd.conf must include these lines in appropriate places:
***
LoadModule jk_module libexec/apache2/mod_jk.so
Include /usr/local/etc/apache2/mod_jk.conf
***

mod_jk.conf:
***

<IfModule mod_jk.c>
        JkWorkersFile /usr/local/etc/apache2/workers.properties
        JkLogFile  logs/jk.log
        JkLogLevel warn
        JkMount /dspace/* loadbalancer
        JkMount /dspace-oai/* loadbalancer
</IfModule>
***

workers_properties:
***
worker.list=loadbalancer

worker.jsp1.port=8009
worker.jsp1.host=jsp1
worker.jsp1.type=ajp13
worker.jsp1.lbfactor=1

worker.jsp2.port=8009
worker.jsp2.host=jsp2
worker.jsp2.type=ajp13
worker.jsp2.lbfactor=1

worker.loadbalancer.type=lb
worker.loadbalancer.balanced_workers=jsp1, jsp2
***

jsp1 and jsp2
-------------
Tomcat's server.xml (still a bit "raw" until I figure out what each
option does):
***

<!-- Larry's simple DSpace tomcat config. -->
<Server port="8005" shutdown="SHUTDOWN" debug="0">

  <!-- Define the Tomcat Stand-Alone Service -->
  <Service name="Tomcat-Standalone">

    <!-- Define an AJP 1.3 Connector on port 8009 -->
    <Connector className="org.apache.ajp.tomcat4.Ajp13Connector"
               port="8009" minProcessors="5" maxProcessors="75"
               acceptCount="10" debug="0"/>

    <!-- Define the top level container in our container hierarchy -->
    <Engine name="Standalone" defaultHost="localhost" debug="0">

      <!-- Global logger unless overridden at lower levels -->
      <Logger className="org.apache.catalina.logger.FileLogger"
              prefix="catalina_log." suffix=".txt"
              timestamp="true"/>

      <!-- Because this Realm is here, an instance will be shared globally -->
      <Realm className="org.apache.catalina.realm.MemoryRealm" />

      <!-- Define the default virtual host -->
      <Host name="localhost" debug="0" appBase="webapps" 
       unpackWARs="true" autoDeploy="true">

        <!-- Access log processes all requests for this virtual host.  By
             default, log files are created in the "logs" directory relative to
             $CATALINA_HOME.  If you wish, you can specify a different
             directory with the "directory" attribute.  Specify either a relative
             (to $CATALINA_HOME) or absolute path to the desired directory.
        -->
        <Valve className="org.apache.catalina.valves.AccessLogValve"
                 directory="logs"  prefix="localhost_access_log." suffix=".txt"
                 pattern="common"/>

        <!-- Logger shared by all Contexts related to this virtual host.  By
             default (when using FileLogger), log files are created in the "logs"
             directory relative to $CATALINA_HOME.  If you wish, you can specify
             a different directory with the "directory" attribute.  Specify either a
             relative (to $CATALINA_HOME) or absolute path to the desired
             directory.-->
        <Logger className="org.apache.catalina.logger.FileLogger"
                 directory="logs"  prefix="localhost_log." suffix=".txt"
                timestamp="true"/>

        <!-- Define properties for each web application.  This is only needed
             if you want to set non-default properties, or have web application
             document roots in places other than the virtual host's appBase
             directory.  -->

        <!-- Contexts -->
          <Context path="/dspace" docBase="dspace" debug="0">
            <Resources className="org.apache.naming.resources.FileDirContext"
                allowLinking="true" docBase="" />
          </Context>
          <Context path="/dspace-oai" docBase="dspace-oai" debug="0">
            <Resources className="org.apache.naming.resources.FileDirContext"
                allowLinking="true" docBase="" />
          </Context>

      </Host>

    </Engine>

  </Service>

</Server>
***