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<chapter id="mod_proxy">
  <title>Migration from mod_proxy</title>

  <para>As mod_cluster is a sophisticated balancer migration from mod_proxy to
  mod_cluster is strait forward. mod_cluster replaces a reverse proxy with
  loadbalancing. A reversed proxy is configured like:<programlisting>ProxyRequests Off
&lt;Proxy *&gt;
Order deny,allow
Allow from all
&lt;/Proxy&gt;
ProxyPass /foo http://foo.example.com/bar
ProxyPassReverse /foo http://foo.example.com/bar</programlisting></para>

  <para>All the general proxy parameters could be used in mod_cluster they
  work like in mod_proxy, only the balancers and the workers definitions are
  slightly different.</para>

  <sect1>
    <title>Workers</title>

    <informaltable frame="all">
      <tgroup cols="3">
        <thead>
          <row>
            <entry><para>Mod_proxy Parameter</para></entry>

            <entry><para>ClusterListener parameter</para></entry>

            <entry><para>Remarks</para></entry>
          </row>
        </thead>

        <tbody>
          <row>
            <entry><para>min</para></entry>

            <entry><para>-</para></entry>

            <entry><para>Not supported in this version</para></entry>
          </row>

          <row>
            <entry><para>max</para></entry>

            <entry><para>-</para></entry>

            <entry><para>mod_cluster uses mod_proxy default
            value</para></entry>
          </row>

          <row>
            <entry><para>smax</para></entry>

            <entry><para>smax</para></entry>

            <entry><para>Same as mod_proxy</para></entry>
          </row>

          <row>
            <entry><para>ttl</para></entry>

            <entry><para>ttl</para></entry>

            <entry><para>Same as mod_proxy</para></entry>
          </row>

          <row>
            <entry><para>acquire</para></entry>

            <entry><para>workerTimeout</para></entry>

            <entry><para>Same as mod_proxy acquire but in
            seconds</para></entry>
          </row>

          <row>
            <entry><para>disablereuse</para></entry>

            <entry><para>-</para></entry>

            <entry><para>mod_cluster will disable the node in case of error
            and the ClusterListener will for the reuse via the STATUS
            message</para></entry>
          </row>

          <row>
            <entry><para>flushPackets</para></entry>

            <entry><para>flushPackets</para></entry>

            <entry><para>Same as mod_proxy</para></entry>
          </row>

          <row>
            <entry><para>flushwait</para></entry>

            <entry><para>flushwait</para></entry>

            <entry><para>Same as mod_proxy</para></entry>
          </row>

          <row>
            <entry><para>keepalive</para></entry>

            <entry><para>-</para></entry>

            <entry><para>Always on: OS KEEP_ALIVE is always used. Use
            connectionTimeout in the &lt;Connector&gt; if
            needed</para></entry>
          </row>

          <row>
            <entry><para>lbset</para></entry>

            <entry><para>-</para></entry>

            <entry><para>Not supported</para></entry>
          </row>

          <row>
            <entry><para>ping</para></entry>

            <entry><para>ping</para></entry>

            <entry><para>Same as mod_proxy Default value 10
            seconds</para></entry>
          </row>

          <row>
            <entry><para>lbfactor</para></entry>

            <entry><para>-</para></entry>

            <entry><para>The load factor is received by mod_cluster from a
            calculated value in the ClusterListener</para></entry>
          </row>

          <row>
            <entry><para>redirect</para></entry>

            <entry><para>-</para></entry>

            <entry><para>Not supported lbfactor sent to 0 makes a standby
            node</para></entry>
          </row>

          <row>
            <entry><para>retry</para></entry>

            <entry><para>-</para></entry>

            <entry><para>ClusterListener will test when the node is back
            online</para></entry>
          </row>

          <row>
            <entry><para>route</para></entry>

            <entry><para>JVMRoute</para></entry>

            <entry><para>In fact JBossWEB via the JVMRoute in the Engine will
            add it</para></entry>
          </row>

          <row>
            <entry><para>status</para></entry>

            <entry><para>-</para></entry>

            <entry><para>mod_cluster has a finer status handling: by context
            via the ENABLE/STOP/DISABLE/REMOVE application messages.
            hot-standby is done by lbfactor = 0 and Error by lbfactor = 1 both
            values are sent in STATUS message by the
            ClusterListener</para></entry>
          </row>

          <row>
            <entry><para>timeout</para></entry>

            <entry><para>nodeTimeout</para></entry>

            <entry><para>Default wait for ever
            (http://httpd.apache.org/docs/2.2/mod/mod_proxy.html is wrong
            there)</para></entry>
          </row>

          <row>
            <entry><para>ttl</para></entry>

            <entry><para>ttl</para></entry>

            <entry><para>Default 60 seconds</para></entry>
          </row>
        </tbody>
      </tgroup>
    </informaltable>
  </sect1>

  <sect1>
    <title>Balancers</title>

    <informaltable frame="all">
      <tgroup cols="3">
        <thead>
          <row>
            <entry><para>Mod_proxy Parameter</para></entry>

            <entry><para>ClusterListener parameter</para></entry>

            <entry><para>Remarks</para></entry>
          </row>
        </thead>

        <tbody>
          <row>
            <entry><para>lbmethod</para></entry>

            <entry><para>-</para></entry>

            <entry><para>There is only one load balancing method in
            mod_cluster "cluster_byrequests"</para></entry>
          </row>

          <row>
            <entry><para>maxattempts</para></entry>

            <entry><para>maxAttempts</para></entry>

            <entry><para>Default 1</para></entry>
          </row>

          <row>
            <entry><para>nofailover</para></entry>

            <entry><para>stickySessionForce</para></entry>

            <entry><para>Same as in mod_proxy</para></entry>
          </row>

          <row>
            <entry><para>stickysession</para></entry>

            <entry><para>StickySessionCookie/StickySessionPath</para></entry>

            <entry><para>The 2 parameters in the ClusterListener are combined
            in one that behaves like in mod_proxy</para></entry>
          </row>

          <row>
            <entry><para>timeout</para></entry>

            <entry><para>workerTimeout</para></entry>

            <entry><para>Default 1 seconds</para></entry>
          </row>
        </tbody>
      </tgroup>
    </informaltable>

    <para></para>
  </sect1>
</chapter>
