Changes to v2.4 APIs.

      <li>Modules that load other modules later than the EXEC_ON_READ config

          reading stage need to call ap_reserve_module_slots() or

          ap_reserve_module_slots_directive() in their pre_config hook.</li>

      <li>The client IP address per request can now be specified independently

          of the peer IP address of the connection for the benefit of load

          balancers</li>

    </ul>

  </section>

      <dt><code>unixd_config</code></dt>

      <dd>This has been renamed to ap_unixd_config.</dd>

      <dt><code>conn_rec->remote_ip and conn_rec->remote_addr</code></dt>

      <dd>In order to distinguish between the peer IP address of the

      connection, and the client IP address of the request potentially

      overridden by a load balancer or proxy, the above variables have

      been renamed. If a module makes reference to either of the above

      variables, they need to be replaced with one of the following two

      options as appropriate for the module:

      <ul>

        <li>When you require the IP address of the client, which might

        be connected directly to the server, or might optionally be

        separated from the server by a transparent load balancer or

        proxy, use request_rec->client_ip and

        request_rec->client_addr.</li>

        <li>When you require the IP address of the peer that is

        connected directly to the server, which might be the client or

        might be the load balancer or proxy itself, use

        conn_rec->peer_ip and conn_rec->peer_addr.</li>

      </ul>

      </dd>

    </dl>

  </section>