<td><p>Value of secret used by <code class="module"><a href="../mod/mod_proxy_ajp.html">mod_proxy_ajp</a></code>.
See the documentation of this module for more details.</p>
</td></tr>
- <tr><td>upgrade</td>
+ <tr><td><a id="upgrade" name="upgrade">upgrade</a></td>
<td>WebSocket</td>
- <td><p>Protocol accepted in the Upgrade header by <code class="module"><a href="../mod/mod_proxy_wstunnel.html">mod_proxy_wstunnel</a></code>.
- See the documentation of this module for more details.</p>
+ <td><p>Protocol accepted by <code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code> or
+ <code class="module"><a href="../mod/mod_proxy_wstunnel.html">mod_proxy_wstunnel</a></code> for the HTTP Upgrade mechanism
+ upon negotiation by the HTTP client/browser (per
+ <a href="https://www.ietf.org/rfc/rfc9110.html#name-upgrade">RFC 9110 - Upgrade</a>).
+ See the <a href="#protoupgrade">Protocol Upgrade</a> note below</p>
</td></tr>
<tr><td>mapping</td>
<td>-</td>
ProxyPassReverse "/mirror/foo/" "https://backend.example.com/"</pre>
+ <div class="note"><h3><a id="protoupgrade" name="protoupgrade">Protocol Upgrade</a></h3>
+ <p>Since Apache HTTP Server 2.4.47, protocol Upgrade (tunneling) can be handled
+ end-to-end by <code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code> using the <code class="directive">ProxyPass</code>
+ parameter <var><a href="#upgrade">upgrade</a></var>.</p>
+ <p>End-to-end means that the HTTP Upgrade request from the client/browser is first
+ forwarded by <code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code> to the origin server and the connection
+ will be upgraded (and tunneled by <code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code>) only if the origin
+ server accepts/initiates the upgrade (HTTP response <code>101 Switching Protocols</code>).
+ If the origin server responds with anything else <code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code>
+ will continue forwarding (and enforcing) the HTTP protocol as usual for this
+ connection.</p>
+ <div class="example"><h3>Example</h3><pre class="prettyprint lang-config">ProxyPass "/some/http/or/ws/path/" "http://example.com/some/http/or/ws/path/" upgrade=websocket</pre>
+</div>
+ <p>For Apache HTTP Server 2.4.46 and earlier (or if
+ <code class="directive"><a href="../mod/mod_proxy_wstunnel.html#proxywebsocketfallbacktoproxyhttp">ProxyWebsocketFallbackToProxyHttp</a></code>
+ from 2.4.48 and later disables <code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code> handling), see the
+ documentation of <code class="module"><a href="../mod/mod_proxy_wstunnel.html">mod_proxy_wstunnel</a></code> for how to proxy the WebSocket
+ protocol.</p>
+ </div>
+
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="ProxyPassInherit" id="ProxyPassInherit">ProxyPassInherit</a> <a name="proxypassinherit" id="proxypassinherit">Directive</a> <a title="Permanent link" href="#proxypassinherit" class="permalink">¶</a></h2>