ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent<?xml version="1.0"?>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent<!DOCTYPE modulesynopsis SYSTEM "/style/modulesynopsis.dtd">

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent<?xml-stylesheet type="text/xsl" href="/style/manual.en.xsl"?>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent<modulesynopsis metafile="mod_proxy_http.xml.meta">

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent<name>mod_proxy_http</name>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent<description>HTTP support module for

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent<module>mod_proxy</module></description>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent<status>Extension</status>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent<sourcefile>mod_proxy_http.c</sourcefile>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent<identifier>proxy_http_module</identifier>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent<summary>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <p>This module <em>requires</em> the service of <module

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent >mod_proxy</module>. It provides the features used for

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent proxying HTTP and HTTPS requests. <module>mod_proxy_http</module>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent supports HTTP/0.9, HTTP/1.0 and HTTP/1.1. It does <em>not</em>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent provide any caching abilities. If you want to set up a caching

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent proxy, you might want to use the additional service of the

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <module>mod_cache</module> module.</p>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <p>Thus, in order to get the ability of handling HTTP proxy requests,

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <module>mod_proxy</module> and <module>mod_proxy_http</module>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent have to be present in the server.</p>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <note type="warning"><title>Warning</title>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <p>Do not enable proxying until you have <a

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent href="mod_proxy.html#access">secured your server</a>. Open proxy

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent servers are dangerous both to your network and to the Internet at

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent large.</p>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent </note>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent</summary>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent<seealso><module>mod_proxy</module></seealso>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent<seealso><module>mod_proxy_connect</module></seealso>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent<section id="env"><title>Environment Variables</title>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <p>In addition to the configuration directives that control the

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent behaviour of <module>mod_proxy</module>, there are a number of

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dfn>environment variables</dfn> that control the HTTP protocol

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent provider. Environment variables below that don't specify specific values

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent are enabled when set to any value.</p>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dl>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dt>proxy-sendextracrlf</dt>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dd>Causes proxy to send an extra CR-LF newline on the end of a

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent request. This is a workaround for a bug in some browsers.</dd>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dt>force-proxy-request-1.0</dt>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dd>Forces the proxy to send requests to the backend as HTTP/1.0

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent and disables HTTP/1.1 features.</dd>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dt>proxy-nokeepalive</dt>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dd>Forces the proxy to close the backend connection after

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent each request.</dd>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dt>proxy-chain-auth</dt>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dd>If the proxy requires authentication, it will read and

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent consume the proxy authentication credentials sent by the client.

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent With <var>proxy-chain-auth</var> it will <em>also</em> forward

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent the credentials to the next proxy in the chain. This may

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent be necessary if you have a chain of proxies that share

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent authentication information. <strong>Security Warning:</strong>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent Do not set this unless you know you need it, as it forwards

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent sensitive information!</dd>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dt>proxy-sendcl</dt>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dd>HTTP/1.0 required all HTTP requests that include a body

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent (e.g. POST requests) to include a <var>Content-Length</var>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent header. This environment variable forces the Apache proxy to

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent send this header to the backend server, regardless of what the

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent Client sent to the proxy. It ensures compatibility when

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent proxying for an HTTP/1.0 or unknown backend. However, it

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent may require the entire request to be buffered by the proxy,

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent so it becomes very inefficient for large requests.</dd>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dt>proxy-sendchunks or proxy-sendchunked</dt>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dd>This is the opposite of <var>proxy-sendcl</var>. It allows

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent request bodies to be sent to the backend using chunked transfer

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent encoding. This allows the request to be efficiently streamed,

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent but requires that the backend server supports HTTP/1.1.</dd>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dt>proxy-interim-response</dt>

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <dd>This variable takes values <code>RFC</code> (the default) or

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent <code>Suppress</code>. Earlier httpd versions would suppress

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent HTTP interim (1xx) responses sent from the backend. This is

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent technically a violation of the HTTP protocol. In practice,

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent if a backend sends an interim response, it may itself be

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent extending the protocol in a manner we know nothing about,

ac0d91b16ffcc7d2e0adc288dfc92e58728a27ebjason vincent or just broken. So this is now configurable: set

<code>proxy-interim-response RFC</code> to be fully protocol

compliant, or <code>proxy-interim-response Suppress</code>

to suppress interim responses.</dd>

<dt>proxy-initial-not-pooled</dt>

<dd>If this variable is set, no pooled connection will be reused

if the client request is the initial request on the frontend connection. This avoids

the "proxy: error reading status line from remote server" error message

caused by the race condition that the backend server closed the

pooled connection after the connection check by the proxy and

before data sent by the proxy reached the backend. It has to be

kept in mind that setting this variable downgrades performance,

especially with HTTP/1.0 clients.

</dd>

</dl>

</section>

<section id="notes"><title>Request notes</title>

<p><module>mod_proxy_http</module> creates the following request notes for

logging using the <code>%{VARNAME}n</code> format in

<directive module="mod_log_config">LogFormat</directive> or

<directive module="core">ErrorLogFormat</directive>:

</p>

<dl>

<dt>proxy-source-port</dt>

<dd>The local port used for the connection to the backend server.</dd>

<dt>proxy-status</dt>

<dd>The HTTP status received from the backend server.</dd>

</dl>

</section>

</modulesynopsis>