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|
<?xml version="1.0" encoding="ISO-8859-1"?>
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<title>mod_proxy - Apache HTTP Server</title>
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<p class="apache">Apache HTTP Server Version 2.0</p>
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<a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs/">Documentation</a> > <a href="../">Version 2.0</a> > <a href="./">Modules</a></div>
<div id="page-content">
<div id="preamble"><h1>Apache Module mod_proxy</h1>
<div class="toplang">
<p><span>Available Languages: </span><a href="../en/mod/mod_proxy.html" title="English"> en </a></p>
</div>
<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>HTTP/1.1 proxy/gateway server</td></tr>
<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="module-dict.html#ModuleIdentifier">Module�Identifier:</a></th><td>proxy_module</td></tr>
<tr><th><a href="module-dict.html#SourceFile">Source�File:</a></th><td>mod_proxy.c</td></tr></table>
<h3>Summary</h3>
<div class="warning"><h3>Warning</h3>
<p>Do not enable proxying with <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> until you have <a href="#access">secured your server</a>. Open proxy servers are dangerous both to your
network and to the Internet at large.</p>
</div>
<p>This module implements a proxy/gateway for Apache. It implements
proxying capability for <code>FTP</code>, <code>CONNECT</code> (for SSL),
<code>HTTP/0.9</code>, <code>HTTP/1.0</code>, and <code>HTTP/1.1</code>.
The module can be configured to connect to other proxy modules for these
and other protocols.</p>
<p>Apache's proxy features are divided into several modules in
addition to <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>:
<code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code>, <code class="module"><a href="../mod/mod_proxy_ftp.html">mod_proxy_ftp</a></code>
and <code class="module"><a href="../mod/mod_proxy_connect.html">mod_proxy_connect</a></code>. Thus, if you want to use
one or more of the particular proxy functions, load
<code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> <em>and</em> the appropriate module(s)
into the server (either statically at compile-time or dynamically
via the <code class="directive"><a href="../mod/mod_so.html#loadmodule">LoadModule</a></code>
directive).</p>
<p>In addition, extended features are provided by other modules.
Caching is provided by <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code> and related
modules. The ability to contact remote servers using the SSL/TLS
protocol is provided by the <code>SSLProxy*</code> directives of
<code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code>. These additional modules will need
to be loaded and configured to take advantage of these features.</p>
</div>
<div id="quickview"><h3 class="directives">Directives</h3>
<ul id="toc">
<li><img alt="" src="../images/down.gif" /> <a href="#allowconnect">AllowCONNECT</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#noproxy">NoProxy</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxy"><Proxy></a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxybadheader">ProxyBadHeader</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxyblock">ProxyBlock</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxydomain">ProxyDomain</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxyerroroverride">ProxyErrorOverride</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxyftpdircharset">ProxyFtpDirCharset</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxyiobuffersize">ProxyIOBufferSize</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxymatch"><ProxyMatch></a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxymaxforwards">ProxyMaxForwards</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxypass">ProxyPass</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxypassreverse">ProxyPassReverse</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxypreservehost">ProxyPreserveHost</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxyreceivebuffersize">ProxyReceiveBufferSize</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxyremote">ProxyRemote</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxyremotematch">ProxyRemoteMatch</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxyrequests">ProxyRequests</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxytimeout">ProxyTimeout</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#proxyvia">ProxyVia</a></li>
</ul>
<h3>Topics</h3>
<ul id="topics">
<li><img alt="" src="../images/down.gif" /> <a href="#forwardreverse">Forward and Reverse Proxies</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#examples">Basic Examples</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#access">Controlling access to your proxy</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#ftp-proxy">FTP Proxy</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#startup">Slow Startup</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#intranet">Intranet Proxy</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#envsettings">Protocol Adjustments</a></li>
</ul><h3>See also</h3>
<ul class="seealso">
<li><code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code></li>
<li><code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code></li>
<li><code class="module"><a href="../mod/mod_proxy_ftp.html">mod_proxy_ftp</a></code></li>
<li><code class="module"><a href="../mod/mod_proxy_connect.html">mod_proxy_connect</a></code></li>
<li><code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code></li>
</ul></div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="forwardreverse" id="forwardreverse">Forward and Reverse Proxies</a></h2>
<p>Apache can be configured in both a <dfn>forward</dfn> and
<dfn>reverse</dfn> proxy mode.</p>
<p>An ordinary <dfn>forward proxy</dfn> is an intermediate
server that sits between the client and the <em>origin
server</em>. In order to get content from the origin server,
the client sends a request to the proxy naming the origin server
as the target and the proxy then requests the content from the
origin server and returns it to the client. The client must be
specially configured to use the forward proxy to access other
sites.</p>
<p>A typical usage of a forward proxy is to provide Internet
access to internal clients that are otherwise restricted by a
firewall. The forward proxy can also use caching (as provided
by <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code>) to reduce network usage.</p>
<p>The forward proxy is activated using the <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive. Because
forward proxys allow clients to access arbitrary sites through
your server and to hide their true origin, it is essential that
you <a href="#access">secure your server</a> so that only
authorized clients can access the proxy before activating a
forward proxy.</p>
<p>A <dfn>reverse proxy</dfn>, by contrast, appears to the
client just like an ordinary web server. No special
configuration on the client is necessary. The client makes
ordinary requests for content in the name-space of the reverse
proxy. The reverse proxy then decides where to send those
requests, and returns the content as if it was itself the
origin.</p>
<p>A typical usage of a reverse proxy is to provide Internet
users access to a server that is behind a firewall. Reverse
proxies can also be used to balance load among several back-end
servers, or to provide caching for a slower back-end server.
In addition, reverse proxies can be used simply to bring
several servers into the same URL space.</p>
<p>A reverse proxy is activated using the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive or the
<code>[P]</code> flag to the <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> directive. It is
<strong>not</strong> necessary to turn <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> on in order to
configure a reverse proxy.</p>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="examples" id="examples">Basic Examples</a></h2>
<p>The examples below are only a very basic idea to help you
get started. Please read the documentation on the individual
directives.</p>
<p>In addition, if you wish to have caching enabled, consult
the documentation from <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code>.</p>
<div class="example"><h3>Forward Proxy</h3><p><code>
ProxyRequests On<br />
ProxyVia On<br />
<br />
<Proxy *><br />
<span class="indent">
Order deny,allow<br />
Deny from all<br />
Allow from internal.example.com<br />
</span>
</Proxy>
</code></p></div>
<div class="example"><h3>Reverse Proxy</h3><p><code>
ProxyRequests Off<br />
<br />
<Proxy *><br />
<span class="indent">
Order deny,allow<br />
Allow from all<br />
</span>
</Proxy><br />
<br />
ProxyPass /foo http://foo.example.com/bar<br />
ProxyPassReverse /foo http://foo.example.com/bar
</code></p></div>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="access" id="access">Controlling access to your proxy</a></h2>
<p>You can control who can access your proxy via the <code class="directive"><a href="#proxy"><Proxy></a></code> control block as in
the following example:</p>
<div class="example"><p><code>
<Proxy *><br />
<span class="indent">
Order Deny,Allow<br />
Deny from all<br />
Allow from 192.168.0<br />
</span>
</Proxy>
</code></p></div>
<p>For more information on access control directives, see
<code class="module"><a href="../mod/mod_access.html">mod_access</a></code>.</p>
<p>Strictly limiting access is essential if you are using a
forward proxy (using the <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive).
Otherwise, your server can be used by any client to access
arbitrary hosts while hiding his or her true identity. This is
dangerous both for your network and for the Internet at large.
When using a reverse proxy (using the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive with
<code>ProxyRequests Off</code>), access control is less
critical because clients can only contact the hosts that you
have specifically configured.</p>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="ftp-proxy" id="ftp-proxy">FTP Proxy</a></h2>
<h3><a name="mimetypes" id="mimetypes">Why doesn't file type <var>xxx</var>
download via FTP?</a></h3>
<p>You probably don't have that particular file type defined as
<code>application/octet-stream</code> in your proxy's mime.types
configuration file. A useful line can be</p>
<div class="example"><pre>application/octet-stream bin dms lha lzh exe class tgz taz</pre></div>
<h3><a name="type" id="type">How can I force an FTP ASCII download of
File <var>xxx</var>?</a></h3>
<p>In the rare situation where you must download a specific file using the
FTP <code>ASCII</code> transfer method (while the default transfer is in
<code>binary</code> mode), you can override <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>'s
default by suffixing the request with <code>;type=a</code> to force an
ASCII transfer. (FTP Directory listings are always executed in ASCII mode,
however.)</p>
<h3><a name="percent2fhck" id="percent2fhck">How can I access FTP files outside
of my home directory?</a></h3>
<p>An FTP URI is interpreted relative to the home directory of the user
who is logging in. Alas, to reach higher directory levels you cannot
use /../, as the dots are interpreted by the browser and not actually
sent to the FTP server. To address this problem, the so called <dfn>Squid
%2f hack</dfn> was implemented in the Apache FTP proxy; it is a
solution which is also used by other popular proxy servers like the <a href="http://www.squid-cache.org/">Squid Proxy Cache</a>. By
prepending <code>/%2f</code> to the path of your request, you can make
such a proxy change the FTP starting directory to <code>/</code> (instead
of the home directory). For example, to retrieve the file
<code>/etc/motd</code>, you would use the URL:</p>
<div class="example"><p><code>
ftp://<var>user</var>@<var>host</var>/%2f/etc/motd
</code></p></div>
<h3><a name="ftppass" id="ftppass">How can I hide the FTP cleartext password
in my browser's URL line?</a></h3>
<p>To log in to an FTP server by username and password, Apache uses
different strategies. In absense of a user name and password in the URL
altogether, Apache sends an anonymous login to the FTP server,
<em>i.e.</em>,</p>
<div class="example"><p><code>
user: anonymous<br />
password: apache_proxy@
</code></p></div>
<p>This works for all popular FTP servers which are configured for
anonymous access.</p>
<p>For a personal login with a specific username, you can embed the user
name into the URL, like in:</p>
<div class="example"><p><code>
ftp://<var>username</var>@<var>host</var>/myfile
</code></p></div>
<p>If the FTP server asks for a password when given this username (which
it should), then Apache will reply with a <code>401</code> (Authorization
required) response, which causes the Browser to pop up the
username/password dialog. Upon entering the password, the connection
attempt is retried, and if successful, the requested resource is
presented. The advantage of this procedure is that your browser does not
display the password in cleartext (which it would if you had used</p>
<div class="example"><p><code>
ftp://<var>username</var>:<var>password</var>@<var>host</var>/myfile
</code></p></div>
<p>in the first place).</p>
<div class="note"><h3>Note</h3>
<p>The password which is transmitted in such a way is not encrypted on
its way. It travels between your browser and the Apache proxy server in
a base64-encoded cleartext string, and between the Apache proxy and the
FTP server as plaintext. You should therefore think twice before
accessing your FTP server via HTTP (or before accessing your personal
files via FTP at all!) When using unsecure channels, an eavesdropper
might intercept your password on its way.</p>
</div>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="startup" id="startup">Slow Startup</a></h2>
<p>If you're using the <code class="directive"><a href="#proxyblock">ProxyBlock</a></code> directive, hostnames' IP addresses are looked up
and cached during startup for later match test. This may take a few
seconds (or more) depending on the speed with which the hostname lookups
occur.</p>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="intranet" id="intranet">Intranet Proxy</a></h2>
<p>An Apache proxy server situated in an intranet needs to forward
external requests through the company's firewall (for this, configure
the <code class="directive"><a href="#proxyremote">ProxyRemote</a></code> directive
to forward the respective <var>scheme</var> to the firewall proxy).
However, when it has to
access resources within the intranet, it can bypass the firewall when
accessing hosts. The <code class="directive"><a href="#noproxy">NoProxy</a></code>
directive is useful for specifying which hosts belong to the intranet and
should be accessed directly.</p>
<p>Users within an intranet tend to omit the local domain name from their
WWW requests, thus requesting "http://somehost/" instead of
<code>http://somehost.example.com/</code>. Some commercial proxy servers
let them get away with this and simply serve the request, implying a
configured local domain. When the <code class="directive"><a href="#proxydomain">ProxyDomain</a></code> directive is used and the server is <a href="#proxyrequests">configured for proxy service</a>, Apache can return
a redirect response and send the client to the correct, fully qualified,
server address. This is the preferred method since the user's bookmark
files will then contain fully qualified hosts.</p>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="envsettings" id="envsettings">Protocol Adjustments</a></h2>
<p>For circumstances where you have a application server which doesn't
implement keepalives or HTTP/1.1 properly, there are 2 environment
variables which when set send a HTTP/1.0 with no keepalive. These are set
via the <code class="directive"><a href="../mod/mod_env.html#setenv">SetEnv</a></code> directive.</p>
<p>These are the <code>force-proxy-request-1.0</code> and
<code>proxy-nokeepalive</code> notes.</p>
<div class="example"><p><code>
<Location /buggyappserver/><br />
<span class="indent">
ProxyPass http://buggyappserver:7001/foo/<br />
SetEnv force-proxy-request-1.0 1<br />
SetEnv proxy-nokeepalive 1<br />
</span>
</Location>
</code></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="AllowCONNECT" id="AllowCONNECT">AllowCONNECT</a> <a name="allowconnect" id="allowconnect">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Ports that are allowed to <code>CONNECT</code> through the
proxy</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AllowCONNECT <var>port</var> [<var>port</var>] ...</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AllowCONNECT 443 563</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
</table>
<p>The <code class="directive">AllowCONNECT</code> directive specifies a list
of port numbers to which the proxy <code>CONNECT</code> method may
connect. Today's browsers use this method when a <code>https</code>
connection is requested and proxy tunneling over HTTP is in effect.</p>
<p>By default, only the default https port (<code>443</code>) and the
default snews port (<code>563</code>) are enabled. Use the
<code class="directive">AllowCONNECT</code> directive to override this default and
allow connections to the listed ports only.</p>
<p>Note that you'll need to have <code class="module"><a href="../mod/mod_proxy_connect.html">mod_proxy_connect</a></code> present
in the server in order to get the support for the <code>CONNECT</code> at
all.</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="NoProxy" id="NoProxy">NoProxy</a> <a name="noproxy" id="noproxy">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Hosts, domains, or networks that will be connected to
directly</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>NoProxy <var>host</var> [<var>host</var>] ...</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
</table>
<p>This directive is only useful for Apache proxy servers within
intranets. The <code class="directive">NoProxy</code> directive specifies a
list of subnets, IP addresses, hosts and/or domains, separated by
spaces. A request to a host which matches one or more of these is
always served directly, without forwarding to the configured
<code class="directive"><a href="#proxyremote">ProxyRemote</a></code> proxy server(s).</p>
<div class="example"><h3>Example</h3><p><code>
ProxyRemote * http://firewall.mycompany.com:81<br />
NoProxy .mycompany.com 192.168.112.0/21
</code></p></div>
<p>The <var>host</var> arguments to the <code class="directive">NoProxy</code>
directive are one of the following type list:</p>
<dl>
<dt><var><a name="domain" id="domain">Domain</a></var></dt>
<dd>
<p>A <dfn>Domain</dfn> is a partially qualified DNS domain name, preceded
by a period. It represents a list of hosts which logically belong to the
same DNS domain or zone (<em>i.e.</em>, the suffixes of the hostnames are
all ending in <var>Domain</var>).</p>
<div class="example"><h3>Examples</h3><p><code>
.com .apache.org.
</code></p></div>
<p>To distinguish <var>Domain</var>s from <var><a href="#hostname">Hostname</a></var>s (both syntactically and semantically; a DNS domain can
have a DNS A record, too!), <var>Domain</var>s are always written with a
leading period.</p>
<div class="note"><h3>Note</h3>
<p>Domain name comparisons are done without regard to the case, and
<var>Domain</var>s are always assumed to be anchored in the root of the
DNS tree, therefore two domains <code>.MyDomain.com</code> and
<code>.mydomain.com.</code> (note the trailing period) are considered
equal. Since a domain comparison does not involve a DNS lookup, it is much
more efficient than subnet comparison.</p>
</div></dd>
<dt><var><a name="subnet" id="subnet">SubNet</a></var></dt>
<dd>
<p>A <dfn>SubNet</dfn> is a partially qualified internet address in
numeric (dotted quad) form, optionally followed by a slash and the netmask,
specified as the number of significant bits in the <var>SubNet</var>. It is
used to represent a subnet of hosts which can be reached over a common
network interface. In the absence of the explicit net mask it is assumed
that omitted (or zero valued) trailing digits specify the mask. (In this
case, the netmask can only be multiples of 8 bits wide.) Examples:</p>
<dl>
<dt><code>192.168</code> or <code>192.168.0.0</code></dt>
<dd>the subnet 192.168.0.0 with an implied netmask of 16 valid bits
(sometimes used in the netmask form <code>255.255.0.0</code>)</dd>
<dt><code>192.168.112.0/21</code></dt>
<dd>the subnet <code>192.168.112.0/21</code> with a netmask of 21
valid bits (also used in the form 255.255.248.0)</dd>
</dl>
<p>As a degenerate case, a <em>SubNet</em> with 32 valid bits is the
equivalent to an <var><a href="#ipadr">IPAddr</a></var>, while a <var>SubNet</var> with zero
valid bits (<em>e.g.</em>, 0.0.0.0/0) is the same as the constant
<var>_Default_</var>, matching any IP address.</p></dd>
<dt><var><a name="ipaddr" id="ipaddr">IPAddr</a></var></dt>
<dd>
<p>A <dfn>IPAddr</dfn> represents a fully qualified internet address in
numeric (dotted quad) form. Usually, this address represents a host, but
there need not necessarily be a DNS domain name connected with the
address.</p>
<div class="example"><h3>Example</h3><p><code>
192.168.123.7
</code></p></div>
<div class="note"><h3>Note</h3>
<p>An <var>IPAddr</var> does not need to be resolved by the DNS system, so
it can result in more effective apache performance.</p>
</div></dd>
<dt><var><a name="hostname" id="hostname">Hostname</a></var></dt>
<dd>
<p>A <dfn>Hostname</dfn> is a fully qualified DNS domain name which can
be resolved to one or more <var><a href="#ipaddr">IPAddrs</a></var> via the
DNS domain name service. It represents a logical host (in contrast to
<var><a href="#domain">Domain</a></var>s, see above) and must be resolvable
to at least one <var><a href="#ipaddr">IPAddr</a></var> (or often to a list
of hosts with different <var><a href="#ipaddr">IPAddr</a></var>s).</p>
<div class="example"><h3>Examples</h3><p><code>
prep.ai.mit.edu<br />
www.apache.org
</code></p></div>
<div class="note"><h3>Note</h3>
<p>In many situations, it is more effective to specify an <var><a href="#ipaddr">IPAddr</a></var> in place of a <var>Hostname</var> since a
DNS lookup can be avoided. Name resolution in Apache can take a remarkable
deal of time when the connection to the name server uses a slow PPP
link.</p>
<p><var>Hostname</var> comparisons are done without regard to the case,
and <var>Hostname</var>s are always assumed to be anchored in the root
of the DNS tree, therefore two hosts <code>WWW.MyDomain.com</code>
and <code>www.mydomain.com.</code> (note the trailing period) are
considered equal.</p>
</div></dd>
</dl>
<h3>See also</h3>
<ul>
<li><a href="../dns-caveats.html">DNS Issues</a></li>
</ul>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="Proxy" id="Proxy"><Proxy></a> <a name="proxy" id="proxy">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Container for directives applied to proxied resources</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Proxy <var>wildcard-url</var>> ...</Proxy></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
</table>
<p>Directives placed in <code class="directive"><Proxy></code>
sections apply only to matching proxied content. Shell-style wildcards are
allowed.</p>
<p>For example, the following will allow only hosts in
<code>yournetwork.example.com</code> to access content via your proxy
server:</p>
<div class="example"><p><code>
<Proxy *><br />
<span class="indent">
Order Deny,Allow<br />
Deny from all<br />
Allow from yournetwork.example.com<br />
</span>
</Proxy>
</code></p></div>
<p>The following example will process all files in the <code>foo</code>
directory of <code>example.com</code> through the <code>INCLUDES</code>
filter when they are sent through the proxy server:</p>
<div class="example"><p><code>
<Proxy http://example.com/foo/*><br />
<span class="indent">
SetOutputFilter INCLUDES<br />
</span>
</Proxy>
</code></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="ProxyBadHeader" id="ProxyBadHeader">ProxyBadHeader</a> <a name="proxybadheader" id="proxybadheader">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determines how to handle bad header lines in a
response</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyBadHeader IsError|Ignore|StartBody</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyBadHeader IsError</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.44 and later</td></tr>
</table>
<p>The <code class="directive">ProxyBadHeader</code> directive determines the
behaviour of <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> if it receives syntactically invalid
header lines (<em>i.e.</em> containing no colon). The following arguments
are possible:</p>
<dl>
<dt><code>IsError</code></dt>
<dd>Abort the request and end up with a 502 (Bad Gateway) response. This is
the default behaviour.</dd>
<dt><code>Ignore</code></dt>
<dd>Treat bad header lines as if they weren't sent.</dd>
<dt><code>StartBody</code></dt>
<dd>When receiving the first bad header line, finish reading the headers and
treat the remainder as body. This helps to work around buggy backend servers
which forget to insert an empty line between the headers and the body.</dd>
</dl>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="ProxyBlock" id="ProxyBlock">ProxyBlock</a> <a name="proxyblock" id="proxyblock">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Words, hosts, or domains that are banned from being
proxied</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyBlock *|<var>word</var>|<var>host</var>|<var>domain</var>
[<var>word</var>|<var>host</var>|<var>domain</var>] ...</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
</table>
<p>The <code class="directive">ProxyBlock</code> directive specifies a list of
words, hosts and/or domains, separated by spaces. HTTP, HTTPS, and
FTP document requests to sites whose names contain matched words,
hosts or domains are <em>blocked</em> by the proxy server. The proxy
module will also attempt to determine IP addresses of list items which
may be hostnames during startup, and cache them for match test as
well. That may slow down the startup time of the server.</p>
<div class="example"><h3>Example</h3><p><code>
ProxyBlock joes-garage.com some-host.co.uk rocky.wotsamattau.edu
</code></p></div>
<p><code>rocky.wotsamattau.edu</code> would also be matched if referenced by
IP address.</p>
<p>Note that <code>wotsamattau</code> would also be sufficient to match
<code>wotsamattau.edu</code>.</p>
<p>Note also that</p>
<div class="example"><p><code>
ProxyBlock *
</code></p></div>
<p>blocks connections to all sites.</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="ProxyDomain" id="ProxyDomain">ProxyDomain</a> <a name="proxydomain" id="proxydomain">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Default domain name for proxied requests</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyDomain <var>Domain</var></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
</table>
<p>This directive is only useful for Apache proxy servers within
intranets. The <code class="directive">ProxyDomain</code> directive specifies
the default domain which the apache proxy server will belong to. If a
request to a host without a domain name is encountered, a redirection
response to the same host with the configured <var>Domain</var> appended
will be generated.</p>
<div class="example"><h3>Example</h3><p><code>
ProxyRemote * http://firewall.mycompany.com:81<br />
NoProxy .mycompany.com 192.168.112.0/21<br />
ProxyDomain .mycompany.com
</code></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="ProxyErrorOverride" id="ProxyErrorOverride">ProxyErrorOverride</a> <a name="proxyerroroverride" id="proxyerroroverride">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Override error pages for proxied content</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyErrorOverride On|Off</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyErrorOverride Off</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in version 2.0 and later</td></tr>
</table>
<p>This directive is useful for reverse-proxy setups, where you want to
have a common look and feel on the error pages seen by the end user.
This also allows for included files (via mod_include's SSI) to get
the error code and act accordingly (default behavior would display
the error page of the proxied server, turning this on shows the SSI
Error message).</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="ProxyFtpDirCharset" id="ProxyFtpDirCharset">ProxyFtpDirCharset</a> <a name="proxyftpdircharset" id="proxyftpdircharset">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Define the character set for proxied FTP listings</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyFtpDirCharset <var>character set</var></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyFtpDirCharset ISO-8859-1</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.62 and later</td></tr>
</table>
<p>The <code class="directive">ProxyFtpDirCharset</code> directive defines the
character set to be set for FTP directory listings in HTML generated by
<code class="module"><a href="../mod/mod_proxy_ftp.html">mod_proxy_ftp</a></code>.</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="ProxyIOBufferSize" id="ProxyIOBufferSize">ProxyIOBufferSize</a> <a name="proxyiobuffersize" id="proxyiobuffersize">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determine size of internal data throughput buffer</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyIOBufferSize <var>bytes</var></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyIOBufferSize 8192</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
</table>
<p>The <code class="directive">ProxyIOBufferSize</code> directive adjusts the size
of the internal buffer, which is used as a scratchpad for the data between
input and output. The size must be less or equal <code>8192</code>.</p>
<p>In almost every case there's no reason to change that value.</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="ProxyMatch" id="ProxyMatch"><ProxyMatch></a> <a name="proxymatch" id="proxymatch">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Container for directives applied to regular-expression-matched
proxied resources</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><ProxyMatch <var>regex</var>> ...</ProxyMatch></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
</table>
<p>The <code class="directive"><ProxyMatch></code> directive is
identical to the <code class="directive"><a href="#proxy"><Proxy></a></code> directive, except it matches URLs
using regular expressions.</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="ProxyMaxForwards" id="ProxyMaxForwards">ProxyMaxForwards</a> <a name="proxymaxforwards" id="proxymaxforwards">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximium number of proxies that a request can be forwarded
through</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyMaxForwards <var>number</var></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyMaxForwards 10</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0 and later</td></tr>
</table>
<p>The <code class="directive">ProxyMaxForwards</code> directive specifies the
maximum number of proxies through which a request may pass, if there's no
<code>Max-Forwards</code> header supplied with the request. This is
set to prevent infinite proxy loops, or a DoS attack.</p>
<div class="example"><h3>Example</h3><p><code>
ProxyMaxForwards 15
</code></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="ProxyPass" id="ProxyPass">ProxyPass</a> <a name="proxypass" id="proxypass">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maps remote servers into the local server URL-space</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPass [<var>path</var>] !|<var>url</var></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
</table>
<p>This directive allows remote servers to be mapped into the space of
the local server; the local server does not act as a proxy in the
conventional sense, but appears to be a mirror of the remote
server. <var>path</var> is the name of a local virtual path; <var>url</var>
is a partial URL for the remote server and cannot include a query
string.</p>
<p>Suppose the local server has address <code>http://example.com/</code>;
then</p>
<div class="example"><p><code>
ProxyPass /mirror/foo/ http://backend.example.com/
</code></p></div>
<p>will cause a local request for
<code>http://example.com/mirror/foo/bar</code> to be internally converted
into a proxy request to <code>http://backend.example.com/bar</code>.</p>
<p>The <code>!</code> directive is useful in situations where you don't want
to reverse-proxy a subdirectory, <em>e.g.</em></p>
<div class="example"><p><code>
ProxyPass /mirror/foo/i !<br />
ProxyPass /mirror/foo http://backend.example.com
</code></p></div>
<p>will proxy all requests to <code>/mirror/foo</code> to
<code>backend.example.com</code> <em>except</em> requests made to
<code>/mirror/foo/i</code>.</p>
<div class="note"><h3>Note</h3>
<p>Order is important. you need to put the exclusions <em>before</em> the
general proxypass directive.</p>
</div>
<p>When used inside a <code class="directive"><a href="../mod/core.html#location"><Location></a></code> section, the first argument is omitted and the local
directory is obtained from the <code class="directive"><a href="../mod/core.html#location"><Location></a></code>.</p>
<div class="warning">The <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive should
usually be set <strong>off</strong> when using
<code class="directive">ProxyPass</code>.</div>
<p>If you require a more flexible reverse-proxy configuration, see the
<code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> directive with the
<code>[P]</code> flag.</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="ProxyPassReverse" id="ProxyPassReverse">ProxyPassReverse</a> <a name="proxypassreverse" id="proxypassreverse">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Adjusts the URL in HTTP response headers sent from a reverse
proxied server</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPassReverse [<var>path</var>] <var>url</var></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
</table>
<p>This directive lets Apache adjust the URL in the <code>Location</code>,
<code>Content-Location</code> and <code>URI</code> headers on HTTP redirect
responses. This is essential when Apache is used as a reverse proxy to avoid
by-passing the reverse proxy because of HTTP redirects on the backend
servers which stay behind the reverse proxy.</p>
<p>Only the HTTP response headers specifically mentioned above
will be rewritten. Apache will not rewrite other response
headers, nor will it rewrite URL references inside HTML pages.
This means that if the proxied content contains absolute URL
references, they will by-pass the proxy. A third-party module
that will look inside the HTML and rewrite URL references is Nick
Kew's <a href="http://www.webthing.com/software/mod_proxy_html/">mod_proxy_html</a>.</p>
<p><var>path</var> is the name of a local virtual path. <var>url</var> is a
partial URL for the remote server - the same way they are used for the
<code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.</p>
<p>For example, suppose the local server has address
<code>http://example.com/</code>; then</p>
<div class="example"><p><code>
ProxyPass /mirror/foo/ http://backend.example.com/<br />
ProxyPassReverse /mirror/foo/ http://backend.example.com/
</code></p></div>
<p>will not only cause a local request for the
<code>http://example.com/mirror/foo/bar</code> to be internally converted
into a proxy request to <code>http://backend.example.com/bar</code>
(the functionality <code>ProxyPass</code> provides here). It also takes care
of redirects the server <code>backend.example.com</code> sends: when
<code>http://backend.example.com/bar</code> is redirected by him to
<code>http://backend.example.com/quux</code> Apache adjusts this to
<code>http://example.com/mirror/foo/quux</code> before forwarding the HTTP
redirect response to the client. Note that the hostname used for
constructing the URL is chosen in respect to the setting of the <code class="directive"><a href="../mod/core.html#usecanonicalname">UseCanonicalName</a></code> directive.</p>
<p>Note that this <code class="directive">ProxyPassReverse</code> directive can
also be used in conjunction with the proxy pass-through feature
(<code>RewriteRule ... [P]</code>) from <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>
because its doesn't depend on a corresponding <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.</p>
<p>When used inside a <code class="directive"><a href="../mod/core.html#location"><Location></a></code> section, the first argument is omitted and the local
directory is obtained from the <code class="directive"><a href="../mod/core.html#location"><Location></a></code>.</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="ProxyPreserveHost" id="ProxyPreserveHost">ProxyPreserveHost</a> <a name="proxypreservehost" id="proxypreservehost">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Use incoming Host HTTP request header for proxy
request</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPreserveHost On|Off</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyPreserveHost Off</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.31 and later.</td></tr>
</table>
<p>When enabled, this option will pass the Host: line from the incoming
request to the proxied host, instead of the hostname specified in the
proxypass line.</p>
<p>This option should normally be turned <code>Off</code>. It is mostly
useful in special configurations like proxied mass name-based virtual
hosting, where the original Host header needs to be evaluated by the
backend server.</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="ProxyReceiveBufferSize" id="ProxyReceiveBufferSize">ProxyReceiveBufferSize</a> <a name="proxyreceivebuffersize" id="proxyreceivebuffersize">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Network buffer size for proxied HTTP and FTP
connections</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyReceiveBufferSize <var>bytes</var></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyReceiveBufferSize 0</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
</table>
<p>The <code class="directive">ProxyReceiveBufferSize</code> directive specifies an
explicit (TCP/IP) network buffer size for proxied HTTP and FTP connections,
for increased throughput. It has to be greater than <code>512</code> or set
to <code>0</code> to indicate that the system's default buffer size should
be used.</p>
<div class="example"><h3>Example</h3><p><code>
ProxyReceiveBufferSize 2048
</code></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="ProxyRemote" id="ProxyRemote">ProxyRemote</a> <a name="proxyremote" id="proxyremote">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Remote proxy used to handle certain requests</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRemote <var>match</var> <var>remote-server</var></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
</table>
<p>This defines remote proxies to this proxy. <var>match</var> is either the
name of a URL-scheme that the remote server supports, or a partial URL
for which the remote server should be used, or <code>*</code> to indicate
the server should be contacted for all requests. <var>remote-server</var> is
a partial URL for the remote server. Syntax:</p>
<div class="example"><p><code>
<dfn>remote-server</dfn> =
<var>scheme</var>://<var>hostname</var>[:<var>port</var>]
</code></p></div>
<p><var>scheme</var> is effectively the protocol that should be used to
communicate with the remote server; only <code>http</code> is supported by
this module.</p>
<div class="example"><h3>Example</h3><p><code>
ProxyRemote http://goodguys.com/ http://mirrorguys.com:8000<br />
ProxyRemote * http://cleversite.com<br />
ProxyRemote ftp http://ftpproxy.mydomain.com:8080
</code></p></div>
<p>In the last example, the proxy will forward FTP requests, encapsulated
as yet another HTTP proxy request, to another proxy which can handle
them.</p>
<p>This option also supports reverse proxy configuration - a backend
webserver can be embedded within a virtualhost URL space even if that
server is hidden by another forward proxy.</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="ProxyRemoteMatch" id="ProxyRemoteMatch">ProxyRemoteMatch</a> <a name="proxyremotematch" id="proxyremotematch">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Remote proxy used to handle requests matched by regular
expressions</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRemoteMatch <var>regex</var> <var>remote-server</var></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
</table>
<p>The <code class="directive">ProxyRemoteMatch</code> is identical to the
<code class="directive"><a href="#proxyremote">ProxyRemote</a></code> directive, except the
first argument is a regular expression match against the requested URL.</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="ProxyRequests" id="ProxyRequests">ProxyRequests</a> <a name="proxyrequests" id="proxyrequests">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables forward (standard) proxy requests</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRequests On|Off</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyRequests Off</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
</table>
<p>This allows or prevents Apache from functioning as a forward proxy
server. (Setting ProxyRequests to <code>Off</code> does not disable use of
the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.)</p>
<p>In a typical reverse proxy configuration, this option should be set to
<code>Off</code>.</p>
<p>In order to get the functionality of proxying HTTP or FTP sites, you
need also <code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code> or <code class="module"><a href="../mod/mod_proxy_ftp.html">mod_proxy_ftp</a></code>
(or both) present in the server.</p>
<div class="warning"><h3>Warning</h3>
<p>Do not enable proxying with <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> until you have <a href="#access">secured your server</a>. Open proxy servers are dangerous
both to your network and to the Internet at large.</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="ProxyTimeout" id="ProxyTimeout">ProxyTimeout</a> <a name="proxytimeout" id="proxytimeout">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Network timeout for proxied requests</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyTimeout <var>seconds</var></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyTimeout 300</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.31 and later</td></tr>
</table>
<p>This directive allows a user to specifiy a timeout on proxy requests.
This is useful when you have a slow/buggy appserver which hangs, and you
would rather just return a timeout and fail gracefully instead of waiting
however long it takes the server to return.</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="ProxyVia" id="ProxyVia">ProxyVia</a> <a name="proxyvia" id="proxyvia">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Information provided in the <code>Via</code> HTTP response
header for proxied requests</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyVia On|Off|Full|Block</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyVia Off</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
</table>
<p>This directive controls the use of the <code>Via:</code> HTTP
header by the proxy. Its intended use is to control the flow of of
proxy requests along a chain of proxy servers. See <a href="http://www.ietf.org/rfc/rfc2616.txt">RFC 2616</a> (HTTP/1.1), section
14.45 for an explanation of <code>Via:</code> header lines.</p>
<ul>
<li>If set to <code>Off</code>, which is the default, no special processing
is performed. If a request or reply contains a <code>Via:</code> header,
it is passed through unchanged.</li>
<li>If set to <code>On</code>, each request and reply will get a
<code>Via:</code> header line added for the current host.</li>
<li>If set to <code>Full</code>, each generated <code>Via:</code> header
line will additionally have the Apache server version shown as a
<code>Via:</code> comment field.</li>
<li>If set to <code>Block</code>, every proxy request will have all its
<code>Via:</code> header lines removed. No new <code>Via:</code> header will
be generated.</li>
</ul>
</div>
</div>
<div class="bottomlang">
<p><span>Available Languages: </span><a href="../en/mod/mod_proxy.html" title="English"> en </a></p>
</div><div id="footer">
<p class="apache">Copyright 2009 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p>
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