1 <?xml version="1.0" encoding="ISO-8859-1"?>
2 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
3 <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head><!--
4 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
5 This file is generated from xml source: DO NOT EDIT
6 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
8 <title>mod_proxy - Apache HTTP Server</title>
9 <link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" />
10 <link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" />
11 <link href="../style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" />
12 <link href="../images/favicon.ico" rel="shortcut icon" /></head>
14 <div id="page-header">
15 <p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p>
16 <p class="apache">Apache HTTP Server Version 2.1</p>
17 <img alt="" src="../images/feather.gif" /></div>
18 <div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div>
20 <a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs-project/">Documentation</a> > <a href="../">Version 2.1</a> > <a href="./">Modules</a></div>
21 <div id="page-content">
22 <div id="preamble"><h1>Apache Module mod_proxy</h1>
24 <p><span>Available Languages: </span><a href="../en/mod/mod_proxy.html" title="English"> en </a></p>
26 <table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>HTTP/1.1 proxy/gateway server</td></tr>
27 <tr><th><a href="module-dict.html#Status">Status:</a></th><td>Extension</td></tr>
28 <tr><th><a href="module-dict.html#ModuleIdentifier">Module Identifier:</a></th><td>proxy_module</td></tr>
29 <tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>mod_proxy.c</td></tr></table>
32 <div class="warning"><h3>Warning</h3>
33 <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
34 network and to the Internet at large.</p>
37 <p>This module implements a proxy/gateway for Apache. It implements
38 proxying capability for <code>FTP</code>, <code>CONNECT</code> (for SSL),
39 <code>HTTP/0.9</code>, <code>HTTP/1.0</code>, and <code>HTTP/1.1</code>.
40 The module can be configured to connect to other proxy modules for these
41 and other protocols.</p>
43 <p>Apache's proxy features are divided into several modules in
44 addition to <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>:
45 <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>
46 and <code class="module"><a href="../mod/mod_proxy_connect.html">mod_proxy_connect</a></code>. Thus, if you want to use
47 one or more of the particular proxy functions, load
48 <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> <em>and</em> the appropriate module(s)
49 into the server (either statically at compile-time or dynamically
50 via the <code class="directive"><a href="../mod/mod_so.html#loadmodule">LoadModule</a></code>
53 <p>In addition, extended features are provided by other modules.
54 Caching is provided by <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code> and related
55 modules. The ability to contact remote servers using the SSL/TLS
56 protocol is provided by the <code>SSLProxy*</code> directives of
57 <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code>. These additional modules will need
58 to be loaded and configured to take advantage of these features.</p>
60 <div id="quickview"><h3 class="directives">Directives</h3>
62 <li><img alt="" src="../images/down.gif" /> <a href="#allowconnect">AllowCONNECT</a></li>
63 <li><img alt="" src="../images/down.gif" /> <a href="#noproxy">NoProxy</a></li>
64 <li><img alt="" src="../images/down.gif" /> <a href="#proxy"><Proxy></a></li>
65 <li><img alt="" src="../images/down.gif" /> <a href="#proxybadheader">ProxyBadHeader</a></li>
66 <li><img alt="" src="../images/down.gif" /> <a href="#proxyblock">ProxyBlock</a></li>
67 <li><img alt="" src="../images/down.gif" /> <a href="#proxydomain">ProxyDomain</a></li>
68 <li><img alt="" src="../images/down.gif" /> <a href="#proxyerroroverride">ProxyErrorOverride</a></li>
69 <li><img alt="" src="../images/down.gif" /> <a href="#proxyiobuffersize">ProxyIOBufferSize</a></li>
70 <li><img alt="" src="../images/down.gif" /> <a href="#proxymatch"><ProxyMatch></a></li>
71 <li><img alt="" src="../images/down.gif" /> <a href="#proxymaxforwards">ProxyMaxForwards</a></li>
72 <li><img alt="" src="../images/down.gif" /> <a href="#proxypass">ProxyPass</a></li>
73 <li><img alt="" src="../images/down.gif" /> <a href="#proxypassreverse">ProxyPassReverse</a></li>
74 <li><img alt="" src="../images/down.gif" /> <a href="#proxypreservehost">ProxyPreserveHost</a></li>
75 <li><img alt="" src="../images/down.gif" /> <a href="#proxyreceivebuffersize">ProxyReceiveBufferSize</a></li>
76 <li><img alt="" src="../images/down.gif" /> <a href="#proxyremote">ProxyRemote</a></li>
77 <li><img alt="" src="../images/down.gif" /> <a href="#proxyremotematch">ProxyRemoteMatch</a></li>
78 <li><img alt="" src="../images/down.gif" /> <a href="#proxyrequests">ProxyRequests</a></li>
79 <li><img alt="" src="../images/down.gif" /> <a href="#proxytimeout">ProxyTimeout</a></li>
80 <li><img alt="" src="../images/down.gif" /> <a href="#proxyvia">ProxyVia</a></li>
84 <li><img alt="" src="../images/down.gif" /> <a href="#forwardreverse">Forward and Reverse Proxies</a></li>
85 <li><img alt="" src="../images/down.gif" /> <a href="#examples">Basic Examples</a></li>
86 <li><img alt="" src="../images/down.gif" /> <a href="#access">Controlling access to your proxy</a></li>
87 <li><img alt="" src="../images/down.gif" /> <a href="#ftp-proxy">FTP Proxy</a></li>
88 <li><img alt="" src="../images/down.gif" /> <a href="#startup">Slow Startup</a></li>
89 <li><img alt="" src="../images/down.gif" /> <a href="#intranet">Intranet Proxy</a></li>
90 <li><img alt="" src="../images/down.gif" /> <a href="#envsettings">Protocol Adjustments</a></li>
91 </ul><h3>See also</h3>
93 <li><code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code></li>
94 <li><code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code></li>
95 <li><code class="module"><a href="../mod/mod_proxy_ftp.html">mod_proxy_ftp</a></code></li>
96 <li><code class="module"><a href="../mod/mod_proxy_connect.html">mod_proxy_connect</a></code></li>
97 <li><code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code></li>
99 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
100 <div class="section">
101 <h2><a name="forwardreverse" id="forwardreverse">Forward and Reverse Proxies</a></h2>
102 <p>Apache can be configured in both a <dfn>forward</dfn> and
103 <dfn>reverse</dfn> proxy mode.</p>
105 <p>An ordinary <dfn>forward proxy</dfn> is an intermediate
106 server that sits between the client and the <em>origin
107 server</em>. In order to get content from the origin server,
108 the client sends a request to the proxy naming the origin server
109 as the target and the proxy then requests the content from the
110 origin server and returns it to the client. The client must be
111 specially configured to use the forward proxy to access other
114 <p>A typical usage of a forward proxy is to provide Internet
115 access to internal clients that are otherwise restricted by a
116 firewall. The forward proxy can also use caching (as provided
117 by <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code>) to reduce network usage.</p>
119 <p>The forward proxy is activated using the <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive. Because
120 forward proxys allow clients to access arbitrary sites through
121 your server and to hide their true origin, it is essential that
122 you <a href="#access">secure your server</a> so that only
123 authorized clients can access the proxy before activating a
126 <p>A <dfn>reverse proxy</dfn>, by contrast, appears to the
127 client just like an ordinary web server. No special
128 configuration on the client is necessary. The client makes
129 ordinary requests for content in the name-space of the reverse
130 proxy. The reverse proxy then decides where to send those
131 requests, and returns the content as if it was itself the
134 <p>A typical usage of a reverse proxy is to provide Internet
135 users access to a server that is behind a firewall. Reverse
136 proxies can also be used to balance load among several back-end
137 servers, or to provide caching for a slower back-end server.
138 In addition, reverse proxies can be used simply to bring
139 several servers into the same URL space.</p>
141 <p>A reverse proxy is activated using the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive or the
142 <code>[P]</code> flag to the <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> directive. It is
143 <strong>not</strong> necessary to turn <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> on in order to
144 configure a reverse proxy.</p>
145 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
146 <div class="section">
147 <h2><a name="examples" id="examples">Basic Examples</a></h2>
149 <p>The examples below are only a very basic idea to help you
150 get started. Please read the documentation on the individual
153 <p>In addition, if you wish to have caching enabled, consult
154 the documentation from <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code>.</p>
156 <div class="example"><h3>Forward Proxy</h3><p><code>
157 ProxyRequests On<br />
160 <Proxy *><br />
161 <span class="indent">
162 Order deny,allow<br />
164 Allow from internal.example.com<br />
169 <div class="example"><h3>Reverse Proxy</h3><p><code>
170 ProxyRequests Off<br />
172 <Proxy *><br />
173 <span class="indent">
174 Order deny,allow<br />
179 ProxyPass /foo http://foo.example.com/bar<br />
180 ProxyPassReverse /foo http://foo.example.com/bar
182 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
183 <div class="section">
184 <h2><a name="access" id="access">Controlling access to your proxy</a></h2>
185 <p>You can control who can access your proxy via the <code class="directive"><a href="#proxy"><Proxy></a></code> control block as in
186 the following example:</p>
188 <div class="example"><p><code>
189 <Proxy *><br />
190 <span class="indent">
191 Order Deny,Allow<br />
193 Allow from 192.168.0<br />
198 <p>For more information on access control directives, see
199 <code class="module"><a href="../mod/mod_access.html">mod_access</a></code>.</p>
201 <p>Strictly limiting access is essential if you are using a
202 forward proxy (using the <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive).
203 Otherwise, your server can be used by any client to access
204 arbitrary hosts while hiding his or her true identity. This is
205 dangerous both for your network and for the Internet at large.
206 When using a reverse proxy (using the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive with
207 <code>ProxyRequests Off</code>), access control is less
208 critical because clients can only contact the hosts that you
209 have specifically configured.</p>
211 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
212 <div class="section">
213 <h2><a name="ftp-proxy" id="ftp-proxy">FTP Proxy</a></h2>
216 <h3><a name="mimetypes" id="mimetypes">Why doesn't file type <var>xxx</var>
217 download via FTP?</a></h3>
218 <p>You probably don't have that particular file type defined as
219 <code>application/octet-stream</code> in your proxy's mime.types
220 configuration file. A useful line can be</p>
222 <div class="example"><pre>application/octet-stream bin dms lha lzh exe class tgz taz</pre></div>
225 <h3><a name="type" id="type">How can I force an FTP ASCII download of
226 File <var>xxx</var>?</a></h3>
227 <p>In the rare situation where you must download a specific file using the
228 FTP <code>ASCII</code> transfer method (while the default transfer is in
229 <code>binary</code> mode), you can override <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>'s
230 default by suffixing the request with <code>;type=a</code> to force an
231 ASCII transfer. (FTP Directory listings are always executed in ASCII mode,
235 <h3><a name="percent2fhck" id="percent2fhck">How can I access FTP files outside
236 of my home directory?</a></h3>
237 <p>An FTP URI is interpreted relative to the home directory of the user
238 who is logging in. Alas, to reach higher directory levels you cannot
239 use /../, as the dots are interpreted by the browser and not actually
240 sent to the FTP server. To address this problem, the so called <dfn>Squid
241 %2f hack</dfn> was implemented in the Apache FTP proxy; it is a
242 solution which is also used by other popular proxy servers like the <a href="http://www.squid-cache.org/">Squid Proxy Cache</a>. By
243 prepending <code>/%2f</code> to the path of your request, you can make
244 such a proxy change the FTP starting directory to <code>/</code> (instead
245 of the home directory). For example, to retrieve the file
246 <code>/etc/motd</code>, you would use the URL:</p>
248 <div class="example"><p><code>
249 ftp://<var>user</var>@<var>host</var>/%2f/etc/motd
253 <h3><a name="ftppass" id="ftppass">How can I hide the FTP cleartext password
254 in my browser's URL line?</a></h3>
255 <p>To log in to an FTP server by username and password, Apache uses
256 different strategies. In absense of a user name and password in the URL
257 altogether, Apache sends an anonymous login to the FTP server,
260 <div class="example"><p><code>
261 user: anonymous<br />
262 password: apache_proxy@
265 <p>This works for all popular FTP servers which are configured for
266 anonymous access.</p>
268 <p>For a personal login with a specific username, you can embed the user
269 name into the URL, like in:</p>
271 <div class="example"><p><code>
272 ftp://<var>username</var>@<var>host</var>/myfile
275 <p>If the FTP server asks for a password when given this username (which
276 it should), then Apache will reply with a <code>401</code> (Authorization
277 required) response, which causes the Browser to pop up the
278 username/password dialog. Upon entering the password, the connection
279 attempt is retried, and if successful, the requested resource is
280 presented. The advantage of this procedure is that your browser does not
281 display the password in cleartext (which it would if you had used</p>
283 <div class="example"><p><code>
284 ftp://<var>username</var>:<var>password</var>@<var>host</var>/myfile
287 <p>in the first place).</p>
289 <div class="note"><h3>Note</h3>
290 <p>The password which is transmitted in such a way is not encrypted on
291 its way. It travels between your browser and the Apache proxy server in
292 a base64-encoded cleartext string, and between the Apache proxy and the
293 FTP server as plaintext. You should therefore think twice before
294 accessing your FTP server via HTTP (or before accessing your personal
295 files via FTP at all!) When using unsecure channels, an eavesdropper
296 might intercept your password on its way.</p>
299 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
300 <div class="section">
301 <h2><a name="startup" id="startup">Slow Startup</a></h2>
302 <p>If you're using the <code class="directive"><a href="#proxyblock">ProxyBlock</a></code> directive, hostnames' IP addresses are looked up
303 and cached during startup for later match test. This may take a few
304 seconds (or more) depending on the speed with which the hostname lookups
306 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
307 <div class="section">
308 <h2><a name="intranet" id="intranet">Intranet Proxy</a></h2>
309 <p>An Apache proxy server situated in an intranet needs to forward
310 external requests through the company's firewall (for this, configure
311 the <code class="directive"><a href="#proxyremote">ProxyRemote</a></code> directive
312 to forward the respective <var>scheme</var> to the firewall proxy).
313 However, when it has to
314 access resources within the intranet, it can bypass the firewall when
315 accessing hosts. The <code class="directive"><a href="#noproxy">NoProxy</a></code>
316 directive is useful for specifying which hosts belong to the intranet and
317 should be accessed directly.</p>
319 <p>Users within an intranet tend to omit the local domain name from their
320 WWW requests, thus requesting "http://somehost/" instead of
321 <code>http://somehost.example.com/</code>. Some commercial proxy servers
322 let them get away with this and simply serve the request, implying a
323 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
324 a redirect response and send the client to the correct, fully qualified,
325 server address. This is the preferred method since the user's bookmark
326 files will then contain fully qualified hosts.</p>
327 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
328 <div class="section">
329 <h2><a name="envsettings" id="envsettings">Protocol Adjustments</a></h2>
330 <p>For circumstances where you have a application server which doesn't
331 implement keepalives or HTTP/1.1 properly, there are 2 environment
332 variables which when set send a HTTP/1.0 with no keepalive. These are set
333 via the <code class="directive"><a href="../mod/mod_env.html#setenv">SetEnv</a></code> directive.</p>
335 <p>These are the <code>force-proxy-request-1.0</code> and
336 <code>proxy-nokeepalive</code> notes.</p>
338 <div class="example"><p><code>
339 <Location /buggyappserver/><br />
340 <span class="indent">
341 ProxyPass http://buggyappserver:7001/foo/<br />
342 SetEnv force-proxy-request-1.0 1<br />
343 SetEnv proxy-nokeepalive 1<br />
348 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
349 <div class="directive-section"><h2><a name="AllowCONNECT" id="AllowCONNECT">AllowCONNECT</a> <a name="allowconnect" id="allowconnect">Directive</a></h2>
350 <table class="directive">
351 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Ports that are allowed to CONNECT through the
353 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AllowCONNECT <var>port</var> [<var>port</var>] ...</code></td></tr>
354 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AllowCONNECT 443 563</code></td></tr>
355 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
356 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
357 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
359 <p>The <code class="directive">AllowCONNECT</code> directive specifies a list
360 of port numbers to which the proxy <code>CONNECT</code> method may
361 connect. Today's browsers use this method when a <code>https</code>
362 connection is requested and proxy tunneling over HTTP is in effect.</p>
364 <p>By default, only the default https port (<code>443</code>) and the
365 default snews port (<code>563</code>) are enabled. Use the
366 <code class="directive">AllowCONNECT</code> directive to override this default and
367 allow connections to the listed ports only.</p>
369 <p>Note that you'll need to have <code class="module"><a href="../mod/mod_proxy_connect.html">mod_proxy_connect</a></code> present
370 in the server in order to get the support for the <code>CONNECT</code> at
374 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
375 <div class="directive-section"><h2><a name="NoProxy" id="NoProxy">NoProxy</a> <a name="noproxy" id="noproxy">Directive</a></h2>
376 <table class="directive">
377 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Hosts, domains, or networks that will be connected to
379 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>NoProxy <var>host</var> [<var>host</var>] ...</code></td></tr>
380 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
381 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
382 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
384 <p>This directive is only useful for Apache proxy servers within
385 intranets. The <code class="directive">NoProxy</code> directive specifies a
386 list of subnets, IP addresses, hosts and/or domains, separated by
387 spaces. A request to a host which matches one or more of these is
388 always served directly, without forwarding to the configured
389 <code class="directive"><a href="#proxyremote">ProxyRemote</a></code> proxy server(s).</p>
391 <div class="example"><h3>Example</h3><p><code>
392 ProxyRemote * http://firewall.mycompany.com:81<br />
393 NoProxy .mycompany.com 192.168.112.0/21
396 <p>The <var>host</var> arguments to the <code class="directive">NoProxy</code>
397 directive are one of the following type list:</p>
401 <dt><var><a name="domain" id="domain">Domain</a></var></dt>
403 <p>A <dfn>Domain</dfn> is a partially qualified DNS domain name, preceded
404 by a period. It represents a list of hosts which logically belong to the
405 same DNS domain or zone (<em>i.e.</em>, the suffixes of the hostnames are
406 all ending in <var>Domain</var>).</p>
408 <div class="example"><h3>Examples</h3><p><code>
412 <p>To distinguish <var>Domain</var>s from <var><a href="#hostname">Hostname</a></var>s (both syntactically and semantically; a DNS domain can
413 have a DNS A record, too!), <var>Domain</var>s are always written with a
416 <div class="note"><h3>Note</h3>
417 <p>Domain name comparisons are done without regard to the case, and
418 <var>Domain</var>s are always assumed to be anchored in the root of the
419 DNS tree, therefore two domains <code>.MyDomain.com</code> and
420 <code>.mydomain.com.</code> (note the trailing period) are considered
421 equal. Since a domain comparison does not involve a DNS lookup, it is much
422 more efficient than subnet comparison.</p>
426 <dt><var><a name="subnet" id="subnet">SubNet</a></var></dt>
428 <p>A <dfn>SubNet</dfn> is a partially qualified internet address in
429 numeric (dotted quad) form, optionally followed by a slash and the netmask,
430 specified as the number of significant bits in the <var>SubNet</var>. It is
431 used to represent a subnet of hosts which can be reached over a common
432 network interface. In the absence of the explicit net mask it is assumed
433 that omitted (or zero valued) trailing digits specify the mask. (In this
434 case, the netmask can only be multiples of 8 bits wide.) Examples:</p>
437 <dt><code>192.168</code> or <code>192.168.0.0</code></dt>
438 <dd>the subnet 192.168.0.0 with an implied netmask of 16 valid bits
439 (sometimes used in the netmask form <code>255.255.0.0</code>)</dd>
440 <dt><code>192.168.112.0/21</code></dt>
441 <dd>the subnet <code>192.168.112.0/21</code> with a netmask of 21
442 valid bits (also used in the form 255.255.248.0)</dd>
445 <p>As a degenerate case, a <em>SubNet</em> with 32 valid bits is the
446 equivalent to an <var><a href="#ipadr">IPAddr</a></var>, while a <var>SubNet</var> with zero
447 valid bits (<em>e.g.</em>, 0.0.0.0/0) is the same as the constant
448 <var>_Default_</var>, matching any IP address.</p></dd>
451 <dt><var><a name="ipaddr" id="ipaddr">IPAddr</a></var></dt>
453 <p>A <dfn>IPAddr</dfn> represents a fully qualified internet address in
454 numeric (dotted quad) form. Usually, this address represents a host, but
455 there need not necessarily be a DNS domain name connected with the
457 <div class="example"><h3>Example</h3><p><code>
461 <div class="note"><h3>Note</h3>
462 <p>An <var>IPAddr</var> does not need to be resolved by the DNS system, so
463 it can result in more effective apache performance.</p>
467 <dt><var><a name="hostname" id="hostname">Hostname</a></var></dt>
469 <p>A <dfn>Hostname</dfn> is a fully qualified DNS domain name which can
470 be resolved to one or more <var><a href="#ipaddr">IPAddrs</a></var> via the
471 DNS domain name service. It represents a logical host (in contrast to
472 <var><a href="#domain">Domain</a></var>s, see above) and must be resolvable
473 to at least one <var><a href="#ipaddr">IPAddr</a></var> (or often to a list
474 of hosts with different <var><a href="#ipaddr">IPAddr</a></var>s).</p>
476 <div class="example"><h3>Examples</h3><p><code>
477 prep.ai.mit.edu<br />
481 <div class="note"><h3>Note</h3>
482 <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
483 DNS lookup can be avoided. Name resolution in Apache can take a remarkable
484 deal of time when the connection to the name server uses a slow PPP
486 <p><var>Hostname</var> comparisons are done without regard to the case,
487 and <var>Hostname</var>s are always assumed to be anchored in the root
488 of the DNS tree, therefore two hosts <code>WWW.MyDomain.com</code>
489 and <code>www.mydomain.com.</code> (note the trailing period) are
490 considered equal.</p>
496 <li><a href="../dns-caveats.html">DNS Issues</a></li>
499 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
500 <div class="directive-section"><h2><a name="Proxy" id="Proxy"><Proxy></a> <a name="proxy" id="proxy">Directive</a></h2>
501 <table class="directive">
502 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Container for directives applied to proxied resources</td></tr>
503 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Proxy <var>wildcard-url</var>> ...</Proxy></code></td></tr>
504 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
505 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
506 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
508 <p>Directives placed in <code class="directive"><Proxy></code>
509 sections apply only to matching proxied content. Shell-style wildcards are
512 <p>For example, the following will allow only hosts in
513 <code>yournetwork.example.com</code> to access content via your proxy
516 <div class="example"><p><code>
517 <Proxy *><br />
518 <span class="indent">
519 Order Deny,Allow<br />
521 Allow from yournetwork.example.com<br />
526 <p>The following example will process all files in the <code>foo</code>
527 directory of <code>example.com</code> through the <code>INCLUDES</code>
528 filter when they are sent through the proxy server:</p>
530 <div class="example"><p><code>
531 <Proxy http://example.com/foo/*><br />
532 <span class="indent">
533 SetOutputFilter INCLUDES<br />
539 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
540 <div class="directive-section"><h2><a name="ProxyBadHeader" id="ProxyBadHeader">ProxyBadHeader</a> <a name="proxybadheader" id="proxybadheader">Directive</a></h2>
541 <table class="directive">
542 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determines how to handle bad header lines in a
544 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyBadHeader IsError|Ignore|StartBody</code></td></tr>
545 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyBadHeader IsError</code></td></tr>
546 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
547 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
548 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
549 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>available in Apache 2.0.44 and later</td></tr>
551 <p>The <code class="directive">ProxyBadHeader</code> directive determines the
552 behaviour of <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> if it receives syntactically invalid
553 header lines (<em>i.e.</em> containing no colon). The following arguments
557 <dt><code>IsError</code></dt>
558 <dd>Abort the request and end up with a 502 (Bad Gateway) response. This is
559 the default behaviour.</dd>
561 <dt><code>Ignore</code></dt>
562 <dd>Treat bad header lines as if they weren't sent.</dd>
564 <dt><code>StartBody</code></dt>
565 <dd>When receiving the first bad header line, finish reading the headers and
566 treat the remainder as body. This helps to work around buggy backend servers
567 which forget to insert an empty line between the headers and the body.</dd>
571 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
572 <div class="directive-section"><h2><a name="ProxyBlock" id="ProxyBlock">ProxyBlock</a> <a name="proxyblock" id="proxyblock">Directive</a></h2>
573 <table class="directive">
574 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Words, hosts, or domains that are banned from being
576 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyBlock *|<var>word</var>|<var>host</var>|<var>domain</var>
577 [<var>word</var>|<var>host</var>|<var>domain</var>] ...</code></td></tr>
578 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
579 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
580 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
582 <p>The <code class="directive">ProxyBlock</code> directive specifies a list of
583 words, hosts and/or domains, separated by spaces. HTTP, HTTPS, and
584 FTP document requests to sites whose names contain matched words,
585 hosts or domains are <em>blocked</em> by the proxy server. The proxy
586 module will also attempt to determine IP addresses of list items which
587 may be hostnames during startup, and cache them for match test as
588 well. That may slow down the startup time of the server.</p>
590 <div class="example"><h3>Example</h3><p><code>
591 ProxyBlock joes-garage.com some-host.co.uk rocky.wotsamattau.edu
594 <p><code>rocky.wotsamattau.edu</code> would also be matched if referenced by
597 <p>Note that <code>wotsamattau</code> would also be sufficient to match
598 <code>wotsamattau.edu</code>.</p>
600 <p>Note also that</p>
602 <div class="example"><p><code>
606 <p>blocks connections to all sites.</p>
609 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
610 <div class="directive-section"><h2><a name="ProxyDomain" id="ProxyDomain">ProxyDomain</a> <a name="proxydomain" id="proxydomain">Directive</a></h2>
611 <table class="directive">
612 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Default domain name for proxied requests</td></tr>
613 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyDomain <var>Domain</var></code></td></tr>
614 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
615 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
616 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
618 <p>This directive is only useful for Apache proxy servers within
619 intranets. The <code class="directive">ProxyDomain</code> directive specifies
620 the default domain which the apache proxy server will belong to. If a
621 request to a host without a domain name is encountered, a redirection
622 response to the same host with the configured <var>Domain</var> appended
623 will be generated.</p>
625 <div class="example"><h3>Example</h3><p><code>
626 ProxyRemote * http://firewall.mycompany.com:81<br />
627 NoProxy .mycompany.com 192.168.112.0/21<br />
628 ProxyDomain .mycompany.com
632 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
633 <div class="directive-section"><h2><a name="ProxyErrorOverride" id="ProxyErrorOverride">ProxyErrorOverride</a> <a name="proxyerroroverride" id="proxyerroroverride">Directive</a></h2>
634 <table class="directive">
635 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Override error pages for proxied content</td></tr>
636 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyErrorOverride On|Off</code></td></tr>
637 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyErrorOverride Off</code></td></tr>
638 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
639 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
640 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
641 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in version 2.0 and later</td></tr>
643 <p>This directive is useful for reverse-proxy setups, where you want to
644 have a common look and feel on the error pages seen by the end user.
645 This also allows for included files (via mod_include's SSI) to get
646 the error code and act accordingly (default behavior would display
647 the error page of the proxied server, turning this on shows the SSI
651 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
652 <div class="directive-section"><h2><a name="ProxyIOBufferSize" id="ProxyIOBufferSize">ProxyIOBufferSize</a> <a name="proxyiobuffersize" id="proxyiobuffersize">Directive</a></h2>
653 <table class="directive">
654 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determine size of internal data throughput buffer</td></tr>
655 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyIOBufferSize <var>bytes</var></code></td></tr>
656 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyIOBufferSize 8192</code></td></tr>
657 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
658 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
659 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
661 <p>The <code class="directive">ProxyIOBufferSize</code> directive adjusts the size
662 of the internal buffer, which is used as a scratchpad for the data between
663 input and output. The size must be less or equal <code>8192</code>.</p>
665 <p>In almost every case there's no reason to change that value.</p>
668 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
669 <div class="directive-section"><h2><a name="ProxyMatch" id="ProxyMatch"><ProxyMatch></a> <a name="proxymatch" id="proxymatch">Directive</a></h2>
670 <table class="directive">
671 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Container for directives applied to regular-expression-matched
672 proxied resources</td></tr>
673 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><ProxyMatch <var>regex</var>> ...</ProxyMatch></code></td></tr>
674 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
675 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
676 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
678 <p>The <code class="directive"><ProxyMatch></code> directive is
679 identical to the <code class="directive"><a href="#proxy"><Proxy></a></code> directive, except it matches URLs
680 using regular expressions.</p>
683 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
684 <div class="directive-section"><h2><a name="ProxyMaxForwards" id="ProxyMaxForwards">ProxyMaxForwards</a> <a name="proxymaxforwards" id="proxymaxforwards">Directive</a></h2>
685 <table class="directive">
686 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximium number of proxies that a request can be forwarded
688 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyMaxForwards <var>number</var></code></td></tr>
689 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyMaxForwards 10</code></td></tr>
690 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
691 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
692 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
693 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0 and later</td></tr>
695 <p>The <code class="directive">ProxyMaxForwards</code> directive specifies the
696 maximum number of proxies through which a request may pass, if there's no
697 <code>Max-Forwards</code> header supplied with the request. This is
698 set to prevent infinite proxy loops, or a DoS attack.</p>
700 <div class="example"><h3>Example</h3><p><code>
705 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
706 <div class="directive-section"><h2><a name="ProxyPass" id="ProxyPass">ProxyPass</a> <a name="proxypass" id="proxypass">Directive</a></h2>
707 <table class="directive">
708 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maps remote servers into the local server URL-space</td></tr>
709 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPass [<var>path</var>] !|<var>url</var></code></td></tr>
710 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
711 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
712 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
714 <p>This directive allows remote servers to be mapped into the space of
715 the local server; the local server does not act as a proxy in the
716 conventional sense, but appears to be a mirror of the remote
717 server. <var>path</var> is the name of a local virtual path; <var>url</var>
718 is a partial URL for the remote server and cannot include a query
721 <p>Suppose the local server has address <code>http://example.com/</code>;
724 <div class="example"><p><code>
725 ProxyPass /mirror/foo/ http://backend.example.com/
728 <p>will cause a local request for
729 <code>http://example.com/mirror/foo/bar</code> to be internally converted
730 into a proxy request to <code>http://backend.example.com/bar</code>.</p>
732 <p>The <code>!</code> directive is useful in situations where you don't want
733 to reverse-proxy a subdirectory, <em>e.g.</em></p>
735 <div class="example"><p><code>
736 ProxyPass /mirror/foo/i !<br />
737 ProxyPass /mirror/foo http://backend.example.com
740 <p>will proxy all requests to <code>/mirror/foo</code> to
741 <code>backend.example.com</code> <em>except</em> requests made to
742 <code>/mirror/foo/i</code>.</p>
744 <div class="note"><h3>Note</h3>
745 <p>Order is important. you need to put the exclusions <em>before</em> the
746 general proxypass directive.</p>
749 <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
750 directory is obtained from the <code class="directive"><a href="../mod/core.html#location"><Location></a></code>.</p>
752 <div class="warning">The <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive should
753 usually be set <strong>off</strong> when using
754 <code class="directive">ProxyPass</code>.</div>
756 <p>If you require a more flexible reverse-proxy configuration, see the
757 <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> directive with the
758 <code>[P]</code> flag.</p>
761 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
762 <div class="directive-section"><h2><a name="ProxyPassReverse" id="ProxyPassReverse">ProxyPassReverse</a> <a name="proxypassreverse" id="proxypassreverse">Directive</a></h2>
763 <table class="directive">
764 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Adjusts the URL in HTTP response headers sent from a reverse
765 proxied server</td></tr>
766 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPassReverse [<var>path</var>] <var>url</var></code></td></tr>
767 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
768 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
769 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
771 <p>This directive lets Apache adjust the URL in the <code>Location</code>,
772 <code>Content-Location</code> and <code>URI</code> headers on HTTP redirect
773 responses. This is essential when Apache is used as a reverse proxy to avoid
774 by-passing the reverse proxy because of HTTP redirects on the backend
775 servers which stay behind the reverse proxy.</p>
777 <p><var>path</var> is the name of a local virtual path. <var>url</var> is a
778 partial URL for the remote server - the same way they are used for the
779 <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.</p>
781 <p>For example, suppose the local server has address
782 <code>http://example.com/</code>; then</p>
784 <div class="example"><p><code>
785 ProxyPass /mirror/foo/ http://backend.example.com/<br />
786 ProxyPassReverse /mirror/foo/ http://backend.example.com/
789 <p>will not only cause a local request for the
790 <code>http://example.com/mirror/foo/bar</code> to be internally converted
791 into a proxy request to <code>http://backend.example.com/bar</code>
792 (the functionality <code>ProxyPass</code> provides here). It also takes care
793 of redirects the server <code>backend.example.com</code> sends: when
794 <code>http://backend.example.com/bar</code> is redirected by him to
795 <code>http://backend.example.com/quux</code> Apache adjusts this to
796 <code>http://example.com/mirror/foo/quux</code> before forwarding the HTTP
797 redirect response to the client. Note that the hostname used for
798 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>
800 <p>Note that this <code class="directive">ProxyPassReverse</code> directive can
801 also be used in conjunction with the proxy pass-through feature
802 (<code>RewriteRule ... [P]</code>) from <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>
803 because its doesn't depend on a corresponding <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.</p>
805 <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
806 directory is obtained from the <code class="directive"><a href="../mod/core.html#location"><Location></a></code>.</p>
809 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
810 <div class="directive-section"><h2><a name="ProxyPreserveHost" id="ProxyPreserveHost">ProxyPreserveHost</a> <a name="proxypreservehost" id="proxypreservehost">Directive</a></h2>
811 <table class="directive">
812 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Use incoming Host HTTP request header for proxy
814 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPreserveHost On|Off</code></td></tr>
815 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyPreserveHost Off</code></td></tr>
816 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
817 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
818 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
819 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.31 and later.</td></tr>
821 <p>When enabled, this option will pass the Host: line from the incoming
822 request to the proxied host, instead of the hostname specified in the
825 <p>This option should normally be turned <code>Off</code>. It is mostly
826 useful in special configurations like proxied mass name-based virtual
827 hosting, where the original Host header needs to be evaluated by the
831 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
832 <div class="directive-section"><h2><a name="ProxyReceiveBufferSize" id="ProxyReceiveBufferSize">ProxyReceiveBufferSize</a> <a name="proxyreceivebuffersize" id="proxyreceivebuffersize">Directive</a></h2>
833 <table class="directive">
834 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Network buffer size for proxied HTTP and FTP
835 connections</td></tr>
836 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyReceiveBufferSize <var>bytes</var></code></td></tr>
837 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyReceiveBufferSize 0</code></td></tr>
838 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
839 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
840 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
842 <p>The <code class="directive">ProxyReceiveBufferSize</code> directive specifies an
843 explicit (TCP/IP) network buffer size for proxied HTTP and FTP connections,
844 for increased throughput. It has to be greater than <code>512</code> or set
845 to <code>0</code> to indicate that the system's default buffer size should
848 <div class="example"><h3>Example</h3><p><code>
849 ProxyReceiveBufferSize 2048
853 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
854 <div class="directive-section"><h2><a name="ProxyRemote" id="ProxyRemote">ProxyRemote</a> <a name="proxyremote" id="proxyremote">Directive</a></h2>
855 <table class="directive">
856 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Remote proxy used to handle certain requests</td></tr>
857 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRemote <var>match</var> <var>remote-server</var></code></td></tr>
858 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
859 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
860 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
862 <p>This defines remote proxies to this proxy. <var>match</var> is either the
863 name of a URL-scheme that the remote server supports, or a partial URL
864 for which the remote server should be used, or <code>*</code> to indicate
865 the server should be contacted for all requests. <var>remote-server</var> is
866 a partial URL for the remote server. Syntax:</p>
868 <div class="example"><p><code>
869 <dfn>remote-server</dfn> =
870 <var>scheme</var>://<var>hostname</var>[:<var>port</var>]
873 <p><var>scheme</var> is effectively the protocol that should be used to
874 communicate with the remote server; only <code>http</code> is supported by
877 <div class="example"><h3>Example</h3><p><code>
878 ProxyRemote http://goodguys.com/ http://mirrorguys.com:8000<br />
879 ProxyRemote * http://cleversite.com<br />
880 ProxyRemote ftp http://ftpproxy.mydomain.com:8080
883 <p>In the last example, the proxy will forward FTP requests, encapsulated
884 as yet another HTTP proxy request, to another proxy which can handle
887 <p>This option also supports reverse proxy configuration - a backend
888 webserver can be embedded within a virtualhost URL space even if that
889 server is hidden by another forward proxy.</p>
892 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
893 <div class="directive-section"><h2><a name="ProxyRemoteMatch" id="ProxyRemoteMatch">ProxyRemoteMatch</a> <a name="proxyremotematch" id="proxyremotematch">Directive</a></h2>
894 <table class="directive">
895 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Remote proxy used to handle requests matched by regular
896 expressions</td></tr>
897 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRemoteMatch <var>regex</var> <var>remote-server</var></code></td></tr>
898 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
899 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
900 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
902 <p>The <code class="directive">ProxyRemoteMatch</code> is identical to the
903 <code class="directive"><a href="#proxyremote">ProxyRemote</a></code> directive, except the
904 first argument is a regular expression match against the requested URL.</p>
907 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
908 <div class="directive-section"><h2><a name="ProxyRequests" id="ProxyRequests">ProxyRequests</a> <a name="proxyrequests" id="proxyrequests">Directive</a></h2>
909 <table class="directive">
910 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables forward (standard) proxy requests</td></tr>
911 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRequests On|Off</code></td></tr>
912 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyRequests Off</code></td></tr>
913 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
914 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
915 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
917 <p>This allows or prevents Apache from functioning as a forward proxy
918 server. (Setting ProxyRequests to <code>Off</code> does not disable use of
919 the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.)</p>
921 <p>In a typical reverse proxy configuration, this option should be set to
922 <code>Off</code>.</p>
924 <p>In order to get the functionality of proxying HTTP or FTP sites, you
925 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>
926 (or both) present in the server.</p>
928 <div class="warning"><h3>Warning</h3>
929 <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
930 both to your network and to the Internet at large.</p>
934 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
935 <div class="directive-section"><h2><a name="ProxyTimeout" id="ProxyTimeout">ProxyTimeout</a> <a name="proxytimeout" id="proxytimeout">Directive</a></h2>
936 <table class="directive">
937 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Network timeout for proxied requests</td></tr>
938 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyTimeout <var>seconds</var></code></td></tr>
939 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyTimeout 300</code></td></tr>
940 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
941 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
942 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
943 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.31 and later</td></tr>
945 <p>This directive allows a user to specifiy a timeout on proxy requests.
946 This is useful when you have a slow/buggy appserver which hangs, and you
947 would rather just return a timeout and fail gracefully instead of waiting
948 however long it takes the server to return.</p>
951 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
952 <div class="directive-section"><h2><a name="ProxyVia" id="ProxyVia">ProxyVia</a> <a name="proxyvia" id="proxyvia">Directive</a></h2>
953 <table class="directive">
954 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Information provided in the Via HTTP response
955 header for proxied requests</td></tr>
956 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyVia On|Off|Full|Block</code></td></tr>
957 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyVia Off</code></td></tr>
958 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
959 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
960 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
962 <p>This directive controls the use of the <code>Via:</code> HTTP
963 header by the proxy. Its intended use is to control the flow of of
964 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
965 14.45 for an explanation of <code>Via:</code> header lines.</p>
968 <li>If set to <code>Off</code>, which is the default, no special processing
969 is performed. If a request or reply contains a <code>Via:</code> header,
970 it is passed through unchanged.</li>
972 <li>If set to <code>On</code>, each request and reply will get a
973 <code>Via:</code> header line added for the current host.</li>
975 <li>If set to <code>Full</code>, each generated <code>Via:</code> header
976 line will additionally have the Apache server version shown as a
977 <code>Via:</code> comment field.</li>
979 <li>If set to <code>Block</code>, every proxy request will have all its
980 <code>Via:</code> header lines removed. No new <code>Via:</code> header will
986 <div class="bottomlang">
987 <p><span>Available Languages: </span><a href="../en/mod/mod_proxy.html" title="English"> en </a></p>
988 </div><div id="footer">
989 <p class="apache">Maintained by the <a href="http://httpd.apache.org/docs-project/">Apache HTTP Server Documentation Project</a></p>
990 <p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p></div>