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16 <p class="apache">Apache HTTP Server Version 2.0</p>
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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="#proxyftpdircharset">ProxyFtpDirCharset</a></li>
70 <li><img alt="" src="../images/down.gif" /> <a href="#proxyiobuffersize">ProxyIOBufferSize</a></li>
71 <li><img alt="" src="../images/down.gif" /> <a href="#proxymatch"><ProxyMatch></a></li>
72 <li><img alt="" src="../images/down.gif" /> <a href="#proxymaxforwards">ProxyMaxForwards</a></li>
73 <li><img alt="" src="../images/down.gif" /> <a href="#proxypass">ProxyPass</a></li>
74 <li><img alt="" src="../images/down.gif" /> <a href="#proxypassreverse">ProxyPassReverse</a></li>
75 <li><img alt="" src="../images/down.gif" /> <a href="#proxypreservehost">ProxyPreserveHost</a></li>
76 <li><img alt="" src="../images/down.gif" /> <a href="#proxyreceivebuffersize">ProxyReceiveBufferSize</a></li>
77 <li><img alt="" src="../images/down.gif" /> <a href="#proxyremote">ProxyRemote</a></li>
78 <li><img alt="" src="../images/down.gif" /> <a href="#proxyremotematch">ProxyRemoteMatch</a></li>
79 <li><img alt="" src="../images/down.gif" /> <a href="#proxyrequests">ProxyRequests</a></li>
80 <li><img alt="" src="../images/down.gif" /> <a href="#proxytimeout">ProxyTimeout</a></li>
81 <li><img alt="" src="../images/down.gif" /> <a href="#proxyvia">ProxyVia</a></li>
85 <li><img alt="" src="../images/down.gif" /> <a href="#forwardreverse">Forward and Reverse Proxies</a></li>
86 <li><img alt="" src="../images/down.gif" /> <a href="#examples">Basic Examples</a></li>
87 <li><img alt="" src="../images/down.gif" /> <a href="#access">Controlling access to your proxy</a></li>
88 <li><img alt="" src="../images/down.gif" /> <a href="#ftp-proxy">FTP Proxy</a></li>
89 <li><img alt="" src="../images/down.gif" /> <a href="#startup">Slow Startup</a></li>
90 <li><img alt="" src="../images/down.gif" /> <a href="#intranet">Intranet Proxy</a></li>
91 <li><img alt="" src="../images/down.gif" /> <a href="#envsettings">Protocol Adjustments</a></li>
92 </ul><h3>See also</h3>
94 <li><code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code></li>
95 <li><code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code></li>
96 <li><code class="module"><a href="../mod/mod_proxy_ftp.html">mod_proxy_ftp</a></code></li>
97 <li><code class="module"><a href="../mod/mod_proxy_connect.html">mod_proxy_connect</a></code></li>
98 <li><code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code></li>
100 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
101 <div class="section">
102 <h2><a name="forwardreverse" id="forwardreverse">Forward and Reverse Proxies</a></h2>
103 <p>Apache can be configured in both a <dfn>forward</dfn> and
104 <dfn>reverse</dfn> proxy mode.</p>
106 <p>An ordinary <dfn>forward proxy</dfn> is an intermediate
107 server that sits between the client and the <em>origin
108 server</em>. In order to get content from the origin server,
109 the client sends a request to the proxy naming the origin server
110 as the target and the proxy then requests the content from the
111 origin server and returns it to the client. The client must be
112 specially configured to use the forward proxy to access other
115 <p>A typical usage of a forward proxy is to provide Internet
116 access to internal clients that are otherwise restricted by a
117 firewall. The forward proxy can also use caching (as provided
118 by <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code>) to reduce network usage.</p>
120 <p>The forward proxy is activated using the <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive. Because
121 forward proxys allow clients to access arbitrary sites through
122 your server and to hide their true origin, it is essential that
123 you <a href="#access">secure your server</a> so that only
124 authorized clients can access the proxy before activating a
127 <p>A <dfn>reverse proxy</dfn>, by contrast, appears to the
128 client just like an ordinary web server. No special
129 configuration on the client is necessary. The client makes
130 ordinary requests for content in the name-space of the reverse
131 proxy. The reverse proxy then decides where to send those
132 requests, and returns the content as if it was itself the
135 <p>A typical usage of a reverse proxy is to provide Internet
136 users access to a server that is behind a firewall. Reverse
137 proxies can also be used to balance load among several back-end
138 servers, or to provide caching for a slower back-end server.
139 In addition, reverse proxies can be used simply to bring
140 several servers into the same URL space.</p>
142 <p>A reverse proxy is activated using the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive or the
143 <code>[P]</code> flag to the <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> directive. It is
144 <strong>not</strong> necessary to turn <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> on in order to
145 configure a reverse proxy.</p>
146 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
147 <div class="section">
148 <h2><a name="examples" id="examples">Basic Examples</a></h2>
150 <p>The examples below are only a very basic idea to help you
151 get started. Please read the documentation on the individual
154 <p>In addition, if you wish to have caching enabled, consult
155 the documentation from <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code>.</p>
157 <div class="example"><h3>Forward Proxy</h3><p><code>
158 ProxyRequests On<br />
161 <Proxy *><br />
162 <span class="indent">
163 Order deny,allow<br />
165 Allow from internal.example.com<br />
170 <div class="example"><h3>Reverse Proxy</h3><p><code>
171 ProxyRequests Off<br />
173 <Proxy *><br />
174 <span class="indent">
175 Order deny,allow<br />
180 ProxyPass /foo http://foo.example.com/bar<br />
181 ProxyPassReverse /foo http://foo.example.com/bar
183 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
184 <div class="section">
185 <h2><a name="access" id="access">Controlling access to your proxy</a></h2>
186 <p>You can control who can access your proxy via the <code class="directive"><a href="#proxy"><Proxy></a></code> control block as in
187 the following example:</p>
189 <div class="example"><p><code>
190 <Proxy *><br />
191 <span class="indent">
192 Order Deny,Allow<br />
194 Allow from 192.168.0<br />
199 <p>For more information on access control directives, see
200 <code class="module"><a href="../mod/mod_access.html">mod_access</a></code>.</p>
202 <p>Strictly limiting access is essential if you are using a
203 forward proxy (using the <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive).
204 Otherwise, your server can be used by any client to access
205 arbitrary hosts while hiding his or her true identity. This is
206 dangerous both for your network and for the Internet at large.
207 When using a reverse proxy (using the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive with
208 <code>ProxyRequests Off</code>), access control is less
209 critical because clients can only contact the hosts that you
210 have specifically configured.</p>
212 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
213 <div class="section">
214 <h2><a name="ftp-proxy" id="ftp-proxy">FTP Proxy</a></h2>
217 <h3><a name="mimetypes" id="mimetypes">Why doesn't file type <var>xxx</var>
218 download via FTP?</a></h3>
219 <p>You probably don't have that particular file type defined as
220 <code>application/octet-stream</code> in your proxy's mime.types
221 configuration file. A useful line can be</p>
223 <div class="example"><pre>application/octet-stream bin dms lha lzh exe class tgz taz</pre></div>
226 <h3><a name="type" id="type">How can I force an FTP ASCII download of
227 File <var>xxx</var>?</a></h3>
228 <p>In the rare situation where you must download a specific file using the
229 FTP <code>ASCII</code> transfer method (while the default transfer is in
230 <code>binary</code> mode), you can override <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>'s
231 default by suffixing the request with <code>;type=a</code> to force an
232 ASCII transfer. (FTP Directory listings are always executed in ASCII mode,
236 <h3><a name="percent2fhck" id="percent2fhck">How can I access FTP files outside
237 of my home directory?</a></h3>
238 <p>An FTP URI is interpreted relative to the home directory of the user
239 who is logging in. Alas, to reach higher directory levels you cannot
240 use /../, as the dots are interpreted by the browser and not actually
241 sent to the FTP server. To address this problem, the so called <dfn>Squid
242 %2f hack</dfn> was implemented in the Apache FTP proxy; it is a
243 solution which is also used by other popular proxy servers like the <a href="http://www.squid-cache.org/">Squid Proxy Cache</a>. By
244 prepending <code>/%2f</code> to the path of your request, you can make
245 such a proxy change the FTP starting directory to <code>/</code> (instead
246 of the home directory). For example, to retrieve the file
247 <code>/etc/motd</code>, you would use the URL:</p>
249 <div class="example"><p><code>
250 ftp://<var>user</var>@<var>host</var>/%2f/etc/motd
254 <h3><a name="ftppass" id="ftppass">How can I hide the FTP cleartext password
255 in my browser's URL line?</a></h3>
256 <p>To log in to an FTP server by username and password, Apache uses
257 different strategies. In absense of a user name and password in the URL
258 altogether, Apache sends an anonymous login to the FTP server,
261 <div class="example"><p><code>
262 user: anonymous<br />
263 password: apache_proxy@
266 <p>This works for all popular FTP servers which are configured for
267 anonymous access.</p>
269 <p>For a personal login with a specific username, you can embed the user
270 name into the URL, like in:</p>
272 <div class="example"><p><code>
273 ftp://<var>username</var>@<var>host</var>/myfile
276 <p>If the FTP server asks for a password when given this username (which
277 it should), then Apache will reply with a <code>401</code> (Authorization
278 required) response, which causes the Browser to pop up the
279 username/password dialog. Upon entering the password, the connection
280 attempt is retried, and if successful, the requested resource is
281 presented. The advantage of this procedure is that your browser does not
282 display the password in cleartext (which it would if you had used</p>
284 <div class="example"><p><code>
285 ftp://<var>username</var>:<var>password</var>@<var>host</var>/myfile
288 <p>in the first place).</p>
290 <div class="note"><h3>Note</h3>
291 <p>The password which is transmitted in such a way is not encrypted on
292 its way. It travels between your browser and the Apache proxy server in
293 a base64-encoded cleartext string, and between the Apache proxy and the
294 FTP server as plaintext. You should therefore think twice before
295 accessing your FTP server via HTTP (or before accessing your personal
296 files via FTP at all!) When using unsecure channels, an eavesdropper
297 might intercept your password on its way.</p>
300 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
301 <div class="section">
302 <h2><a name="startup" id="startup">Slow Startup</a></h2>
303 <p>If you're using the <code class="directive"><a href="#proxyblock">ProxyBlock</a></code> directive, hostnames' IP addresses are looked up
304 and cached during startup for later match test. This may take a few
305 seconds (or more) depending on the speed with which the hostname lookups
307 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
308 <div class="section">
309 <h2><a name="intranet" id="intranet">Intranet Proxy</a></h2>
310 <p>An Apache proxy server situated in an intranet needs to forward
311 external requests through the company's firewall (for this, configure
312 the <code class="directive"><a href="#proxyremote">ProxyRemote</a></code> directive
313 to forward the respective <var>scheme</var> to the firewall proxy).
314 However, when it has to
315 access resources within the intranet, it can bypass the firewall when
316 accessing hosts. The <code class="directive"><a href="#noproxy">NoProxy</a></code>
317 directive is useful for specifying which hosts belong to the intranet and
318 should be accessed directly.</p>
320 <p>Users within an intranet tend to omit the local domain name from their
321 WWW requests, thus requesting "http://somehost/" instead of
322 <code>http://somehost.example.com/</code>. Some commercial proxy servers
323 let them get away with this and simply serve the request, implying a
324 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
325 a redirect response and send the client to the correct, fully qualified,
326 server address. This is the preferred method since the user's bookmark
327 files will then contain fully qualified hosts.</p>
328 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
329 <div class="section">
330 <h2><a name="envsettings" id="envsettings">Protocol Adjustments</a></h2>
331 <p>For circumstances where you have a application server which doesn't
332 implement keepalives or HTTP/1.1 properly, there are 2 environment
333 variables which when set send a HTTP/1.0 with no keepalive. These are set
334 via the <code class="directive"><a href="../mod/mod_env.html#setenv">SetEnv</a></code> directive.</p>
336 <p>These are the <code>force-proxy-request-1.0</code> and
337 <code>proxy-nokeepalive</code> notes.</p>
339 <div class="example"><p><code>
340 <Location /buggyappserver/><br />
341 <span class="indent">
342 ProxyPass http://buggyappserver:7001/foo/<br />
343 SetEnv force-proxy-request-1.0 1<br />
344 SetEnv proxy-nokeepalive 1<br />
349 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
350 <div class="directive-section"><h2><a name="AllowCONNECT" id="AllowCONNECT">AllowCONNECT</a> <a name="allowconnect" id="allowconnect">Directive</a></h2>
351 <table class="directive">
352 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Ports that are allowed to <code>CONNECT</code> through the
354 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AllowCONNECT <var>port</var> [<var>port</var>] ...</code></td></tr>
355 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AllowCONNECT 443 563</code></td></tr>
356 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
357 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
358 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
360 <p>The <code class="directive">AllowCONNECT</code> directive specifies a list
361 of port numbers to which the proxy <code>CONNECT</code> method may
362 connect. Today's browsers use this method when a <code>https</code>
363 connection is requested and proxy tunneling over HTTP is in effect.</p>
365 <p>By default, only the default https port (<code>443</code>) and the
366 default snews port (<code>563</code>) are enabled. Use the
367 <code class="directive">AllowCONNECT</code> directive to override this default and
368 allow connections to the listed ports only.</p>
370 <p>Note that you'll need to have <code class="module"><a href="../mod/mod_proxy_connect.html">mod_proxy_connect</a></code> present
371 in the server in order to get the support for the <code>CONNECT</code> at
375 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
376 <div class="directive-section"><h2><a name="NoProxy" id="NoProxy">NoProxy</a> <a name="noproxy" id="noproxy">Directive</a></h2>
377 <table class="directive">
378 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Hosts, domains, or networks that will be connected to
380 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>NoProxy <var>host</var> [<var>host</var>] ...</code></td></tr>
381 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
382 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
383 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
385 <p>This directive is only useful for Apache proxy servers within
386 intranets. The <code class="directive">NoProxy</code> directive specifies a
387 list of subnets, IP addresses, hosts and/or domains, separated by
388 spaces. A request to a host which matches one or more of these is
389 always served directly, without forwarding to the configured
390 <code class="directive"><a href="#proxyremote">ProxyRemote</a></code> proxy server(s).</p>
392 <div class="example"><h3>Example</h3><p><code>
393 ProxyRemote * http://firewall.mycompany.com:81<br />
394 NoProxy .mycompany.com 192.168.112.0/21
397 <p>The <var>host</var> arguments to the <code class="directive">NoProxy</code>
398 directive are one of the following type list:</p>
402 <dt><var><a name="domain" id="domain">Domain</a></var></dt>
404 <p>A <dfn>Domain</dfn> is a partially qualified DNS domain name, preceded
405 by a period. It represents a list of hosts which logically belong to the
406 same DNS domain or zone (<em>i.e.</em>, the suffixes of the hostnames are
407 all ending in <var>Domain</var>).</p>
409 <div class="example"><h3>Examples</h3><p><code>
413 <p>To distinguish <var>Domain</var>s from <var><a href="#hostname">Hostname</a></var>s (both syntactically and semantically; a DNS domain can
414 have a DNS A record, too!), <var>Domain</var>s are always written with a
417 <div class="note"><h3>Note</h3>
418 <p>Domain name comparisons are done without regard to the case, and
419 <var>Domain</var>s are always assumed to be anchored in the root of the
420 DNS tree, therefore two domains <code>.MyDomain.com</code> and
421 <code>.mydomain.com.</code> (note the trailing period) are considered
422 equal. Since a domain comparison does not involve a DNS lookup, it is much
423 more efficient than subnet comparison.</p>
427 <dt><var><a name="subnet" id="subnet">SubNet</a></var></dt>
429 <p>A <dfn>SubNet</dfn> is a partially qualified internet address in
430 numeric (dotted quad) form, optionally followed by a slash and the netmask,
431 specified as the number of significant bits in the <var>SubNet</var>. It is
432 used to represent a subnet of hosts which can be reached over a common
433 network interface. In the absence of the explicit net mask it is assumed
434 that omitted (or zero valued) trailing digits specify the mask. (In this
435 case, the netmask can only be multiples of 8 bits wide.) Examples:</p>
438 <dt><code>192.168</code> or <code>192.168.0.0</code></dt>
439 <dd>the subnet 192.168.0.0 with an implied netmask of 16 valid bits
440 (sometimes used in the netmask form <code>255.255.0.0</code>)</dd>
441 <dt><code>192.168.112.0/21</code></dt>
442 <dd>the subnet <code>192.168.112.0/21</code> with a netmask of 21
443 valid bits (also used in the form 255.255.248.0)</dd>
446 <p>As a degenerate case, a <em>SubNet</em> with 32 valid bits is the
447 equivalent to an <var><a href="#ipadr">IPAddr</a></var>, while a <var>SubNet</var> with zero
448 valid bits (<em>e.g.</em>, 0.0.0.0/0) is the same as the constant
449 <var>_Default_</var>, matching any IP address.</p></dd>
452 <dt><var><a name="ipaddr" id="ipaddr">IPAddr</a></var></dt>
454 <p>A <dfn>IPAddr</dfn> represents a fully qualified internet address in
455 numeric (dotted quad) form. Usually, this address represents a host, but
456 there need not necessarily be a DNS domain name connected with the
458 <div class="example"><h3>Example</h3><p><code>
462 <div class="note"><h3>Note</h3>
463 <p>An <var>IPAddr</var> does not need to be resolved by the DNS system, so
464 it can result in more effective apache performance.</p>
468 <dt><var><a name="hostname" id="hostname">Hostname</a></var></dt>
470 <p>A <dfn>Hostname</dfn> is a fully qualified DNS domain name which can
471 be resolved to one or more <var><a href="#ipaddr">IPAddrs</a></var> via the
472 DNS domain name service. It represents a logical host (in contrast to
473 <var><a href="#domain">Domain</a></var>s, see above) and must be resolvable
474 to at least one <var><a href="#ipaddr">IPAddr</a></var> (or often to a list
475 of hosts with different <var><a href="#ipaddr">IPAddr</a></var>s).</p>
477 <div class="example"><h3>Examples</h3><p><code>
478 prep.ai.mit.edu<br />
482 <div class="note"><h3>Note</h3>
483 <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
484 DNS lookup can be avoided. Name resolution in Apache can take a remarkable
485 deal of time when the connection to the name server uses a slow PPP
487 <p><var>Hostname</var> comparisons are done without regard to the case,
488 and <var>Hostname</var>s are always assumed to be anchored in the root
489 of the DNS tree, therefore two hosts <code>WWW.MyDomain.com</code>
490 and <code>www.mydomain.com.</code> (note the trailing period) are
491 considered equal.</p>
497 <li><a href="../dns-caveats.html">DNS Issues</a></li>
500 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
501 <div class="directive-section"><h2><a name="Proxy" id="Proxy"><Proxy></a> <a name="proxy" id="proxy">Directive</a></h2>
502 <table class="directive">
503 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Container for directives applied to proxied resources</td></tr>
504 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Proxy <var>wildcard-url</var>> ...</Proxy></code></td></tr>
505 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
506 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
507 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
509 <p>Directives placed in <code class="directive"><Proxy></code>
510 sections apply only to matching proxied content. Shell-style wildcards are
513 <p>For example, the following will allow only hosts in
514 <code>yournetwork.example.com</code> to access content via your proxy
517 <div class="example"><p><code>
518 <Proxy *><br />
519 <span class="indent">
520 Order Deny,Allow<br />
522 Allow from yournetwork.example.com<br />
527 <p>The following example will process all files in the <code>foo</code>
528 directory of <code>example.com</code> through the <code>INCLUDES</code>
529 filter when they are sent through the proxy server:</p>
531 <div class="example"><p><code>
532 <Proxy http://example.com/foo/*><br />
533 <span class="indent">
534 SetOutputFilter INCLUDES<br />
540 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
541 <div class="directive-section"><h2><a name="ProxyBadHeader" id="ProxyBadHeader">ProxyBadHeader</a> <a name="proxybadheader" id="proxybadheader">Directive</a></h2>
542 <table class="directive">
543 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determines how to handle bad header lines in a
545 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyBadHeader IsError|Ignore|StartBody</code></td></tr>
546 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyBadHeader IsError</code></td></tr>
547 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
548 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
549 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
550 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.44 and later</td></tr>
552 <p>The <code class="directive">ProxyBadHeader</code> directive determines the
553 behaviour of <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> if it receives syntactically invalid
554 header lines (<em>i.e.</em> containing no colon). The following arguments
558 <dt><code>IsError</code></dt>
559 <dd>Abort the request and end up with a 502 (Bad Gateway) response. This is
560 the default behaviour.</dd>
562 <dt><code>Ignore</code></dt>
563 <dd>Treat bad header lines as if they weren't sent.</dd>
565 <dt><code>StartBody</code></dt>
566 <dd>When receiving the first bad header line, finish reading the headers and
567 treat the remainder as body. This helps to work around buggy backend servers
568 which forget to insert an empty line between the headers and the body.</dd>
572 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
573 <div class="directive-section"><h2><a name="ProxyBlock" id="ProxyBlock">ProxyBlock</a> <a name="proxyblock" id="proxyblock">Directive</a></h2>
574 <table class="directive">
575 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Words, hosts, or domains that are banned from being
577 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyBlock *|<var>word</var>|<var>host</var>|<var>domain</var>
578 [<var>word</var>|<var>host</var>|<var>domain</var>] ...</code></td></tr>
579 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
580 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
581 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
583 <p>The <code class="directive">ProxyBlock</code> directive specifies a list of
584 words, hosts and/or domains, separated by spaces. HTTP, HTTPS, and
585 FTP document requests to sites whose names contain matched words,
586 hosts or domains are <em>blocked</em> by the proxy server. The proxy
587 module will also attempt to determine IP addresses of list items which
588 may be hostnames during startup, and cache them for match test as
589 well. That may slow down the startup time of the server.</p>
591 <div class="example"><h3>Example</h3><p><code>
592 ProxyBlock joes-garage.com some-host.co.uk rocky.wotsamattau.edu
595 <p><code>rocky.wotsamattau.edu</code> would also be matched if referenced by
598 <p>Note that <code>wotsamattau</code> would also be sufficient to match
599 <code>wotsamattau.edu</code>.</p>
601 <p>Note also that</p>
603 <div class="example"><p><code>
607 <p>blocks connections to all sites.</p>
610 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
611 <div class="directive-section"><h2><a name="ProxyDomain" id="ProxyDomain">ProxyDomain</a> <a name="proxydomain" id="proxydomain">Directive</a></h2>
612 <table class="directive">
613 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Default domain name for proxied requests</td></tr>
614 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyDomain <var>Domain</var></code></td></tr>
615 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
616 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
617 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
619 <p>This directive is only useful for Apache proxy servers within
620 intranets. The <code class="directive">ProxyDomain</code> directive specifies
621 the default domain which the apache proxy server will belong to. If a
622 request to a host without a domain name is encountered, a redirection
623 response to the same host with the configured <var>Domain</var> appended
624 will be generated.</p>
626 <div class="example"><h3>Example</h3><p><code>
627 ProxyRemote * http://firewall.mycompany.com:81<br />
628 NoProxy .mycompany.com 192.168.112.0/21<br />
629 ProxyDomain .mycompany.com
633 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
634 <div class="directive-section"><h2><a name="ProxyErrorOverride" id="ProxyErrorOverride">ProxyErrorOverride</a> <a name="proxyerroroverride" id="proxyerroroverride">Directive</a></h2>
635 <table class="directive">
636 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Override error pages for proxied content</td></tr>
637 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyErrorOverride On|Off</code></td></tr>
638 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyErrorOverride Off</code></td></tr>
639 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
640 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
641 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
642 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in version 2.0 and later</td></tr>
644 <p>This directive is useful for reverse-proxy setups, where you want to
645 have a common look and feel on the error pages seen by the end user.
646 This also allows for included files (via mod_include's SSI) to get
647 the error code and act accordingly (default behavior would display
648 the error page of the proxied server, turning this on shows the SSI
652 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
653 <div class="directive-section"><h2><a name="ProxyFtpDirCharset" id="ProxyFtpDirCharset">ProxyFtpDirCharset</a> <a name="proxyftpdircharset" id="proxyftpdircharset">Directive</a></h2>
654 <table class="directive">
655 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Define the character set for proxied FTP listings</td></tr>
656 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyFtpDirCharset <var>character set</var></code></td></tr>
657 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyFtpDirCharset ISO-8859-1</code></td></tr>
658 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
659 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
660 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
661 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.62 and later</td></tr>
663 <p>The <code class="directive">ProxyFtpDirCharset</code> directive defines the
664 character set to be set for FTP directory listings in HTML generated by
665 <code class="module"><a href="../mod/mod_proxy_ftp.html">mod_proxy_ftp</a></code>.</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="ProxyIOBufferSize" id="ProxyIOBufferSize">ProxyIOBufferSize</a> <a name="proxyiobuffersize" id="proxyiobuffersize">Directive</a></h2>
670 <table class="directive">
671 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determine size of internal data throughput buffer</td></tr>
672 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyIOBufferSize <var>bytes</var></code></td></tr>
673 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyIOBufferSize 8192</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">ProxyIOBufferSize</code> directive adjusts the size
679 of the internal buffer, which is used as a scratchpad for the data between
680 input and output. The size must be less or equal <code>8192</code>.</p>
682 <p>In almost every case there's no reason to change that value.</p>
685 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
686 <div class="directive-section"><h2><a name="ProxyMatch" id="ProxyMatch"><ProxyMatch></a> <a name="proxymatch" id="proxymatch">Directive</a></h2>
687 <table class="directive">
688 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Container for directives applied to regular-expression-matched
689 proxied resources</td></tr>
690 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><ProxyMatch <var>regex</var>> ...</ProxyMatch></code></td></tr>
691 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
692 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
693 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
695 <p>The <code class="directive"><ProxyMatch></code> directive is
696 identical to the <code class="directive"><a href="#proxy"><Proxy></a></code> directive, except it matches URLs
697 using regular expressions.</p>
700 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
701 <div class="directive-section"><h2><a name="ProxyMaxForwards" id="ProxyMaxForwards">ProxyMaxForwards</a> <a name="proxymaxforwards" id="proxymaxforwards">Directive</a></h2>
702 <table class="directive">
703 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximium number of proxies that a request can be forwarded
705 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyMaxForwards <var>number</var></code></td></tr>
706 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyMaxForwards 10</code></td></tr>
707 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
708 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
709 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
710 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0 and later</td></tr>
712 <p>The <code class="directive">ProxyMaxForwards</code> directive specifies the
713 maximum number of proxies through which a request may pass, if there's no
714 <code>Max-Forwards</code> header supplied with the request. This is
715 set to prevent infinite proxy loops, or a DoS attack.</p>
717 <div class="example"><h3>Example</h3><p><code>
722 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
723 <div class="directive-section"><h2><a name="ProxyPass" id="ProxyPass">ProxyPass</a> <a name="proxypass" id="proxypass">Directive</a></h2>
724 <table class="directive">
725 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maps remote servers into the local server URL-space</td></tr>
726 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPass [<var>path</var>] !|<var>url</var></code></td></tr>
727 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
728 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
729 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
731 <p>This directive allows remote servers to be mapped into the space of
732 the local server; the local server does not act as a proxy in the
733 conventional sense, but appears to be a mirror of the remote
734 server. <var>path</var> is the name of a local virtual path; <var>url</var>
735 is a partial URL for the remote server and cannot include a query
738 <p>Suppose the local server has address <code>http://example.com/</code>;
741 <div class="example"><p><code>
742 ProxyPass /mirror/foo/ http://backend.example.com/
745 <p>will cause a local request for
746 <code>http://example.com/mirror/foo/bar</code> to be internally converted
747 into a proxy request to <code>http://backend.example.com/bar</code>.</p>
749 <p>The <code>!</code> directive is useful in situations where you don't want
750 to reverse-proxy a subdirectory, <em>e.g.</em></p>
752 <div class="example"><p><code>
753 ProxyPass /mirror/foo/i !<br />
754 ProxyPass /mirror/foo http://backend.example.com
757 <p>will proxy all requests to <code>/mirror/foo</code> to
758 <code>backend.example.com</code> <em>except</em> requests made to
759 <code>/mirror/foo/i</code>.</p>
761 <div class="note"><h3>Note</h3>
762 <p>Order is important. you need to put the exclusions <em>before</em> the
763 general proxypass directive.</p>
766 <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
767 directory is obtained from the <code class="directive"><a href="../mod/core.html#location"><Location></a></code>.</p>
769 <div class="warning">The <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive should
770 usually be set <strong>off</strong> when using
771 <code class="directive">ProxyPass</code>.</div>
773 <p>If you require a more flexible reverse-proxy configuration, see the
774 <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> directive with the
775 <code>[P]</code> flag.</p>
778 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
779 <div class="directive-section"><h2><a name="ProxyPassReverse" id="ProxyPassReverse">ProxyPassReverse</a> <a name="proxypassreverse" id="proxypassreverse">Directive</a></h2>
780 <table class="directive">
781 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Adjusts the URL in HTTP response headers sent from a reverse
782 proxied server</td></tr>
783 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPassReverse [<var>path</var>] <var>url</var></code></td></tr>
784 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
785 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
786 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
788 <p>This directive lets Apache adjust the URL in the <code>Location</code>,
789 <code>Content-Location</code> and <code>URI</code> headers on HTTP redirect
790 responses. This is essential when Apache is used as a reverse proxy to avoid
791 by-passing the reverse proxy because of HTTP redirects on the backend
792 servers which stay behind the reverse proxy.</p>
794 <p>Only the HTTP response headers specifically mentioned above
795 will be rewritten. Apache will not rewrite other response
796 headers, nor will it rewrite URL references inside HTML pages.
797 This means that if the proxied content contains absolute URL
798 references, they will by-pass the proxy. A third-party module
799 that will look inside the HTML and rewrite URL references is Nick
800 Kew's <a href="http://www.webthing.com/software/mod_proxy_html/">mod_proxy_html</a>.</p>
802 <p><var>path</var> is the name of a local virtual path. <var>url</var> is a
803 partial URL for the remote server - the same way they are used for the
804 <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.</p>
806 <p>For example, suppose the local server has address
807 <code>http://example.com/</code>; then</p>
809 <div class="example"><p><code>
810 ProxyPass /mirror/foo/ http://backend.example.com/<br />
811 ProxyPassReverse /mirror/foo/ http://backend.example.com/
814 <p>will not only cause a local request for the
815 <code>http://example.com/mirror/foo/bar</code> to be internally converted
816 into a proxy request to <code>http://backend.example.com/bar</code>
817 (the functionality <code>ProxyPass</code> provides here). It also takes care
818 of redirects the server <code>backend.example.com</code> sends: when
819 <code>http://backend.example.com/bar</code> is redirected by him to
820 <code>http://backend.example.com/quux</code> Apache adjusts this to
821 <code>http://example.com/mirror/foo/quux</code> before forwarding the HTTP
822 redirect response to the client. Note that the hostname used for
823 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>
825 <p>Note that this <code class="directive">ProxyPassReverse</code> directive can
826 also be used in conjunction with the proxy pass-through feature
827 (<code>RewriteRule ... [P]</code>) from <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>
828 because its doesn't depend on a corresponding <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.</p>
830 <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
831 directory is obtained from the <code class="directive"><a href="../mod/core.html#location"><Location></a></code>.</p>
834 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
835 <div class="directive-section"><h2><a name="ProxyPreserveHost" id="ProxyPreserveHost">ProxyPreserveHost</a> <a name="proxypreservehost" id="proxypreservehost">Directive</a></h2>
836 <table class="directive">
837 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Use incoming Host HTTP request header for proxy
839 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPreserveHost On|Off</code></td></tr>
840 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyPreserveHost Off</code></td></tr>
841 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
842 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
843 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
844 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.31 and later.</td></tr>
846 <p>When enabled, this option will pass the Host: line from the incoming
847 request to the proxied host, instead of the hostname specified in the
850 <p>This option should normally be turned <code>Off</code>. It is mostly
851 useful in special configurations like proxied mass name-based virtual
852 hosting, where the original Host header needs to be evaluated by the
856 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
857 <div class="directive-section"><h2><a name="ProxyReceiveBufferSize" id="ProxyReceiveBufferSize">ProxyReceiveBufferSize</a> <a name="proxyreceivebuffersize" id="proxyreceivebuffersize">Directive</a></h2>
858 <table class="directive">
859 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Network buffer size for proxied HTTP and FTP
860 connections</td></tr>
861 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyReceiveBufferSize <var>bytes</var></code></td></tr>
862 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyReceiveBufferSize 0</code></td></tr>
863 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
864 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
865 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
867 <p>The <code class="directive">ProxyReceiveBufferSize</code> directive specifies an
868 explicit (TCP/IP) network buffer size for proxied HTTP and FTP connections,
869 for increased throughput. It has to be greater than <code>512</code> or set
870 to <code>0</code> to indicate that the system's default buffer size should
873 <div class="example"><h3>Example</h3><p><code>
874 ProxyReceiveBufferSize 2048
878 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
879 <div class="directive-section"><h2><a name="ProxyRemote" id="ProxyRemote">ProxyRemote</a> <a name="proxyremote" id="proxyremote">Directive</a></h2>
880 <table class="directive">
881 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Remote proxy used to handle certain requests</td></tr>
882 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRemote <var>match</var> <var>remote-server</var></code></td></tr>
883 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
884 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
885 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
887 <p>This defines remote proxies to this proxy. <var>match</var> is either the
888 name of a URL-scheme that the remote server supports, or a partial URL
889 for which the remote server should be used, or <code>*</code> to indicate
890 the server should be contacted for all requests. <var>remote-server</var> is
891 a partial URL for the remote server. Syntax:</p>
893 <div class="example"><p><code>
894 <dfn>remote-server</dfn> =
895 <var>scheme</var>://<var>hostname</var>[:<var>port</var>]
898 <p><var>scheme</var> is effectively the protocol that should be used to
899 communicate with the remote server; only <code>http</code> is supported by
902 <div class="example"><h3>Example</h3><p><code>
903 ProxyRemote http://goodguys.com/ http://mirrorguys.com:8000<br />
904 ProxyRemote * http://cleversite.com<br />
905 ProxyRemote ftp http://ftpproxy.mydomain.com:8080
908 <p>In the last example, the proxy will forward FTP requests, encapsulated
909 as yet another HTTP proxy request, to another proxy which can handle
912 <p>This option also supports reverse proxy configuration - a backend
913 webserver can be embedded within a virtualhost URL space even if that
914 server is hidden by another forward proxy.</p>
917 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
918 <div class="directive-section"><h2><a name="ProxyRemoteMatch" id="ProxyRemoteMatch">ProxyRemoteMatch</a> <a name="proxyremotematch" id="proxyremotematch">Directive</a></h2>
919 <table class="directive">
920 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Remote proxy used to handle requests matched by regular
921 expressions</td></tr>
922 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRemoteMatch <var>regex</var> <var>remote-server</var></code></td></tr>
923 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
924 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
925 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
927 <p>The <code class="directive">ProxyRemoteMatch</code> is identical to the
928 <code class="directive"><a href="#proxyremote">ProxyRemote</a></code> directive, except the
929 first argument is a regular expression match against the requested URL.</p>
932 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
933 <div class="directive-section"><h2><a name="ProxyRequests" id="ProxyRequests">ProxyRequests</a> <a name="proxyrequests" id="proxyrequests">Directive</a></h2>
934 <table class="directive">
935 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables forward (standard) proxy requests</td></tr>
936 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRequests On|Off</code></td></tr>
937 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyRequests Off</code></td></tr>
938 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
939 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
940 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
942 <p>This allows or prevents Apache from functioning as a forward proxy
943 server. (Setting ProxyRequests to <code>Off</code> does not disable use of
944 the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.)</p>
946 <p>In a typical reverse proxy configuration, this option should be set to
947 <code>Off</code>.</p>
949 <p>In order to get the functionality of proxying HTTP or FTP sites, you
950 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>
951 (or both) present in the server.</p>
953 <div class="warning"><h3>Warning</h3>
954 <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
955 both to your network and to the Internet at large.</p>
959 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
960 <div class="directive-section"><h2><a name="ProxyTimeout" id="ProxyTimeout">ProxyTimeout</a> <a name="proxytimeout" id="proxytimeout">Directive</a></h2>
961 <table class="directive">
962 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Network timeout for proxied requests</td></tr>
963 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyTimeout <var>seconds</var></code></td></tr>
964 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyTimeout 300</code></td></tr>
965 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
966 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
967 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
968 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.31 and later</td></tr>
970 <p>This directive allows a user to specifiy a timeout on proxy requests.
971 This is useful when you have a slow/buggy appserver which hangs, and you
972 would rather just return a timeout and fail gracefully instead of waiting
973 however long it takes the server to return.</p>
976 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
977 <div class="directive-section"><h2><a name="ProxyVia" id="ProxyVia">ProxyVia</a> <a name="proxyvia" id="proxyvia">Directive</a></h2>
978 <table class="directive">
979 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Information provided in the <code>Via</code> HTTP response
980 header for proxied requests</td></tr>
981 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyVia On|Off|Full|Block</code></td></tr>
982 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyVia Off</code></td></tr>
983 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
984 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
985 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
987 <p>This directive controls the use of the <code>Via:</code> HTTP
988 header by the proxy. Its intended use is to control the flow of of
989 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
990 14.45 for an explanation of <code>Via:</code> header lines.</p>
993 <li>If set to <code>Off</code>, which is the default, no special processing
994 is performed. If a request or reply contains a <code>Via:</code> header,
995 it is passed through unchanged.</li>
997 <li>If set to <code>On</code>, each request and reply will get a
998 <code>Via:</code> header line added for the current host.</li>
1000 <li>If set to <code>Full</code>, each generated <code>Via:</code> header
1001 line will additionally have the Apache server version shown as a
1002 <code>Via:</code> comment field.</li>
1004 <li>If set to <code>Block</code>, every proxy request will have all its
1005 <code>Via:</code> header lines removed. No new <code>Via:</code> header will
1011 <div class="bottomlang">
1012 <p><span>Available Languages: </span><a href="../en/mod/mod_proxy.html" title="English"> en </a></p>
1013 </div><div id="footer">
1014 <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>
1015 <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>