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16 <p class="apache">Apache HTTP Server Version 2.1</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>AJP13</code> (Apache JServe Protocol
39 version 1.3), <code>FTP</code>, <code>CONNECT</code> (for SSL),
40 <code>HTTP/0.9</code>, <code>HTTP/1.0</code>, and <code>HTTP/1.1</code>.
41 The module can be configured to connect to other proxy modules for these
42 and other protocols.</p>
44 <p>Apache's proxy features are divided into several modules in
45 addition to <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>:
46 <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>,
47 <code class="module"><a href="../mod/mod_proxy_ajp.html">mod_proxy_ajp</a></code>, <code class="module"><a href="../mod/mod_proxy_balancer.html">mod_proxy_balancer</a></code>,
48 and <code class="module"><a href="../mod/mod_proxy_connect.html">mod_proxy_connect</a></code>. Thus, if you want to use
49 one or more of the particular proxy functions, load
50 <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> <em>and</em> the appropriate module(s)
51 into the server (either statically at compile-time or dynamically
52 via the <code class="directive"><a href="../mod/mod_so.html#loadmodule">LoadModule</a></code>
55 <p>In addition, extended features are provided by other modules.
56 Caching is provided by <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code> and related
57 modules. The ability to contact remote servers using the SSL/TLS
58 protocol is provided by the <code>SSLProxy*</code> directives of
59 <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code>. These additional modules will need
60 to be loaded and configured to take advantage of these features.</p>
62 <div id="quickview"><h3 class="directives">Directives</h3>
64 <li><img alt="" src="../images/down.gif" /> <a href="#allowconnect">AllowCONNECT</a></li>
65 <li><img alt="" src="../images/down.gif" /> <a href="#noproxy">NoProxy</a></li>
66 <li><img alt="" src="../images/down.gif" /> <a href="#proxy"><Proxy></a></li>
67 <li><img alt="" src="../images/down.gif" /> <a href="#proxybadheader">ProxyBadHeader</a></li>
68 <li><img alt="" src="../images/down.gif" /> <a href="#proxyblock">ProxyBlock</a></li>
69 <li><img alt="" src="../images/down.gif" /> <a href="#proxydomain">ProxyDomain</a></li>
70 <li><img alt="" src="../images/down.gif" /> <a href="#proxyerroroverride">ProxyErrorOverride</a></li>
71 <li><img alt="" src="../images/down.gif" /> <a href="#proxyiobuffersize">ProxyIOBufferSize</a></li>
72 <li><img alt="" src="../images/down.gif" /> <a href="#proxymatch"><ProxyMatch></a></li>
73 <li><img alt="" src="../images/down.gif" /> <a href="#proxymaxforwards">ProxyMaxForwards</a></li>
74 <li><img alt="" src="../images/down.gif" /> <a href="#proxypass">ProxyPass</a></li>
75 <li><img alt="" src="../images/down.gif" /> <a href="#proxypassreverse">ProxyPassReverse</a></li>
76 <li><img alt="" src="../images/down.gif" /> <a href="#proxypassreversecookiedomain">ProxyPassReverseCookieDomain</a></li>
77 <li><img alt="" src="../images/down.gif" /> <a href="#proxypassreversecookiepath">ProxyPassReverseCookiePath</a></li>
78 <li><img alt="" src="../images/down.gif" /> <a href="#proxypreservehost">ProxyPreserveHost</a></li>
79 <li><img alt="" src="../images/down.gif" /> <a href="#proxyreceivebuffersize">ProxyReceiveBufferSize</a></li>
80 <li><img alt="" src="../images/down.gif" /> <a href="#proxyremote">ProxyRemote</a></li>
81 <li><img alt="" src="../images/down.gif" /> <a href="#proxyremotematch">ProxyRemoteMatch</a></li>
82 <li><img alt="" src="../images/down.gif" /> <a href="#proxyrequests">ProxyRequests</a></li>
83 <li><img alt="" src="../images/down.gif" /> <a href="#proxytimeout">ProxyTimeout</a></li>
84 <li><img alt="" src="../images/down.gif" /> <a href="#proxyvia">ProxyVia</a></li>
88 <li><img alt="" src="../images/down.gif" /> <a href="#forwardreverse">Forward and Reverse Proxies</a></li>
89 <li><img alt="" src="../images/down.gif" /> <a href="#examples">Basic Examples</a></li>
90 <li><img alt="" src="../images/down.gif" /> <a href="#access">Controlling access to your proxy</a></li>
91 <li><img alt="" src="../images/down.gif" /> <a href="#ftp-proxy">FTP Proxy</a></li>
92 <li><img alt="" src="../images/down.gif" /> <a href="#startup">Slow Startup</a></li>
93 <li><img alt="" src="../images/down.gif" /> <a href="#intranet">Intranet Proxy</a></li>
94 <li><img alt="" src="../images/down.gif" /> <a href="#envsettings">Protocol Adjustments</a></li>
95 </ul><h3>See also</h3>
97 <li><code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code></li>
98 <li><code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code></li>
99 <li><code class="module"><a href="../mod/mod_proxy_ftp.html">mod_proxy_ftp</a></code></li>
100 <li><code class="module"><a href="../mod/mod_proxy_connect.html">mod_proxy_connect</a></code></li>
101 <li><code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code></li>
103 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
104 <div class="section">
105 <h2><a name="forwardreverse" id="forwardreverse">Forward and Reverse Proxies</a></h2>
106 <p>Apache can be configured in both a <dfn>forward</dfn> and
107 <dfn>reverse</dfn> proxy mode.</p>
109 <p>An ordinary <dfn>forward proxy</dfn> is an intermediate
110 server that sits between the client and the <em>origin
111 server</em>. In order to get content from the origin server,
112 the client sends a request to the proxy naming the origin server
113 as the target and the proxy then requests the content from the
114 origin server and returns it to the client. The client must be
115 specially configured to use the forward proxy to access other
118 <p>A typical usage of a forward proxy is to provide Internet
119 access to internal clients that are otherwise restricted by a
120 firewall. The forward proxy can also use caching (as provided
121 by <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code>) to reduce network usage.</p>
123 <p>The forward proxy is activated using the <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive. Because
124 forward proxys allow clients to access arbitrary sites through
125 your server and to hide their true origin, it is essential that
126 you <a href="#access">secure your server</a> so that only
127 authorized clients can access the proxy before activating a
130 <p>A <dfn>reverse proxy</dfn>, by contrast, appears to the
131 client just like an ordinary web server. No special
132 configuration on the client is necessary. The client makes
133 ordinary requests for content in the name-space of the reverse
134 proxy. The reverse proxy then decides where to send those
135 requests, and returns the content as if it was itself the
138 <p>A typical usage of a reverse proxy is to provide Internet
139 users access to a server that is behind a firewall. Reverse
140 proxies can also be used to balance load among several back-end
141 servers, or to provide caching for a slower back-end server.
142 In addition, reverse proxies can be used simply to bring
143 several servers into the same URL space.</p>
145 <p>A reverse proxy is activated using the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive or the
146 <code>[P]</code> flag to the <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> directive. It is
147 <strong>not</strong> necessary to turn <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> on in order to
148 configure a reverse proxy.</p>
149 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
150 <div class="section">
151 <h2><a name="examples" id="examples">Basic Examples</a></h2>
153 <p>The examples below are only a very basic idea to help you
154 get started. Please read the documentation on the individual
157 <p>In addition, if you wish to have caching enabled, consult
158 the documentation from <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code>.</p>
160 <div class="example"><h3>Forward Proxy</h3><p><code>
161 ProxyRequests On<br />
164 <Proxy *><br />
165 <span class="indent">
166 Order deny,allow<br />
168 Allow from internal.example.com<br />
173 <div class="example"><h3>Reverse Proxy</h3><p><code>
174 ProxyRequests Off<br />
176 <Proxy *><br />
177 <span class="indent">
178 Order deny,allow<br />
183 ProxyPass /foo http://foo.example.com/bar<br />
184 ProxyPassReverse /foo http://foo.example.com/bar
186 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
187 <div class="section">
188 <h2><a name="access" id="access">Controlling access to your proxy</a></h2>
189 <p>You can control who can access your proxy via the <code class="directive"><a href="#proxy"><Proxy></a></code> control block as in
190 the following example:</p>
192 <div class="example"><p><code>
193 <Proxy *><br />
194 <span class="indent">
195 Order Deny,Allow<br />
197 Allow from 192.168.0<br />
202 <p>For more information on access control directives, see
203 <code class="module"><a href="../mod/mod_authz_host.html">mod_authz_host</a></code>.</p>
205 <p>Strictly limiting access is essential if you are using a
206 forward proxy (using the <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive).
207 Otherwise, your server can be used by any client to access
208 arbitrary hosts while hiding his or her true identity. This is
209 dangerous both for your network and for the Internet at large.
210 When using a reverse proxy (using the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive with
211 <code>ProxyRequests Off</code>), access control is less
212 critical because clients can only contact the hosts that you
213 have specifically configured.</p>
215 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
216 <div class="section">
217 <h2><a name="ftp-proxy" id="ftp-proxy">FTP Proxy</a></h2>
220 <h3><a name="mimetypes" id="mimetypes">Why doesn't file type <var>xxx</var>
221 download via FTP?</a></h3>
222 <p>You probably don't have that particular file type defined as
223 <code>application/octet-stream</code> in your proxy's mime.types
224 configuration file. A useful line can be</p>
226 <div class="example"><pre>application/octet-stream bin dms lha lzh exe class tgz taz</pre></div>
227 <p>Alternatively you may prefer to default everything to binary:</p>
228 <div class="example"><pre>DefaultType application/octet-stream</pre></div>
231 <h3><a name="type" id="type">How can I force an FTP ASCII download of
232 File <var>xxx</var>?</a></h3>
233 <p>In the rare situation where you must download a specific file using the
234 FTP <code>ASCII</code> transfer method (while the default transfer is in
235 <code>binary</code> mode), you can override <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>'s
236 default by suffixing the request with <code>;type=a</code> to force an
237 ASCII transfer. (FTP Directory listings are always executed in ASCII mode,
241 <h3><a name="ftpnonget" id="ftpnonget">How can I do FTP upload?</a></h3>
242 <p>Currently, only GET is supported for FTP in mod_proxy. You can
243 of course use HTTP upload (POST or PUT) through an Apache proxy.</p>
246 <h3><a name="percent2fhck" id="percent2fhck">How can I access FTP files outside
247 of my home directory?</a></h3>
248 <p>An FTP URI is interpreted relative to the home directory of the user
249 who is logging in. Alas, to reach higher directory levels you cannot
250 use /../, as the dots are interpreted by the browser and not actually
251 sent to the FTP server. To address this problem, the so called <dfn>Squid
252 %2f hack</dfn> was implemented in the Apache FTP proxy; it is a
253 solution which is also used by other popular proxy servers like the <a href="http://www.squid-cache.org/">Squid Proxy Cache</a>. By
254 prepending <code>/%2f</code> to the path of your request, you can make
255 such a proxy change the FTP starting directory to <code>/</code> (instead
256 of the home directory). For example, to retrieve the file
257 <code>/etc/motd</code>, you would use the URL:</p>
259 <div class="example"><p><code>
260 ftp://<var>user</var>@<var>host</var>/%2f/etc/motd
264 <h3><a name="ftppass" id="ftppass">How can I hide the FTP cleartext password
265 in my browser's URL line?</a></h3>
266 <p>To log in to an FTP server by username and password, Apache uses
267 different strategies. In absense of a user name and password in the URL
268 altogether, Apache sends an anonymous login to the FTP server,
271 <div class="example"><p><code>
272 user: anonymous<br />
273 password: apache_proxy@
276 <p>This works for all popular FTP servers which are configured for
277 anonymous access.</p>
279 <p>For a personal login with a specific username, you can embed the user
280 name into the URL, like in:</p>
282 <div class="example"><p><code>
283 ftp://<var>username</var>@<var>host</var>/myfile
286 <p>If the FTP server asks for a password when given this username (which
287 it should), then Apache will reply with a <code>401</code> (Authorization
288 required) response, which causes the Browser to pop up the
289 username/password dialog. Upon entering the password, the connection
290 attempt is retried, and if successful, the requested resource is
291 presented. The advantage of this procedure is that your browser does not
292 display the password in cleartext (which it would if you had used</p>
294 <div class="example"><p><code>
295 ftp://<var>username</var>:<var>password</var>@<var>host</var>/myfile
298 <p>in the first place).</p>
300 <div class="note"><h3>Note</h3>
301 <p>The password which is transmitted in such a way is not encrypted on
302 its way. It travels between your browser and the Apache proxy server in
303 a base64-encoded cleartext string, and between the Apache proxy and the
304 FTP server as plaintext. You should therefore think twice before
305 accessing your FTP server via HTTP (or before accessing your personal
306 files via FTP at all!) When using unsecure channels, an eavesdropper
307 might intercept your password on its way.</p>
310 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
311 <div class="section">
312 <h2><a name="startup" id="startup">Slow Startup</a></h2>
313 <p>If you're using the <code class="directive"><a href="#proxyblock">ProxyBlock</a></code> directive, hostnames' IP addresses are looked up
314 and cached during startup for later match test. This may take a few
315 seconds (or more) depending on the speed with which the hostname lookups
317 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
318 <div class="section">
319 <h2><a name="intranet" id="intranet">Intranet Proxy</a></h2>
320 <p>An Apache proxy server situated in an intranet needs to forward
321 external requests through the company's firewall (for this, configure
322 the <code class="directive"><a href="#proxyremote">ProxyRemote</a></code> directive
323 to forward the respective <var>scheme</var> to the firewall proxy).
324 However, when it has to
325 access resources within the intranet, it can bypass the firewall when
326 accessing hosts. The <code class="directive"><a href="#noproxy">NoProxy</a></code>
327 directive is useful for specifying which hosts belong to the intranet and
328 should be accessed directly.</p>
330 <p>Users within an intranet tend to omit the local domain name from their
331 WWW requests, thus requesting "http://somehost/" instead of
332 <code>http://somehost.example.com/</code>. Some commercial proxy servers
333 let them get away with this and simply serve the request, implying a
334 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
335 a redirect response and send the client to the correct, fully qualified,
336 server address. This is the preferred method since the user's bookmark
337 files will then contain fully qualified hosts.</p>
338 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
339 <div class="section">
340 <h2><a name="envsettings" id="envsettings">Protocol Adjustments</a></h2>
341 <p>For circumstances where you have a application server which doesn't
342 implement keepalives or HTTP/1.1 properly, there are 2 environment
343 variables which when set send a HTTP/1.0 with no keepalive. These are set
344 via the <code class="directive"><a href="../mod/mod_env.html#setenv">SetEnv</a></code> directive.</p>
346 <p>These are the <code>force-proxy-request-1.0</code> and
347 <code>proxy-nokeepalive</code> notes.</p>
349 <div class="example"><p><code>
350 <Location /buggyappserver/><br />
351 <span class="indent">
352 ProxyPass http://buggyappserver:7001/foo/<br />
353 SetEnv force-proxy-request-1.0 1<br />
354 SetEnv proxy-nokeepalive 1<br />
359 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
360 <div class="directive-section"><h2><a name="AllowCONNECT" id="AllowCONNECT">AllowCONNECT</a> <a name="allowconnect" id="allowconnect">Directive</a></h2>
361 <table class="directive">
362 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Ports that are allowed to CONNECT through the
364 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>AllowCONNECT <var>port</var> [<var>port</var>] ...</code></td></tr>
365 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>AllowCONNECT 443 563</code></td></tr>
366 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
367 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
368 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
370 <p>The <code class="directive">AllowCONNECT</code> directive specifies a list
371 of port numbers to which the proxy <code>CONNECT</code> method may
372 connect. Today's browsers use this method when a <code>https</code>
373 connection is requested and proxy tunneling over HTTP is in effect.</p>
375 <p>By default, only the default https port (<code>443</code>) and the
376 default snews port (<code>563</code>) are enabled. Use the
377 <code class="directive">AllowCONNECT</code> directive to override this default and
378 allow connections to the listed ports only.</p>
380 <p>Note that you'll need to have <code class="module"><a href="../mod/mod_proxy_connect.html">mod_proxy_connect</a></code> present
381 in the server in order to get the support for the <code>CONNECT</code> at
385 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
386 <div class="directive-section"><h2><a name="NoProxy" id="NoProxy">NoProxy</a> <a name="noproxy" id="noproxy">Directive</a></h2>
387 <table class="directive">
388 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Hosts, domains, or networks that will be connected to
390 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>NoProxy <var>host</var> [<var>host</var>] ...</code></td></tr>
391 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
392 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
393 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
395 <p>This directive is only useful for Apache proxy servers within
396 intranets. The <code class="directive">NoProxy</code> directive specifies a
397 list of subnets, IP addresses, hosts and/or domains, separated by
398 spaces. A request to a host which matches one or more of these is
399 always served directly, without forwarding to the configured
400 <code class="directive"><a href="#proxyremote">ProxyRemote</a></code> proxy server(s).</p>
402 <div class="example"><h3>Example</h3><p><code>
403 ProxyRemote * http://firewall.mycompany.com:81<br />
404 NoProxy .mycompany.com 192.168.112.0/21
407 <p>The <var>host</var> arguments to the <code class="directive">NoProxy</code>
408 directive are one of the following type list:</p>
412 <dt><var><a name="domain" id="domain">Domain</a></var></dt>
414 <p>A <dfn>Domain</dfn> is a partially qualified DNS domain name, preceded
415 by a period. It represents a list of hosts which logically belong to the
416 same DNS domain or zone (<em>i.e.</em>, the suffixes of the hostnames are
417 all ending in <var>Domain</var>).</p>
419 <div class="example"><h3>Examples</h3><p><code>
423 <p>To distinguish <var>Domain</var>s from <var><a href="#hostname">Hostname</a></var>s (both syntactically and semantically; a DNS domain can
424 have a DNS A record, too!), <var>Domain</var>s are always written with a
427 <div class="note"><h3>Note</h3>
428 <p>Domain name comparisons are done without regard to the case, and
429 <var>Domain</var>s are always assumed to be anchored in the root of the
430 DNS tree, therefore two domains <code>.MyDomain.com</code> and
431 <code>.mydomain.com.</code> (note the trailing period) are considered
432 equal. Since a domain comparison does not involve a DNS lookup, it is much
433 more efficient than subnet comparison.</p>
437 <dt><var><a name="subnet" id="subnet">SubNet</a></var></dt>
439 <p>A <dfn>SubNet</dfn> is a partially qualified internet address in
440 numeric (dotted quad) form, optionally followed by a slash and the netmask,
441 specified as the number of significant bits in the <var>SubNet</var>. It is
442 used to represent a subnet of hosts which can be reached over a common
443 network interface. In the absence of the explicit net mask it is assumed
444 that omitted (or zero valued) trailing digits specify the mask. (In this
445 case, the netmask can only be multiples of 8 bits wide.) Examples:</p>
448 <dt><code>192.168</code> or <code>192.168.0.0</code></dt>
449 <dd>the subnet 192.168.0.0 with an implied netmask of 16 valid bits
450 (sometimes used in the netmask form <code>255.255.0.0</code>)</dd>
451 <dt><code>192.168.112.0/21</code></dt>
452 <dd>the subnet <code>192.168.112.0/21</code> with a netmask of 21
453 valid bits (also used in the form <code>255.255.248.0</code>)</dd>
456 <p>As a degenerate case, a <em>SubNet</em> with 32 valid bits is the
457 equivalent to an <var><a href="#ipadr">IPAddr</a></var>, while a <var>SubNet</var> with zero
458 valid bits (<em>e.g.</em>, 0.0.0.0/0) is the same as the constant
459 <var>_Default_</var>, matching any IP address.</p></dd>
462 <dt><var><a name="ipaddr" id="ipaddr">IPAddr</a></var></dt>
464 <p>A <dfn>IPAddr</dfn> represents a fully qualified internet address in
465 numeric (dotted quad) form. Usually, this address represents a host, but
466 there need not necessarily be a DNS domain name connected with the
468 <div class="example"><h3>Example</h3><p><code>
472 <div class="note"><h3>Note</h3>
473 <p>An <var>IPAddr</var> does not need to be resolved by the DNS system, so
474 it can result in more effective apache performance.</p>
478 <dt><var><a name="hostname" id="hostname">Hostname</a></var></dt>
480 <p>A <dfn>Hostname</dfn> is a fully qualified DNS domain name which can
481 be resolved to one or more <var><a href="#ipaddr">IPAddrs</a></var> via the
482 DNS domain name service. It represents a logical host (in contrast to
483 <var><a href="#domain">Domain</a></var>s, see above) and must be resolvable
484 to at least one <var><a href="#ipaddr">IPAddr</a></var> (or often to a list
485 of hosts with different <var><a href="#ipaddr">IPAddr</a></var>s).</p>
487 <div class="example"><h3>Examples</h3><p><code>
488 prep.ai.mit.edu<br />
492 <div class="note"><h3>Note</h3>
493 <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
494 DNS lookup can be avoided. Name resolution in Apache can take a remarkable
495 deal of time when the connection to the name server uses a slow PPP
497 <p><var>Hostname</var> comparisons are done without regard to the case,
498 and <var>Hostname</var>s are always assumed to be anchored in the root
499 of the DNS tree, therefore two hosts <code>WWW.MyDomain.com</code>
500 and <code>www.mydomain.com.</code> (note the trailing period) are
501 considered equal.</p>
507 <li><a href="../dns-caveats.html">DNS Issues</a></li>
510 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
511 <div class="directive-section"><h2><a name="Proxy" id="Proxy"><Proxy></a> <a name="proxy" id="proxy">Directive</a></h2>
512 <table class="directive">
513 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Container for directives applied to proxied resources</td></tr>
514 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Proxy <var>wildcard-url</var>> ...</Proxy></code></td></tr>
515 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
516 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
517 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
519 <p>Directives placed in <code class="directive"><Proxy></code>
520 sections apply only to matching proxied content. Shell-style wildcards are
523 <p>For example, the following will allow only hosts in
524 <code>yournetwork.example.com</code> to access content via your proxy
527 <div class="example"><p><code>
528 <Proxy *><br />
529 <span class="indent">
530 Order Deny,Allow<br />
532 Allow from yournetwork.example.com<br />
537 <p>The following example will process all files in the <code>foo</code>
538 directory of <code>example.com</code> through the <code>INCLUDES</code>
539 filter when they are sent through the proxy server:</p>
541 <div class="example"><p><code>
542 <Proxy http://example.com/foo/*><br />
543 <span class="indent">
544 SetOutputFilter INCLUDES<br />
550 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
551 <div class="directive-section"><h2><a name="ProxyBadHeader" id="ProxyBadHeader">ProxyBadHeader</a> <a name="proxybadheader" id="proxybadheader">Directive</a></h2>
552 <table class="directive">
553 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determines how to handle bad header lines in a
555 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyBadHeader IsError|Ignore|StartBody</code></td></tr>
556 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyBadHeader IsError</code></td></tr>
557 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
558 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
559 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
560 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>available in Apache 2.0.44 and later</td></tr>
562 <p>The <code class="directive">ProxyBadHeader</code> directive determines the
563 behaviour of <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> if it receives syntactically invalid
564 header lines (<em>i.e.</em> containing no colon). The following arguments
568 <dt><code>IsError</code></dt>
569 <dd>Abort the request and end up with a 502 (Bad Gateway) response. This is
570 the default behaviour.</dd>
572 <dt><code>Ignore</code></dt>
573 <dd>Treat bad header lines as if they weren't sent.</dd>
575 <dt><code>StartBody</code></dt>
576 <dd>When receiving the first bad header line, finish reading the headers and
577 treat the remainder as body. This helps to work around buggy backend servers
578 which forget to insert an empty line between the headers and the body.</dd>
582 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
583 <div class="directive-section"><h2><a name="ProxyBlock" id="ProxyBlock">ProxyBlock</a> <a name="proxyblock" id="proxyblock">Directive</a></h2>
584 <table class="directive">
585 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Words, hosts, or domains that are banned from being
587 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyBlock *|<var>word</var>|<var>host</var>|<var>domain</var>
588 [<var>word</var>|<var>host</var>|<var>domain</var>] ...</code></td></tr>
589 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
590 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
591 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
593 <p>The <code class="directive">ProxyBlock</code> directive specifies a list of
594 words, hosts and/or domains, separated by spaces. HTTP, HTTPS, and
595 FTP document requests to sites whose names contain matched words,
596 hosts or domains are <em>blocked</em> by the proxy server. The proxy
597 module will also attempt to determine IP addresses of list items which
598 may be hostnames during startup, and cache them for match test as
599 well. That may slow down the startup time of the server.</p>
601 <div class="example"><h3>Example</h3><p><code>
602 ProxyBlock joes-garage.com some-host.co.uk rocky.wotsamattau.edu
605 <p><code>rocky.wotsamattau.edu</code> would also be matched if referenced by
608 <p>Note that <code>wotsamattau</code> would also be sufficient to match
609 <code>wotsamattau.edu</code>.</p>
611 <p>Note also that</p>
613 <div class="example"><p><code>
617 <p>blocks connections to all sites.</p>
620 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
621 <div class="directive-section"><h2><a name="ProxyDomain" id="ProxyDomain">ProxyDomain</a> <a name="proxydomain" id="proxydomain">Directive</a></h2>
622 <table class="directive">
623 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Default domain name for proxied requests</td></tr>
624 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyDomain <var>Domain</var></code></td></tr>
625 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
626 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
627 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
629 <p>This directive is only useful for Apache proxy servers within
630 intranets. The <code class="directive">ProxyDomain</code> directive specifies
631 the default domain which the apache proxy server will belong to. If a
632 request to a host without a domain name is encountered, a redirection
633 response to the same host with the configured <var>Domain</var> appended
634 will be generated.</p>
636 <div class="example"><h3>Example</h3><p><code>
637 ProxyRemote * http://firewall.mycompany.com:81<br />
638 NoProxy .mycompany.com 192.168.112.0/21<br />
639 ProxyDomain .mycompany.com
643 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
644 <div class="directive-section"><h2><a name="ProxyErrorOverride" id="ProxyErrorOverride">ProxyErrorOverride</a> <a name="proxyerroroverride" id="proxyerroroverride">Directive</a></h2>
645 <table class="directive">
646 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Override error pages for proxied content</td></tr>
647 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyErrorOverride On|Off</code></td></tr>
648 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyErrorOverride Off</code></td></tr>
649 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
650 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
651 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
652 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in version 2.0 and later</td></tr>
654 <p>This directive is useful for reverse-proxy setups, where you want to
655 have a common look and feel on the error pages seen by the end user.
656 This also allows for included files (via
657 <code class="module"><a href="../mod/mod_include.html">mod_include</a></code>'s SSI) to get
658 the error code and act accordingly (default behavior would display
659 the error page of the proxied server, turning this on shows the SSI
663 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
664 <div class="directive-section"><h2><a name="ProxyIOBufferSize" id="ProxyIOBufferSize">ProxyIOBufferSize</a> <a name="proxyiobuffersize" id="proxyiobuffersize">Directive</a></h2>
665 <table class="directive">
666 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determine size of internal data throughput buffer</td></tr>
667 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyIOBufferSize <var>bytes</var></code></td></tr>
668 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyIOBufferSize 8192</code></td></tr>
669 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
670 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
671 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
673 <p>The <code class="directive">ProxyIOBufferSize</code> directive adjusts the size
674 of the internal buffer, which is used as a scratchpad for the data between
675 input and output. The size must be less or equal <code>8192</code>.</p>
677 <p>In almost every case there's no reason to change that value.</p>
680 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
681 <div class="directive-section"><h2><a name="ProxyMatch" id="ProxyMatch"><ProxyMatch></a> <a name="proxymatch" id="proxymatch">Directive</a></h2>
682 <table class="directive">
683 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Container for directives applied to regular-expression-matched
684 proxied resources</td></tr>
685 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><ProxyMatch <var>regex</var>> ...</ProxyMatch></code></td></tr>
686 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
687 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
688 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
690 <p>The <code class="directive"><ProxyMatch></code> directive is
691 identical to the <code class="directive"><a href="#proxy"><Proxy></a></code> directive, except it matches URLs
692 using regular expressions.</p>
695 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
696 <div class="directive-section"><h2><a name="ProxyMaxForwards" id="ProxyMaxForwards">ProxyMaxForwards</a> <a name="proxymaxforwards" id="proxymaxforwards">Directive</a></h2>
697 <table class="directive">
698 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximium number of proxies that a request can be forwarded
700 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyMaxForwards <var>number</var></code></td></tr>
701 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyMaxForwards 10</code></td></tr>
702 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
703 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
704 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
705 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0 and later</td></tr>
707 <p>The <code class="directive">ProxyMaxForwards</code> directive specifies the
708 maximum number of proxies through which a request may pass, if there's no
709 <code>Max-Forwards</code> header supplied with the request. This is
710 set to prevent infinite proxy loops, or a DoS attack.</p>
712 <div class="example"><h3>Example</h3><p><code>
717 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
718 <div class="directive-section"><h2><a name="ProxyPass" id="ProxyPass">ProxyPass</a> <a name="proxypass" id="proxypass">Directive</a></h2>
719 <table class="directive">
720 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maps remote servers into the local server URL-space</td></tr>
721 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPass [<var>path</var>] !|<var>url</var></code></td></tr>
722 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
723 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
724 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
726 <p>This directive allows remote servers to be mapped into the space of
727 the local server; the local server does not act as a proxy in the
728 conventional sense, but appears to be a mirror of the remote
729 server. <var>path</var> is the name of a local virtual path; <var>url</var>
730 is a partial URL for the remote server and cannot include a query
733 <p>Suppose the local server has address <code>http://example.com/</code>;
736 <div class="example"><p><code>
737 ProxyPass /mirror/foo/ http://backend.example.com/
740 <p>will cause a local request for
741 <code>http://example.com/mirror/foo/bar</code> to be internally converted
742 into a proxy request to <code>http://backend.example.com/bar</code>.</p>
744 <p>The <code>!</code> directive is useful in situations where you don't want
745 to reverse-proxy a subdirectory, <em>e.g.</em></p>
747 <div class="example"><p><code>
748 ProxyPass /mirror/foo/i !<br />
749 ProxyPass /mirror/foo http://backend.example.com
752 <p>will proxy all requests to <code>/mirror/foo</code> to
753 <code>backend.example.com</code> <em>except</em> requests made to
754 <code>/mirror/foo/i</code>.</p>
756 <div class="note"><h3>Note</h3>
757 <p>Order is important. you need to put the exclusions <em>before</em> the
758 general <code class="directive">ProxyPass</code> directive.</p>
761 <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
762 directory is obtained from the <code class="directive"><a href="../mod/core.html#location"><Location></a></code>.</p>
764 <div class="warning">The <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive should
765 usually be set <strong>off</strong> when using
766 <code class="directive">ProxyPass</code>.</div>
768 <p>If you require a more flexible reverse-proxy configuration, see the
769 <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> directive with the
770 <code>[P]</code> flag.</p>
773 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
774 <div class="directive-section"><h2><a name="ProxyPassReverse" id="ProxyPassReverse">ProxyPassReverse</a> <a name="proxypassreverse" id="proxypassreverse">Directive</a></h2>
775 <table class="directive">
776 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Adjusts the URL in HTTP response headers sent from a reverse
777 proxied server</td></tr>
778 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPassReverse [<var>path</var>] <var>url</var></code></td></tr>
779 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
780 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
781 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
783 <p>This directive lets Apache adjust the URL in the <code>Location</code>,
784 <code>Content-Location</code> and <code>URI</code> headers on HTTP redirect
785 responses. This is essential when Apache is used as a reverse proxy to avoid
786 by-passing the reverse proxy because of HTTP redirects on the backend
787 servers which stay behind the reverse proxy.</p>
789 <p>Only the HTTP response headers specifically mentioned above
790 will be rewritten. Apache will not rewrite other response
791 headers, nor will it rewrite URL references inside HTML pages.
792 This means that if the proxied content contains absolute URL
793 references, they will by-pass the proxy. A third-party module
794 that will look inside the HTML and rewrite URL references is Nick
795 Kew's <a href="http://apache.webthing.com/software/mod_proxy_html/">mod_proxy_html</a>.</p>
797 <p><var>path</var> is the name of a local virtual path. <var>url</var> is a
798 partial URL for the remote server - the same way they are used for the
799 <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.</p>
801 <p>For example, suppose the local server has address
802 <code>http://example.com/</code>; then</p>
804 <div class="example"><p><code>
805 ProxyPass /mirror/foo/ http://backend.example.com/<br />
806 ProxyPassReverse /mirror/foo/ http://backend.example.com/<br />
807 ProxyPassReverseCookieDomain backend.example.com public.example.com<br />
808 ProxyPassReverseCookiePath / /mirror/foo/
811 <p>will not only cause a local request for the
812 <code>http://example.com/mirror/foo/bar</code> to be internally converted
813 into a proxy request to <code>http://backend.example.com/bar</code>
814 (the functionality <code>ProxyPass</code> provides here). It also takes care
815 of redirects the server <code>backend.example.com</code> sends: when
816 <code>http://backend.example.com/bar</code> is redirected by him to
817 <code>http://backend.example.com/quux</code> Apache adjusts this to
818 <code>http://example.com/mirror/foo/quux</code> before forwarding the HTTP
819 redirect response to the client. Note that the hostname used for
820 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>
822 <p>Note that this <code class="directive">ProxyPassReverse</code> directive can
823 also be used in conjunction with the proxy pass-through feature
824 (<code>RewriteRule ... [P]</code>) from <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>
825 because its doesn't depend on a corresponding <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.</p>
827 <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
828 directory is obtained from the <code class="directive"><a href="../mod/core.html#location"><Location></a></code>.</p>
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="ProxyPassReverseCookieDomain" id="ProxyPassReverseCookieDomain">ProxyPassReverseCookieDomain</a> <a name="proxypassreversecookiedomain" id="proxypassreversecookiedomain">Directive</a></h2>
833 <table class="directive">
834 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Adjusts the Domain string in Set-Cookie headers from a reverse-
835 proxied server</td></tr>
836 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPassReverseCookieDomain <var>internal-domain</var> <var>public-domain</var></code></td></tr>
837 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
838 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
839 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
841 <p>Usage is basically similar to
842 <code class="directive"><a href="#proxypassreverse">ProxyPassReverse</a></code>, but instead of
843 rewriting headers that are a URL, this rewrites the <code>domain</code>
844 string in <code>Set-Cookie</code> headers.</p>
847 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
848 <div class="directive-section"><h2><a name="ProxyPassReverseCookiePath" id="ProxyPassReverseCookiePath">ProxyPassReverseCookiePath</a> <a name="proxypassreversecookiepath" id="proxypassreversecookiepath">Directive</a></h2>
849 <table class="directive">
850 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Adjusts the Path string in Set-Cookie headers from a reverse-
851 proxied server</td></tr>
852 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPassReverseCookiePath <var>internal-path</var> <var>public-path</var></code></td></tr>
853 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
854 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
855 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
857 <p>Usage is basically similar to
858 <code class="directive"><a href="#proxypassreverse">ProxyPassReverse</a></code>, but instead of
859 rewriting headers that are a URL, this rewrites the <code>path</code>
860 string in <code>Set-Cookie</code> headers.</p>
863 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
864 <div class="directive-section"><h2><a name="ProxyPreserveHost" id="ProxyPreserveHost">ProxyPreserveHost</a> <a name="proxypreservehost" id="proxypreservehost">Directive</a></h2>
865 <table class="directive">
866 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Use incoming Host HTTP request header for proxy
868 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPreserveHost On|Off</code></td></tr>
869 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyPreserveHost Off</code></td></tr>
870 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
871 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
872 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
873 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.31 and later.</td></tr>
875 <p>When enabled, this option will pass the Host: line from the incoming
876 request to the proxied host, instead of the hostname specified in the
877 <code class="directive">ProxyPass</code> line.</p>
879 <p>This option should normally be turned <code>Off</code>. It is mostly
880 useful in special configurations like proxied mass name-based virtual
881 hosting, where the original Host header needs to be evaluated by the
885 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
886 <div class="directive-section"><h2><a name="ProxyReceiveBufferSize" id="ProxyReceiveBufferSize">ProxyReceiveBufferSize</a> <a name="proxyreceivebuffersize" id="proxyreceivebuffersize">Directive</a></h2>
887 <table class="directive">
888 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Network buffer size for proxied HTTP and FTP
889 connections</td></tr>
890 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyReceiveBufferSize <var>bytes</var></code></td></tr>
891 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyReceiveBufferSize 0</code></td></tr>
892 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
893 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
894 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
896 <p>The <code class="directive">ProxyReceiveBufferSize</code> directive specifies an
897 explicit (TCP/IP) network buffer size for proxied HTTP and FTP connections,
898 for increased throughput. It has to be greater than <code>512</code> or set
899 to <code>0</code> to indicate that the system's default buffer size should
902 <div class="example"><h3>Example</h3><p><code>
903 ProxyReceiveBufferSize 2048
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="ProxyRemote" id="ProxyRemote">ProxyRemote</a> <a name="proxyremote" id="proxyremote">Directive</a></h2>
909 <table class="directive">
910 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Remote proxy used to handle certain requests</td></tr>
911 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRemote <var>match</var> <var>remote-server</var></code></td></tr>
912 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
913 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
914 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
916 <p>This defines remote proxies to this proxy. <var>match</var> is either the
917 name of a URL-scheme that the remote server supports, or a partial URL
918 for which the remote server should be used, or <code>*</code> to indicate
919 the server should be contacted for all requests. <var>remote-server</var> is
920 a partial URL for the remote server. Syntax:</p>
922 <div class="example"><p><code>
923 <dfn>remote-server</dfn> =
924 <var>scheme</var>://<var>hostname</var>[:<var>port</var>]
927 <p><var>scheme</var> is effectively the protocol that should be used to
928 communicate with the remote server; only <code>http</code> is supported by
931 <div class="example"><h3>Example</h3><p><code>
932 ProxyRemote http://goodguys.com/ http://mirrorguys.com:8000<br />
933 ProxyRemote * http://cleversite.com<br />
934 ProxyRemote ftp http://ftpproxy.mydomain.com:8080
937 <p>In the last example, the proxy will forward FTP requests, encapsulated
938 as yet another HTTP proxy request, to another proxy which can handle
941 <p>This option also supports reverse proxy configuration - a backend
942 webserver can be embedded within a virtualhost URL space even if that
943 server is hidden by another forward proxy.</p>
946 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
947 <div class="directive-section"><h2><a name="ProxyRemoteMatch" id="ProxyRemoteMatch">ProxyRemoteMatch</a> <a name="proxyremotematch" id="proxyremotematch">Directive</a></h2>
948 <table class="directive">
949 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Remote proxy used to handle requests matched by regular
950 expressions</td></tr>
951 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRemoteMatch <var>regex</var> <var>remote-server</var></code></td></tr>
952 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
953 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
954 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
956 <p>The <code class="directive">ProxyRemoteMatch</code> is identical to the
957 <code class="directive"><a href="#proxyremote">ProxyRemote</a></code> directive, except the
958 first argument is a regular expression match against the requested URL.</p>
961 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
962 <div class="directive-section"><h2><a name="ProxyRequests" id="ProxyRequests">ProxyRequests</a> <a name="proxyrequests" id="proxyrequests">Directive</a></h2>
963 <table class="directive">
964 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables forward (standard) proxy requests</td></tr>
965 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRequests On|Off</code></td></tr>
966 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyRequests Off</code></td></tr>
967 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
968 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
969 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
971 <p>This allows or prevents Apache from functioning as a forward proxy
972 server. (Setting ProxyRequests to <code>Off</code> does not disable use of
973 the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.)</p>
975 <p>In a typical reverse proxy configuration, this option should be set to
976 <code>Off</code>.</p>
978 <p>In order to get the functionality of proxying HTTP or FTP sites, you
979 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>
980 (or both) present in the server.</p>
982 <div class="warning"><h3>Warning</h3>
983 <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
984 both to your network and to the Internet at large.</p>
988 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
989 <div class="directive-section"><h2><a name="ProxyTimeout" id="ProxyTimeout">ProxyTimeout</a> <a name="proxytimeout" id="proxytimeout">Directive</a></h2>
990 <table class="directive">
991 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Network timeout for proxied requests</td></tr>
992 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyTimeout <var>seconds</var></code></td></tr>
993 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyTimeout 300</code></td></tr>
994 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
995 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
996 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
997 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.31 and later</td></tr>
999 <p>This directive allows a user to specifiy a timeout on proxy requests.
1000 This is useful when you have a slow/buggy appserver which hangs, and you
1001 would rather just return a timeout and fail gracefully instead of waiting
1002 however long it takes the server to return.</p>
1005 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1006 <div class="directive-section"><h2><a name="ProxyVia" id="ProxyVia">ProxyVia</a> <a name="proxyvia" id="proxyvia">Directive</a></h2>
1007 <table class="directive">
1008 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Information provided in the Via HTTP response
1009 header for proxied requests</td></tr>
1010 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyVia On|Off|Full|Block</code></td></tr>
1011 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyVia Off</code></td></tr>
1012 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1013 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1014 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1016 <p>This directive controls the use of the <code>Via:</code> HTTP
1017 header by the proxy. Its intended use is to control the flow of
1018 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
1019 14.45 for an explanation of <code>Via:</code> header lines.</p>
1022 <li>If set to <code>Off</code>, which is the default, no special processing
1023 is performed. If a request or reply contains a <code>Via:</code> header,
1024 it is passed through unchanged.</li>
1026 <li>If set to <code>On</code>, each request and reply will get a
1027 <code>Via:</code> header line added for the current host.</li>
1029 <li>If set to <code>Full</code>, each generated <code>Via:</code> header
1030 line will additionally have the Apache server version shown as a
1031 <code>Via:</code> comment field.</li>
1033 <li>If set to <code>Block</code>, every proxy request will have all its
1034 <code>Via:</code> header lines removed. No new <code>Via:</code> header will
1040 <div class="bottomlang">
1041 <p><span>Available Languages: </span><a href="../en/mod/mod_proxy.html" title="English"> en </a></p>
1042 </div><div id="footer">
1043 <p class="apache">Copyright 1999-2004 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>
1044 <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>