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16 <p class="apache">Apache HTTP Server Version 2.3</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> |
25 <a href="../fr/mod/mod_proxy.html" hreflang="fr" rel="alternate" title="Français"> fr </a> |
26 <a href="../ja/mod/mod_proxy.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a></p>
28 <table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>HTTP/1.1 proxy/gateway server</td></tr>
29 <tr><th><a href="module-dict.html#Status">Status:</a></th><td>Extension</td></tr>
30 <tr><th><a href="module-dict.html#ModuleIdentifier">Module Identifier:</a></th><td>proxy_module</td></tr>
31 <tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>mod_proxy.c</td></tr></table>
34 <div class="warning"><h3>Warning</h3>
35 <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
36 network and to the Internet at large.</p>
39 <p>This module implements a proxy/gateway for Apache. It implements
40 proxying capability for <code>AJP13</code> (Apache JServe Protocol
41 version 1.3), <code>FTP</code>, <code>CONNECT</code> (for SSL),
42 <code>HTTP/0.9</code>, <code>HTTP/1.0</code>, and <code>HTTP/1.1</code>.
43 The module can be configured to connect to other proxy modules for these
44 and other protocols.</p>
46 <p>Apache's proxy features are divided into several modules in
47 addition to <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>:
48 <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>,
49 <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>,
50 and <code class="module"><a href="../mod/mod_proxy_connect.html">mod_proxy_connect</a></code>. Thus, if you want to use
51 one or more of the particular proxy functions, load
52 <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> <em>and</em> the appropriate module(s)
53 into the server (either statically at compile-time or dynamically
54 via the <code class="directive"><a href="../mod/mod_so.html#loadmodule">LoadModule</a></code>
57 <p>In addition, extended features are provided by other modules.
58 Caching is provided by <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code> and related
59 modules. The ability to contact remote servers using the SSL/TLS
60 protocol is provided by the <code>SSLProxy*</code> directives of
61 <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code>. These additional modules will need
62 to be loaded and configured to take advantage of these features.</p>
64 <div id="quickview"><h3 class="directives">Directives</h3>
66 <li><img alt="" src="../images/down.gif" /> <a href="#balancermember">BalancerMember</a></li>
67 <li><img alt="" src="../images/down.gif" /> <a href="#noproxy">NoProxy</a></li>
68 <li><img alt="" src="../images/down.gif" /> <a href="#proxy"><Proxy></a></li>
69 <li><img alt="" src="../images/down.gif" /> <a href="#proxybadheader">ProxyBadHeader</a></li>
70 <li><img alt="" src="../images/down.gif" /> <a href="#proxyblock">ProxyBlock</a></li>
71 <li><img alt="" src="../images/down.gif" /> <a href="#proxydomain">ProxyDomain</a></li>
72 <li><img alt="" src="../images/down.gif" /> <a href="#proxyerroroverride">ProxyErrorOverride</a></li>
73 <li><img alt="" src="../images/down.gif" /> <a href="#proxyiobuffersize">ProxyIOBufferSize</a></li>
74 <li><img alt="" src="../images/down.gif" /> <a href="#proxymatch"><ProxyMatch></a></li>
75 <li><img alt="" src="../images/down.gif" /> <a href="#proxymaxforwards">ProxyMaxForwards</a></li>
76 <li><img alt="" src="../images/down.gif" /> <a href="#proxypass">ProxyPass</a></li>
77 <li><img alt="" src="../images/down.gif" /> <a href="#proxypassinterpolateenv">ProxyPassInterpolateEnv</a></li>
78 <li><img alt="" src="../images/down.gif" /> <a href="#proxypassmatch">ProxyPassMatch</a></li>
79 <li><img alt="" src="../images/down.gif" /> <a href="#proxypassreverse">ProxyPassReverse</a></li>
80 <li><img alt="" src="../images/down.gif" /> <a href="#proxypassreversecookiedomain">ProxyPassReverseCookieDomain</a></li>
81 <li><img alt="" src="../images/down.gif" /> <a href="#proxypassreversecookiepath">ProxyPassReverseCookiePath</a></li>
82 <li><img alt="" src="../images/down.gif" /> <a href="#proxypreservehost">ProxyPreserveHost</a></li>
83 <li><img alt="" src="../images/down.gif" /> <a href="#proxyreceivebuffersize">ProxyReceiveBufferSize</a></li>
84 <li><img alt="" src="../images/down.gif" /> <a href="#proxyremote">ProxyRemote</a></li>
85 <li><img alt="" src="../images/down.gif" /> <a href="#proxyremotematch">ProxyRemoteMatch</a></li>
86 <li><img alt="" src="../images/down.gif" /> <a href="#proxyrequests">ProxyRequests</a></li>
87 <li><img alt="" src="../images/down.gif" /> <a href="#proxyset">ProxySet</a></li>
88 <li><img alt="" src="../images/down.gif" /> <a href="#proxystatus">ProxyStatus</a></li>
89 <li><img alt="" src="../images/down.gif" /> <a href="#proxytimeout">ProxyTimeout</a></li>
90 <li><img alt="" src="../images/down.gif" /> <a href="#proxyvia">ProxyVia</a></li>
94 <li><img alt="" src="../images/down.gif" /> <a href="#forwardreverse">Forward Proxies and Reverse
95 Proxies/Gateways</a></li>
96 <li><img alt="" src="../images/down.gif" /> <a href="#examples">Basic Examples</a></li>
97 <li><img alt="" src="../images/down.gif" /> <a href="#access">Controlling access to your proxy</a></li>
98 <li><img alt="" src="../images/down.gif" /> <a href="#startup">Slow Startup</a></li>
99 <li><img alt="" src="../images/down.gif" /> <a href="#intranet">Intranet Proxy</a></li>
100 <li><img alt="" src="../images/down.gif" /> <a href="#envsettings">Protocol Adjustments</a></li>
101 <li><img alt="" src="../images/down.gif" /> <a href="#request-bodies">Request Bodies</a></li>
102 <li><img alt="" src="../images/down.gif" /> <a href="#x-headers">Reverse Proxy Request Headers</a></li>
103 </ul><h3>See also</h3>
105 <li><code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code></li>
106 <li><code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code></li>
107 <li><code class="module"><a href="../mod/mod_proxy_ftp.html">mod_proxy_ftp</a></code></li>
108 <li><code class="module"><a href="../mod/mod_proxy_connect.html">mod_proxy_connect</a></code></li>
109 <li><code class="module"><a href="../mod/mod_proxy_balancer.html">mod_proxy_balancer</a></code></li>
110 <li><code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code></li>
112 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
113 <div class="section">
114 <h2><a name="forwardreverse" id="forwardreverse">Forward Proxies and Reverse
115 Proxies/Gateways</a></h2>
116 <p>Apache can be configured in both a <dfn>forward</dfn> and
117 <dfn>reverse</dfn> proxy (also known as <dfn>gateway</dfn>) mode.</p>
119 <p>An ordinary <dfn>forward proxy</dfn> is an intermediate
120 server that sits between the client and the <em>origin
121 server</em>. In order to get content from the origin server,
122 the client sends a request to the proxy naming the origin server
123 as the target and the proxy then requests the content from the
124 origin server and returns it to the client. The client must be
125 specially configured to use the forward proxy to access other
128 <p>A typical usage of a forward proxy is to provide Internet
129 access to internal clients that are otherwise restricted by a
130 firewall. The forward proxy can also use caching (as provided
131 by <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code>) to reduce network usage.</p>
133 <p>The forward proxy is activated using the <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive. Because
134 forward proxies allow clients to access arbitrary sites through
135 your server and to hide their true origin, it is essential that
136 you <a href="#access">secure your server</a> so that only
137 authorized clients can access the proxy before activating a
140 <p>A <dfn>reverse proxy</dfn> (or <dfn>gateway</dfn>), by
141 contrast, appears to the client just like an ordinary web
142 server. No special configuration on the client is necessary.
143 The client makes ordinary requests for content in the name-space
144 of the reverse proxy. The reverse proxy then decides where to
145 send those requests, and returns the content as if it was itself
148 <p>A typical usage of a reverse proxy is to provide Internet
149 users access to a server that is behind a firewall. Reverse
150 proxies can also be used to balance load among several back-end
151 servers, or to provide caching for a slower back-end server.
152 In addition, reverse proxies can be used simply to bring
153 several servers into the same URL space.</p>
155 <p>A reverse proxy is activated using the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive or the
156 <code>[P]</code> flag to the <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> directive. It is
157 <strong>not</strong> necessary to turn <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> on in order to
158 configure a reverse proxy.</p>
159 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
160 <div class="section">
161 <h2><a name="examples" id="examples">Basic Examples</a></h2>
163 <p>The examples below are only a very basic idea to help you
164 get started. Please read the documentation on the individual
167 <p>In addition, if you wish to have caching enabled, consult
168 the documentation from <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code>.</p>
170 <div class="example"><h3>Forward Proxy</h3><p><code>
171 ProxyRequests On<br />
174 <Proxy *><br />
175 <span class="indent">
176 Order deny,allow<br />
178 Allow from internal.example.com<br />
183 <div class="example"><h3>Reverse Proxy</h3><p><code>
184 ProxyRequests Off<br />
186 <Proxy *><br />
187 <span class="indent">
188 Order deny,allow<br />
193 ProxyPass /foo http://foo.example.com/bar<br />
194 ProxyPassReverse /foo http://foo.example.com/bar
196 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
197 <div class="section">
198 <h2><a name="access" id="access">Controlling access to your proxy</a></h2>
199 <p>You can control who can access your proxy via the <code class="directive"><a href="#proxy"><Proxy></a></code> control block as in
200 the following example:</p>
202 <div class="example"><p><code>
203 <Proxy *><br />
204 <span class="indent">
205 Order Deny,Allow<br />
207 Allow from 192.168.0<br />
212 <p>For more information on access control directives, see
213 <code class="module"><a href="../mod/mod_authz_host.html">mod_authz_host</a></code>.</p>
215 <p>Strictly limiting access is essential if you are using a
216 forward proxy (using the <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive).
217 Otherwise, your server can be used by any client to access
218 arbitrary hosts while hiding his or her true identity. This is
219 dangerous both for your network and for the Internet at large.
220 When using a reverse proxy (using the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive with
221 <code>ProxyRequests Off</code>), access control is less
222 critical because clients can only contact the hosts that you
223 have specifically configured.</p>
225 <p><strong>See Also</strong> the <a href="mod_proxy_http.html#env">Proxy-Chain-Auth</a> environment variable.</p>
227 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
228 <div class="section">
229 <h2><a name="startup" id="startup">Slow Startup</a></h2>
230 <p>If you're using the <code class="directive"><a href="#proxyblock">ProxyBlock</a></code> directive, hostnames' IP addresses are looked up
231 and cached during startup for later match test. This may take a few
232 seconds (or more) depending on the speed with which the hostname lookups
234 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
235 <div class="section">
236 <h2><a name="intranet" id="intranet">Intranet Proxy</a></h2>
237 <p>An Apache proxy server situated in an intranet needs to forward
238 external requests through the company's firewall (for this, configure
239 the <code class="directive"><a href="#proxyremote">ProxyRemote</a></code> directive
240 to forward the respective <var>scheme</var> to the firewall proxy).
241 However, when it has to
242 access resources within the intranet, it can bypass the firewall when
243 accessing hosts. The <code class="directive"><a href="#noproxy">NoProxy</a></code>
244 directive is useful for specifying which hosts belong to the intranet and
245 should be accessed directly.</p>
247 <p>Users within an intranet tend to omit the local domain name from their
248 WWW requests, thus requesting "http://somehost/" instead of
249 <code>http://somehost.example.com/</code>. Some commercial proxy servers
250 let them get away with this and simply serve the request, implying a
251 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
252 a redirect response and send the client to the correct, fully qualified,
253 server address. This is the preferred method since the user's bookmark
254 files will then contain fully qualified hosts.</p>
255 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
256 <div class="section">
257 <h2><a name="envsettings" id="envsettings">Protocol Adjustments</a></h2>
258 <p>For circumstances where <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> is sending
259 requests to an origin server that doesn't properly implement
260 keepalives or HTTP/1.1, there are two <a href="../env.html">environment variables</a> that can force the
261 request to use HTTP/1.0 with no keepalive. These are set via the
262 <code class="directive"><a href="../mod/mod_env.html#setenv">SetEnv</a></code> directive.</p>
264 <p>These are the <code>force-proxy-request-1.0</code> and
265 <code>proxy-nokeepalive</code> notes.</p>
267 <div class="example"><p><code>
268 <Location /buggyappserver/><br />
269 <span class="indent">
270 ProxyPass http://buggyappserver:7001/foo/<br />
271 SetEnv force-proxy-request-1.0 1<br />
272 SetEnv proxy-nokeepalive 1<br />
277 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
278 <div class="section">
279 <h2><a name="request-bodies" id="request-bodies">Request Bodies</a></h2>
281 <p>Some request methods such as POST include a request body.
282 The HTTP protocol requires that requests which include a body
283 either use chunked transfer encoding or send a
284 <code>Content-Length</code> request header. When passing these
285 requests on to the origin server, <code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code>
286 will always attempt to send the <code>Content-Length</code>. But
287 if the body is large and the original request used chunked
288 encoding, then chunked encoding may also be used in the upstream
289 request. You can control this selection using <a href="../env.html">environment variables</a>. Setting
290 <code>proxy-sendcl</code> ensures maximum compatibility with
291 upstream servers by always sending the
292 <code>Content-Length</code>, while setting
293 <code>proxy-sendchunked</code> minimizes resource usage by using
294 chunked encoding.</p>
296 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
297 <div class="section">
298 <h2><a name="x-headers" id="x-headers">Reverse Proxy Request Headers</a></h2>
300 <p>When acting in a reverse-proxy mode (using the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive, for example),
301 <code class="module"><a href="../mod/mod_proxy_http.html">mod_proxy_http</a></code> adds several request headers in
302 order to pass information to the origin server. These headers
306 <dt><code>X-Forwarded-For</code></dt>
307 <dd>The IP address of the client.</dd>
308 <dt><code>X-Forwarded-Host</code></dt>
309 <dd>The original host requested by the client in the <code>Host</code>
310 HTTP request header.</dd>
311 <dt><code>X-Forwarded-Server</code></dt>
312 <dd>The hostname of the proxy server.</dd>
315 <p>Be careful when using these headers on the origin server, since
316 they will contain more than one (comma-separated) value if the
317 original request already contained one of these headers. For
318 example, you can use <code>%{X-Forwarded-For}i</code> in the log
319 format string of the origin server to log the original clients IP
320 address, but you may get more than one address if the request
321 passes through several proxies.</p>
323 <p>See also the <code class="directive"><a href="#proxypreservehost">ProxyPreserveHost</a></code> and <code class="directive"><a href="#proxyvia">ProxyVia</a></code> directives, which control
324 other request headers.</p>
327 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
328 <div class="directive-section"><h2><a name="BalancerMember" id="BalancerMember">BalancerMember</a> <a name="balancermember" id="balancermember">Directive</a></h2>
329 <table class="directive">
330 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Add a member to a load balancing group</td></tr>
331 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>BalancerMember [<var>balancerurl</var>] <var>url</var> [<var>key=value [key=value ...]]</var></code></td></tr>
332 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory</td></tr>
333 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
334 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
335 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>BalancerMember is only available in Apache 2.2
338 <p>This directive adds a member to a load balancing group. It could be used
339 within a <code><Proxy <var>balancer://</var>...></code> container
340 directive, and can take any of the key value pair parameters available to
341 <code class="directive"><a href="#proxypass">ProxyPass</a></code> directives.</p>
342 <p>One additional parameter is available only to <code class="directive"><a href="#balancermember">BalancerMember</a></code> directives:
343 <var>loadfactor</var>. This is the member load factor - a number between 1
344 (default) and 100, which defines the weighted load to be applied to the
345 member in question.</p>
346 <p>The balancerurl is only needed when not in <code><Proxy <var>balancer://</var>...></code>
347 container directive. It corresponds to the url of a balancer defined in
348 <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.</p>
351 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
352 <div class="directive-section"><h2><a name="NoProxy" id="NoProxy">NoProxy</a> <a name="noproxy" id="noproxy">Directive</a></h2>
353 <table class="directive">
354 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Hosts, domains, or networks that will be connected to
356 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>NoProxy <var>host</var> [<var>host</var>] ...</code></td></tr>
357 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
358 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
359 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
361 <p>This directive is only useful for Apache proxy servers within
362 intranets. The <code class="directive">NoProxy</code> directive specifies a
363 list of subnets, IP addresses, hosts and/or domains, separated by
364 spaces. A request to a host which matches one or more of these is
365 always served directly, without forwarding to the configured
366 <code class="directive"><a href="#proxyremote">ProxyRemote</a></code> proxy server(s).</p>
368 <div class="example"><h3>Example</h3><p><code>
369 ProxyRemote * http://firewall.example.com:81<br />
370 NoProxy .example.com 192.168.112.0/21
373 <p>The <var>host</var> arguments to the <code class="directive">NoProxy</code>
374 directive are one of the following type list:</p>
378 <dt><var><a name="domain" id="domain">Domain</a></var></dt>
380 <p>A <dfn>Domain</dfn> is a partially qualified DNS domain name, preceded
381 by a period. It represents a list of hosts which logically belong to the
382 same DNS domain or zone (<em>i.e.</em>, the suffixes of the hostnames are
383 all ending in <var>Domain</var>).</p>
385 <div class="example"><h3>Examples</h3><p><code>
389 <p>To distinguish <var>Domain</var>s from <var><a href="#hostname">Hostname</a></var>s (both syntactically and semantically; a DNS domain can
390 have a DNS A record, too!), <var>Domain</var>s are always written with a
393 <div class="note"><h3>Note</h3>
394 <p>Domain name comparisons are done without regard to the case, and
395 <var>Domain</var>s are always assumed to be anchored in the root of the
396 DNS tree, therefore two domains <code>.ExAmple.com</code> and
397 <code>.example.com.</code> (note the trailing period) are considered
398 equal. Since a domain comparison does not involve a DNS lookup, it is much
399 more efficient than subnet comparison.</p>
403 <dt><var><a name="subnet" id="subnet">SubNet</a></var></dt>
405 <p>A <dfn>SubNet</dfn> is a partially qualified internet address in
406 numeric (dotted quad) form, optionally followed by a slash and the netmask,
407 specified as the number of significant bits in the <var>SubNet</var>. It is
408 used to represent a subnet of hosts which can be reached over a common
409 network interface. In the absence of the explicit net mask it is assumed
410 that omitted (or zero valued) trailing digits specify the mask. (In this
411 case, the netmask can only be multiples of 8 bits wide.) Examples:</p>
414 <dt><code>192.168</code> or <code>192.168.0.0</code></dt>
415 <dd>the subnet 192.168.0.0 with an implied netmask of 16 valid bits
416 (sometimes used in the netmask form <code>255.255.0.0</code>)</dd>
417 <dt><code>192.168.112.0/21</code></dt>
418 <dd>the subnet <code>192.168.112.0/21</code> with a netmask of 21
419 valid bits (also used in the form <code>255.255.248.0</code>)</dd>
422 <p>As a degenerate case, a <em>SubNet</em> with 32 valid bits is the
423 equivalent to an <var><a href="#ipadr">IPAddr</a></var>, while a <var>SubNet</var> with zero
424 valid bits (<em>e.g.</em>, 0.0.0.0/0) is the same as the constant
425 <var>_Default_</var>, matching any IP address.</p></dd>
428 <dt><var><a name="ipaddr" id="ipaddr">IPAddr</a></var></dt>
430 <p>A <dfn>IPAddr</dfn> represents a fully qualified internet address in
431 numeric (dotted quad) form. Usually, this address represents a host, but
432 there need not necessarily be a DNS domain name connected with the
434 <div class="example"><h3>Example</h3><p><code>
438 <div class="note"><h3>Note</h3>
439 <p>An <var>IPAddr</var> does not need to be resolved by the DNS system, so
440 it can result in more effective apache performance.</p>
444 <dt><var><a name="hostname" id="hostname">Hostname</a></var></dt>
446 <p>A <dfn>Hostname</dfn> is a fully qualified DNS domain name which can
447 be resolved to one or more <var><a href="#ipaddr">IPAddrs</a></var> via the
448 DNS domain name service. It represents a logical host (in contrast to
449 <var><a href="#domain">Domain</a></var>s, see above) and must be resolvable
450 to at least one <var><a href="#ipaddr">IPAddr</a></var> (or often to a list
451 of hosts with different <var><a href="#ipaddr">IPAddr</a></var>s).</p>
453 <div class="example"><h3>Examples</h3><p><code>
454 prep.ai.example.com<br />
458 <div class="note"><h3>Note</h3>
459 <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
460 DNS lookup can be avoided. Name resolution in Apache can take a remarkable
461 deal of time when the connection to the name server uses a slow PPP
463 <p><var>Hostname</var> comparisons are done without regard to the case,
464 and <var>Hostname</var>s are always assumed to be anchored in the root
465 of the DNS tree, therefore two hosts <code>WWW.ExAmple.com</code>
466 and <code>www.example.com.</code> (note the trailing period) are
467 considered equal.</p>
473 <li><a href="../dns-caveats.html">DNS Issues</a></li>
476 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
477 <div class="directive-section"><h2><a name="Proxy" id="Proxy"><Proxy></a> <a name="proxy" id="proxy">Directive</a></h2>
478 <table class="directive">
479 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Container for directives applied to proxied resources</td></tr>
480 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><Proxy <var>wildcard-url</var>> ...</Proxy></code></td></tr>
481 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
482 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
483 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
485 <p>Directives placed in <code class="directive"><Proxy></code>
486 sections apply only to matching proxied content. Shell-style wildcards are
489 <p>For example, the following will allow only hosts in
490 <code>yournetwork.example.com</code> to access content via your proxy
493 <div class="example"><p><code>
494 <Proxy *><br />
495 <span class="indent">
496 Order Deny,Allow<br />
498 Allow from yournetwork.example.com<br />
503 <p>The following example will process all files in the <code>foo</code>
504 directory of <code>example.com</code> through the <code>INCLUDES</code>
505 filter when they are sent through the proxy server:</p>
507 <div class="example"><p><code>
508 <Proxy http://example.com/foo/*><br />
509 <span class="indent">
510 SetOutputFilter INCLUDES<br />
518 <li><code class="directive"><a href="#proxymatch"><ProxyMatch></a></code></li>
521 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
522 <div class="directive-section"><h2><a name="ProxyBadHeader" id="ProxyBadHeader">ProxyBadHeader</a> <a name="proxybadheader" id="proxybadheader">Directive</a></h2>
523 <table class="directive">
524 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determines how to handle bad header lines in a
526 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyBadHeader IsError|Ignore|StartBody</code></td></tr>
527 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyBadHeader IsError</code></td></tr>
528 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
529 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
530 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
531 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.44 and later</td></tr>
533 <p>The <code class="directive">ProxyBadHeader</code> directive determines the
534 behaviour of <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> if it receives syntactically invalid
535 header lines (<em>i.e.</em> containing no colon). The following arguments
539 <dt><code>IsError</code></dt>
540 <dd>Abort the request and end up with a 502 (Bad Gateway) response. This is
541 the default behaviour.</dd>
543 <dt><code>Ignore</code></dt>
544 <dd>Treat bad header lines as if they weren't sent.</dd>
546 <dt><code>StartBody</code></dt>
547 <dd>When receiving the first bad header line, finish reading the headers and
548 treat the remainder as body. This helps to work around buggy backend servers
549 which forget to insert an empty line between the headers and the body.</dd>
553 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
554 <div class="directive-section"><h2><a name="ProxyBlock" id="ProxyBlock">ProxyBlock</a> <a name="proxyblock" id="proxyblock">Directive</a></h2>
555 <table class="directive">
556 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Words, hosts, or domains that are banned from being
558 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyBlock *|<var>word</var>|<var>host</var>|<var>domain</var>
559 [<var>word</var>|<var>host</var>|<var>domain</var>] ...</code></td></tr>
560 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
561 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
562 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
564 <p>The <code class="directive">ProxyBlock</code> directive specifies a list of
565 words, hosts and/or domains, separated by spaces. HTTP, HTTPS, and
566 FTP document requests to sites whose names contain matched words,
567 hosts or domains are <em>blocked</em> by the proxy server. The proxy
568 module will also attempt to determine IP addresses of list items which
569 may be hostnames during startup, and cache them for match test as
570 well. That may slow down the startup time of the server.</p>
572 <div class="example"><h3>Example</h3><p><code>
573 ProxyBlock joes-garage.com some-host.co.uk rocky.wotsamattau.edu
576 <p><code>rocky.wotsamattau.edu</code> would also be matched if referenced by
579 <p>Note that <code>wotsamattau</code> would also be sufficient to match
580 <code>wotsamattau.edu</code>.</p>
582 <p>Note also that</p>
584 <div class="example"><p><code>
588 <p>blocks connections to all sites.</p>
591 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
592 <div class="directive-section"><h2><a name="ProxyDomain" id="ProxyDomain">ProxyDomain</a> <a name="proxydomain" id="proxydomain">Directive</a></h2>
593 <table class="directive">
594 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Default domain name for proxied requests</td></tr>
595 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyDomain <var>Domain</var></code></td></tr>
596 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
597 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
598 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
600 <p>This directive is only useful for Apache proxy servers within
601 intranets. The <code class="directive">ProxyDomain</code> directive specifies
602 the default domain which the apache proxy server will belong to. If a
603 request to a host without a domain name is encountered, a redirection
604 response to the same host with the configured <var>Domain</var> appended
605 will be generated.</p>
607 <div class="example"><h3>Example</h3><p><code>
608 ProxyRemote * http://firewall.example.com:81<br />
609 NoProxy .example.com 192.168.112.0/21<br />
610 ProxyDomain .example.com
614 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
615 <div class="directive-section"><h2><a name="ProxyErrorOverride" id="ProxyErrorOverride">ProxyErrorOverride</a> <a name="proxyerroroverride" id="proxyerroroverride">Directive</a></h2>
616 <table class="directive">
617 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Override error pages for proxied content</td></tr>
618 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyErrorOverride On|Off</code></td></tr>
619 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyErrorOverride Off</code></td></tr>
620 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
621 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
622 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
623 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in version 2.0 and later</td></tr>
625 <p>This directive is useful for reverse-proxy setups, where you want to
626 have a common look and feel on the error pages seen by the end user.
627 This also allows for included files (via
628 <code class="module"><a href="../mod/mod_include.html">mod_include</a></code>'s SSI) to get
629 the error code and act accordingly (default behavior would display
630 the error page of the proxied server, turning this on shows the SSI
633 <p>This directive does not affect the processing of informational (1xx),
634 normal success (2xx), or redirect (3xx) responses.</p>
637 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
638 <div class="directive-section"><h2><a name="ProxyIOBufferSize" id="ProxyIOBufferSize">ProxyIOBufferSize</a> <a name="proxyiobuffersize" id="proxyiobuffersize">Directive</a></h2>
639 <table class="directive">
640 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Determine size of internal data throughput buffer</td></tr>
641 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyIOBufferSize <var>bytes</var></code></td></tr>
642 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyIOBufferSize 8192</code></td></tr>
643 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
644 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
645 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
647 <p>The <code class="directive">ProxyIOBufferSize</code> directive adjusts the size
648 of the internal buffer, which is used as a scratchpad for the data between
649 input and output. The size must be at least <code>512</code>.</p>
651 <p>In almost every case there's no reason to change that value.</p>
652 <p>If used with AJP this directive sets the maximum AJP packet size in
653 bytes. If you change it from the default, you must also change the
654 <code>packetSize</code> attribute of your AJP connector on the
655 Tomcat side! The attribute <code>packetSize</code> is only available
656 in Tomcat <code>5.5.20+</code> and <code>6.0.2+</code></p>
657 <p>Normally it is not necessary to change the maximum packet size.
658 Problems with the default value have been reported when sending
659 certificates or certificate chains.</p>
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="ProxyMatch" id="ProxyMatch"><ProxyMatch></a> <a name="proxymatch" id="proxymatch">Directive</a></h2>
665 <table class="directive">
666 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Container for directives applied to regular-expression-matched
667 proxied resources</td></tr>
668 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code><ProxyMatch <var>regex</var>> ...</ProxyMatch></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"><ProxyMatch></code> directive is
674 identical to the <code class="directive"><a href="#proxy"><Proxy></a></code> directive, except it matches URLs
675 using <a class="glossarylink" href="../glossary.html#regex" title="see glossary">regular expressions</a>.</p>
679 <li><code class="directive"><a href="#proxy"><Proxy></a></code></li>
682 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
683 <div class="directive-section"><h2><a name="ProxyMaxForwards" id="ProxyMaxForwards">ProxyMaxForwards</a> <a name="proxymaxforwards" id="proxymaxforwards">Directive</a></h2>
684 <table class="directive">
685 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximium number of proxies that a request can be forwarded
687 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyMaxForwards <var>number</var></code></td></tr>
688 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyMaxForwards -1</code></td></tr>
689 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
690 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
691 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
692 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0 and later;
693 default behaviour changed in 2.2.7/2.3</td></tr>
695 <p>The <code class="directive">ProxyMaxForwards</code> directive specifies the
696 maximum number of proxies through which a request may pass, if there's no
697 <code>Max-Forwards</code> header supplied with the request. This may
698 be set to prevent infinite proxy loops, or a DoS attack.</p>
700 <div class="example"><h3>Example</h3><p><code>
704 <p>Note that setting <code class="directive">ProxyMaxForwards</code> is a
705 violation of the HTTP/1.1 protocol (RFC2616), which forbids a Proxy
706 setting <code>Max-Forwards</code> if the Client didn't set it.
707 Earlier Apache versions would always set it. A negative
708 <code class="directive">ProxyMaxForwards</code> value, including the
709 default -1, gives you protocol-compliant behaviour, but may
710 leave you open to loops.</p>
713 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
714 <div class="directive-section"><h2><a name="ProxyPass" id="ProxyPass">ProxyPass</a> <a name="proxypass" id="proxypass">Directive</a></h2>
715 <table class="directive">
716 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maps remote servers into the local server URL-space</td></tr>
717 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPass [<var>path</var>] !|<var>url</var> [<var>key=value</var>
718 <var>[key=value</var> ...]] [nocanon] [interpolate]</code></td></tr>
719 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
720 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
721 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
723 <p>This directive allows remote servers to be mapped into the
724 space of the local server; the local server does not act as a
725 proxy in the conventional sense, but appears to be a mirror of the
726 remote server. The local server is often called a <dfn>reverse
727 proxy</dfn> or <dfn>gateway</dfn>. The <var>path</var> is the name of
728 a local virtual path; <var>url</var> is a partial URL for the
729 remote server and cannot include a query string.</p>
731 <div class="warning">The <code class="directive"><a href="#proxyrequests">ProxyRequests</a></code> directive should
732 usually be set <strong>off</strong> when using
733 <code class="directive">ProxyPass</code>.</div>
735 <p>Suppose the local server has address <code>http://example.com/</code>;
738 <div class="example"><p><code>
739 ProxyPass /mirror/foo/ http://backend.example.com/
742 <p>will cause a local request for
743 <code>http://example.com/mirror/foo/bar</code> to be internally converted
744 into a proxy request to <code>http://backend.example.com/bar</code>.</p>
746 <div class="warning">
747 <p>If the first argument ends with a trailing <strong>/</strong>, the second
748 argument should also end with a trailing <strong>/</strong> and vice
749 versa. Otherwise the resulting requests to the backend may miss some
750 needed slashes and do not deliver the expected results.
754 <p>The <code>!</code> directive is useful in situations where you don't want
755 to reverse-proxy a subdirectory, <em>e.g.</em></p>
757 <div class="example"><p><code>
758 ProxyPass /mirror/foo/i !<br />
759 ProxyPass /mirror/foo http://backend.example.com
762 <p>will proxy all requests to <code>/mirror/foo</code> to
763 <code>backend.example.com</code> <em>except</em> requests made to
764 <code>/mirror/foo/i</code>.</p>
766 <div class="note"><h3>Note</h3>
767 <p>Order is important: exclusions must come <em>before</em> the
768 general <code class="directive">ProxyPass</code> directive.</p>
771 <p>As of Apache 2.1, the ability to use pooled connections to a backend
772 server is available. Using the <code>key=value</code> parameters it is
773 possible to tune this connection pooling. The default for a <code>Hard
774 Maximum</code> for the number of connections is the number of threads per
775 process in the active MPM. In the Prefork MPM, this is always 1, while with
776 the Worker MPM it is controlled by the
777 <code class="directive">ThreadsPerChild</code>.</p>
779 <p>Setting <code>min</code> will determine how many connections will always
780 be open to the backend server. Upto the Soft Maximum or <code>smax</code>
781 number of connections will be created on demand. Any connections above
782 <code>smax</code> are subject to a time to live or <code>ttl</code>. Apache
783 will never create more than the Hard Maximum or <code>max</code> connections
784 to the backend server.</p>
786 <div class="example"><p><code>
787 ProxyPass /example http://backend.example.com smax=5 max=20 ttl=120 retry=300
791 <tr><th>Parameter</th>
793 <th>Description</th></tr>
796 <td>Minimum number of connections that will always
797 be open to the backend server.</td></tr>
800 <td>Hard Maximum number of connections that will be
801 allowed to the backend server. The default for a Hard Maximum
802 for the number of connections is the number of threads per process in the
803 active MPM. In the Prefork MPM, this is always 1, while with the Worker MPM
804 it is controlled by the <code class="directive">ThreadsPerChild</code>.
805 Apache will never create more than the Hard Maximum connections
806 to the backend server.</td></tr>
809 <td>Upto the Soft Maximum
810 number of connections will be created on demand. Any connections above
811 <code>smax</code> are subject to a time to live or <code>ttl</code>.
815 <td>If set this will be the maximum time to wait for a free
816 connection in the connection pool, in milliseconds. If there are no free
817 connections in the pool the Apache will return <code>SERVER_BUSY</code>
818 status to the client.
820 <tr><td>connectiontimeout</td>
822 <td>Connect timeout in seconds.
823 The number of seconds Apache waits for the creation of a connection to
824 the backend to complete. By adding a postfix of ms the timeout can be
825 also set in milliseconds.
827 <tr><td>disablereuse</td>
829 <td>This parameter should be used when you want to force mod_proxy
830 to immediately close a connection to the backend after being used, and
831 thus, disable its persistent connection and pool for that backend.
832 This helps in various situations where a firewall between Apache and
833 the backend server (regardless of protocol) tends to silently
834 drop connections or when backends themselves may be under round-
835 robin DNS. To disable connection pooling reuse,
836 set this property value to <code>On</code>.
838 <tr><td>flushpackets</td>
840 <td>Determines whether the proxy module will auto-flush the output
841 brigade after each "chunk" of data. 'off' means that it will flush
842 only when needed, 'on' means after each chunk is sent and
843 'auto' means poll/wait for a period of time and flush if
844 no input has been received for 'flushwait' milliseconds.
845 Currently this is in effect only for AJP.
847 <tr><td>flushwait</td>
849 <td>The time to wait for additional input, in milliseconds, before
850 flushing the output brigade if 'flushpackets' is 'auto'.
852 <tr><td>iobuffersize</td>
854 <td>Adjusts the size of the internal scratchpad IO buffer. This allows you
855 to override the <code class="directive">ProxyIOBufferSize</code> for a specific worker.
856 This must be at least 512 or set to 0 for the system default of 8192.
858 <tr><td>keepalive</td>
860 <td>This parameter should be used when you have a firewall between your
861 Apache and the backend server, who tend to drop inactive connections.
862 This flag will tell the Operating System to send <code>KEEP_ALIVE</code>
863 messages on inactive connections (interval depends on global OS settings,
864 generally 120ms), and thus prevent the firewall to drop the connection.
865 To enable keepalive set this property value to <code>On</code>.
869 <td>Sets the load balancer cluster set that the worker is a member
870 of. The load balancer will try all members of a lower numbered
871 lbset before trying higher numbered ones.
875 <td>Ping property tells webserver to send a <code>CPING</code>
876 request on ajp13 connection before forwarding a request.
877 The parameter is the delay in seconds to wait for the
878 <code>CPONG</code> reply.
879 This features has been added to avoid problem with hung and
880 busy Tomcat's and require ajp13 ping/pong support which has
881 been implemented on Tomcat 3.3.2+, 4.1.28+ and 5.0.13+.
882 This will increase the network traffic during the normal operation
883 which could be an issue, but it will lower the
884 traffic in case some of the cluster nodes are down or busy.
885 Currently this has an effect only for AJP.
886 By adding a postfix of ms the delay can be also set in
889 <tr><td>receivebuffersize</td>
891 <td>Adjusts the size of the explicit (TCP/IP) network buffer size for
892 proxied connections. This allows you to override the
893 <code class="directive">ProxyReceiveBufferSize</code> for a specific worker.
894 This must be at least 512 or set to 0 for the system default.
896 <tr><td>redirect</td>
898 <td>Redirection Route of the worker. This value is usually
899 set dynamically to enable safe removal of the node from
900 the cluster. If set all requests without session id will be
901 redirected to the BalancerMember that has route parametar
906 <td>Connection pool worker retry timeout in seconds.
907 If the connection pool worker to the backend server is in the error state,
908 Apache will not forward any requests to that server until the timeout
909 expires. This enables to shut down the backend server for maintenance,
910 and bring it back online later. A value of 0 means always retry workers
911 in an error state with no timeout.
915 <td>Route of the worker when used inside load balancer.
916 The route is a value appended to session id.
920 <td>Single letter value defining the initial status of
921 this worker: 'D' is disabled, 'S' is stopped, 'I' is ignore-errors,
922 'H' is hot-standby and 'E' is in an error state. Status
923 can be set (which is the default) by prepending with '+' or
924 cleared by prepending with '-'.
925 Thus, a setting of 'S-E' sets this worker to Stopped and
926 clears the in-error flag.
929 <td><code class="directive"><a href="#proxytimeout">ProxyTimeout</a></code></td>
930 <td>Connection timeout in seconds.
931 The number of seconds Apache waits for data sent by / to the backend.
935 <td>Time To Live for the inactive connections above the
936 <code>smax</code> connections in seconds. Apache will close all
937 connections that has not been used inside that time period.
942 <p>If the Proxy directive scheme starts with the
943 <code>balancer://</code> (eg: <code>balancer://cluster/</code>,
944 any path information is ignored) then a virtual worker that does not really
945 communicate with the backend server will be created. Instead it is responsible
946 for the management of several "real" workers. In that case the special set of
947 parameters can be add to this virtual worker. See <code class="module"><a href="../mod/mod_proxy_balancer.html">mod_proxy_balancer</a></code>
948 for more information about how the balancer works.
951 <tr><th>Parameter</th>
953 <th>Description</th></tr>
954 <tr><td>lbmethod</td>
956 <td>Balancer load-balance method. Select the load-balancing scheduler
957 method to use. Either <code>byrequests</code>, to perform weighted
958 request counting, <code>bytraffic</code>, to perform weighted
959 traffic byte count balancing, or <code>bybusyness</code>, to perform
960 pending request balancing. Default is <code>byrequests</code>.
962 <tr><td>maxattempts</td>
964 <td>Maximum number of failover attempts before giving up.
966 <tr><td>nofailover</td>
968 <td>If set to <code>On</code> the session will break if the worker is in
969 error state or disabled. Set this value to On if backend servers do not
970 support session replication.
972 <tr><td>stickysession</td>
974 <td>Balancer sticky session name. The value is usually set to something
975 like <code>JSESSIONID</code> or <code>PHPSESSIONID</code>,
976 and it depends on the backend application server that support sessions.
977 If the backend application server uses different name for cookies
978 and url encoded id (like servlet containers) use | to to separate them.
979 The first part is for the cookie the second for the path.
981 <tr><td>scolonpathdelim</td>
983 <td>If set to <code>On</code> the semi-colon character ';' will be
984 used as an additional sticky session path deliminator/separator. This
985 is mainly used to emulate mod_jk's behavior when dealing with paths such
986 as <code>JSESSIONID=6736bcf34;foo=aabfa</code>
990 <td>Balancer timeout in seconds. If set this will be the maximum time
991 to wait for a free worker. Default is not to wait.
995 <p>A sample balancer setup</p>
996 <div class="example"><p><code>
997 ProxyPass /special-area http://special.example.com smax=5 max=10<br />
998 ProxyPass / balancer://mycluster/ stickysession=JSESSIONID|jsessionid nofailover=On<br />
999 <Proxy balancer://mycluster><br />
1000 <span class="indent">
1001 BalancerMember http://1.2.3.4:8009<br />
1002 BalancerMember http://1.2.3.5:8009 smax=10<br />
1003 # Less powerful server, don't send as many requests there<br />
1004 BalancerMember http://1.2.3.6:8009 smax=1 loadfactor=20<br />
1009 <p>Setting up a hot-standby, that will only be used if no other
1010 members are available</p>
1011 <div class="example"><p><code>
1012 ProxyPass / balancer://hotcluster/ <br />
1013 <Proxy balancer://hotcluster><br />
1014 <span class="indent">
1015 BalancerMember http://1.2.3.4:8009 loadfactor=1<br />
1016 BalancerMember http://1.2.3.5:8009 loadfactor=2<br />
1017 # The below is the hot standby<br />
1018 BalancerMember http://1.2.3.6:8009 status=+H<br />
1019 ProxySet lbmethod=bytraffic
1024 <p>Normally, mod_proxy will canonicalise ProxyPassed URLs.
1025 But this may be incompatible with some backends, particularly those
1026 that make use of <var>PATH_INFO</var>. The optional <var>nocanon</var>
1027 keyword suppresses this, and passes the URL path "raw" to the
1028 backend. Note that may affect the security of your backend, as it
1029 removes the normal limited protection against URL-based attacks
1030 provided by the proxy.</p>
1032 <p>The optional <var>interpolate</var> keyword (available in
1033 httpd 2.2.9 and later), in combination with
1034 <code class="directive">ProxyPassInterpolateEnv</code> causes the ProxyPass
1035 to interpolate environment variables, using the syntax
1036 <var>${VARNAME}</var>. Note that many of the standard CGI-derived
1037 environment variables will not exist when this interpolation happens,
1038 so you may still have to resort to <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>
1039 for complex rules.</p>
1041 <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
1042 directory is obtained from the <code class="directive"><a href="../mod/core.html#location"><Location></a></code>.</p>
1044 <p>If you require a more flexible reverse-proxy configuration, see the
1045 <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> directive with the
1046 <code>[P]</code> flag.</p>
1049 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1050 <div class="directive-section"><h2><a name="ProxyPassInterpolateEnv" id="ProxyPassInterpolateEnv">ProxyPassInterpolateEnv</a> <a name="proxypassinterpolateenv" id="proxypassinterpolateenv">Directive</a></h2>
1051 <table class="directive">
1052 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enable Environment Variable interpolation in Reverse Proxy configurations</td></tr>
1053 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPassInterpolateEnv On|Off</code></td></tr>
1054 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyPassInterpolateEnv Off</code></td></tr>
1055 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
1056 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1057 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1058 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.2.9 and later</td></tr>
1060 <p>This directive, together with the <var>interpolate</var> argument to
1061 <code class="directive">ProxyPass</code>, <code class="directive">ProxyPassReverse</code>,
1062 <code class="directive">ProxyPassReverseCookieDomain</code> and
1063 <code class="directive">ProxyPassReverseCookiePath</code>
1064 enables reverse proxies to be dynamically
1065 configured using environment variables, which may be set by
1066 another module such as <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>.
1067 It affects the <code class="directive">ProxyPass</code>,
1068 <code class="directive">ProxyPassReverse</code>,
1069 <code class="directive">ProxyPassReverseCookieDomain</code>, and
1070 <code class="directive">ProxyPassReverseCookiePath</code> directives,
1071 and causes them to substitute the value of an environment
1072 variable <code>varname</code> for the string <code>${varname}</code>
1073 in configuration directives.</p>
1074 <p>Keep this turned off (for server performance) unless you need it!</p>
1077 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1078 <div class="directive-section"><h2><a name="ProxyPassMatch" id="ProxyPassMatch">ProxyPassMatch</a> <a name="proxypassmatch" id="proxypassmatch">Directive</a></h2>
1079 <table class="directive">
1080 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maps remote servers into the local server URL-space using regular expressions</td></tr>
1081 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPassMatch [<var>regex</var>] !|<var>url</var> [<var>key=value</var>
1082 <var>[key=value</var> ...]]</code></td></tr>
1083 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
1084 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1085 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1087 <p>This directive is equivalent to <code class="directive"><a href="#proxypass">ProxyPass</a></code>,
1088 but makes use of regular expressions, instead of simple prefix matching. The
1089 supplied regular expression is matched against the <var>url</var>, and if it
1090 matches, the server will substitute any parenthesized matches into the given
1091 string and use it as a new <var>url</var>.</p>
1093 <p>Suppose the local server has address <code>http://example.com/</code>;
1096 <div class="example"><p><code>
1097 ProxyPassMatch ^(/.*\.gif)$ http://backend.example.com$1
1100 <p>will cause a local request for
1101 <code>http://example.com/foo/bar.gif</code> to be internally converted
1102 into a proxy request to <code>http://backend.example.com/foo/bar.gif</code>.</p>
1103 <div class="note"><h3>Note</h3>
1104 <p>The URL argument must be parsable as a URL <em>before</em> regexp
1105 substitutions (as well as after). This limits the matches you can use.
1106 For instance, if we had used</p>
1107 <div class="example"><p><code>
1108 ProxyPassMatch ^(/.*\.gif)$ http://backend.example.com:8000$1
1110 <p>in our previous example, it would fail with a syntax error
1111 at server startup. This is a bug (PR 46665 in the ASF bugzilla),
1112 and the workaround is to reformulate the match:</p>
1113 <div class="example"><p><code>
1114 ProxyPassMatch ^/(.*\.gif)$ http://backend.example.com:8000/$1
1117 <p>The <code>!</code> directive is useful in situations where you don't want
1118 to reverse-proxy a subdirectory.</p>
1121 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1122 <div class="directive-section"><h2><a name="ProxyPassReverse" id="ProxyPassReverse">ProxyPassReverse</a> <a name="proxypassreverse" id="proxypassreverse">Directive</a></h2>
1123 <table class="directive">
1124 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Adjusts the URL in HTTP response headers sent from a reverse
1125 proxied server</td></tr>
1126 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPassReverse [<var>path</var>] <var>url</var>
1127 [<var>interpolate</var>]</code></td></tr>
1128 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
1129 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1130 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1132 <p>This directive lets Apache adjust the URL in the <code>Location</code>,
1133 <code>Content-Location</code> and <code>URI</code> headers on HTTP
1134 redirect responses. This is essential when Apache is used as a
1135 reverse proxy (or gateway) to avoid by-passing the reverse proxy
1136 because of HTTP redirects on the backend servers which stay behind
1137 the reverse proxy.</p>
1139 <p>Only the HTTP response headers specifically mentioned above
1140 will be rewritten. Apache will not rewrite other response
1141 headers, nor will it rewrite URL references inside HTML pages.
1142 This means that if the proxied content contains absolute URL
1143 references, they will by-pass the proxy. A third-party module
1144 that will look inside the HTML and rewrite URL references is Nick
1145 Kew's <a href="http://apache.webthing.com/mod_proxy_html/">mod_proxy_html</a>.</p>
1147 <p><var>path</var> is the name of a local virtual path. <var>url</var> is a
1148 partial URL for the remote server - the same way they are used for the
1149 <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.</p>
1151 <p>For example, suppose the local server has address
1152 <code>http://example.com/</code>; then</p>
1154 <div class="example"><p><code>
1155 ProxyPass /mirror/foo/ http://backend.example.com/<br />
1156 ProxyPassReverse /mirror/foo/ http://backend.example.com/<br />
1157 ProxyPassReverseCookieDomain backend.example.com public.example.com<br />
1158 ProxyPassReverseCookiePath / /mirror/foo/
1161 <p>will not only cause a local request for the
1162 <code>http://example.com/mirror/foo/bar</code> to be internally converted
1163 into a proxy request to <code>http://backend.example.com/bar</code>
1164 (the functionality <code>ProxyPass</code> provides here). It also takes care
1165 of redirects the server <code>backend.example.com</code> sends: when
1166 <code>http://backend.example.com/bar</code> is redirected by him to
1167 <code>http://backend.example.com/quux</code> Apache adjusts this to
1168 <code>http://example.com/mirror/foo/quux</code> before forwarding the HTTP
1169 redirect response to the client. Note that the hostname used for
1170 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>
1172 <p>Note that this <code class="directive">ProxyPassReverse</code> directive can
1173 also be used in conjunction with the proxy pass-through feature
1174 (<code>RewriteRule ... [P]</code>) from <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>
1175 because it doesn't depend on a corresponding <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.</p>
1177 <p>The optional <var>interpolate</var> keyword (available in
1178 httpd 2.2.9 and later), used together with
1179 <code class="directive">ProxyPassInterpolateEnv</code>, enables interpolation
1180 of environment variables specified using the format <var>${VARNAME}</var>.
1183 <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
1184 directory is obtained from the <code class="directive"><a href="../mod/core.html#location"><Location></a></code>.</p>
1187 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1188 <div class="directive-section"><h2><a name="ProxyPassReverseCookieDomain" id="ProxyPassReverseCookieDomain">ProxyPassReverseCookieDomain</a> <a name="proxypassreversecookiedomain" id="proxypassreversecookiedomain">Directive</a></h2>
1189 <table class="directive">
1190 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Adjusts the Domain string in Set-Cookie headers from a reverse-
1191 proxied server</td></tr>
1192 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPassReverseCookieDomain <var>internal-domain</var>
1193 <var>public-domain</var> [<var>interpolate</var>]</code></td></tr>
1194 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
1195 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1196 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1198 <p>Usage is basically similar to
1199 <code class="directive"><a href="#proxypassreverse">ProxyPassReverse</a></code>, but instead of
1200 rewriting headers that are a URL, this rewrites the <code>domain</code>
1201 string in <code>Set-Cookie</code> headers.</p>
1204 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1205 <div class="directive-section"><h2><a name="ProxyPassReverseCookiePath" id="ProxyPassReverseCookiePath">ProxyPassReverseCookiePath</a> <a name="proxypassreversecookiepath" id="proxypassreversecookiepath">Directive</a></h2>
1206 <table class="directive">
1207 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Adjusts the Path string in Set-Cookie headers from a reverse-
1208 proxied server</td></tr>
1209 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPassReverseCookiePath <var>internal-path</var>
1210 <var>public-path</var> [<var>interpolate</var>]</code></td></tr>
1211 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
1212 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1213 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1215 <p>Usage is basically similar to
1216 <code class="directive"><a href="#proxypassreverse">ProxyPassReverse</a></code>, but instead of
1217 rewriting headers that are a URL, this rewrites the <code>path</code>
1218 string in <code>Set-Cookie</code> headers.</p>
1221 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1222 <div class="directive-section"><h2><a name="ProxyPreserveHost" id="ProxyPreserveHost">ProxyPreserveHost</a> <a name="proxypreservehost" id="proxypreservehost">Directive</a></h2>
1223 <table class="directive">
1224 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Use incoming Host HTTP request header for proxy
1226 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyPreserveHost On|Off</code></td></tr>
1227 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyPreserveHost Off</code></td></tr>
1228 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory</td></tr>
1229 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1230 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1231 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.31 and later.</td></tr>
1233 <p>When enabled, this option will pass the Host: line from the incoming
1234 request to the proxied host, instead of the hostname specified in the
1235 <code class="directive">ProxyPass</code> line.</p>
1237 <p>This option should normally be turned <code>Off</code>. It is mostly
1238 useful in special configurations like proxied mass name-based virtual
1239 hosting, where the original Host header needs to be evaluated by the
1243 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1244 <div class="directive-section"><h2><a name="ProxyReceiveBufferSize" id="ProxyReceiveBufferSize">ProxyReceiveBufferSize</a> <a name="proxyreceivebuffersize" id="proxyreceivebuffersize">Directive</a></h2>
1245 <table class="directive">
1246 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Network buffer size for proxied HTTP and FTP
1247 connections</td></tr>
1248 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyReceiveBufferSize <var>bytes</var></code></td></tr>
1249 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyReceiveBufferSize 0</code></td></tr>
1250 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1251 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1252 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1254 <p>The <code class="directive">ProxyReceiveBufferSize</code> directive specifies an
1255 explicit (TCP/IP) network buffer size for proxied HTTP and FTP connections,
1256 for increased throughput. It has to be greater than <code>512</code> or set
1257 to <code>0</code> to indicate that the system's default buffer size should
1260 <div class="example"><h3>Example</h3><p><code>
1261 ProxyReceiveBufferSize 2048
1265 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1266 <div class="directive-section"><h2><a name="ProxyRemote" id="ProxyRemote">ProxyRemote</a> <a name="proxyremote" id="proxyremote">Directive</a></h2>
1267 <table class="directive">
1268 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Remote proxy used to handle certain requests</td></tr>
1269 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRemote <var>match</var> <var>remote-server</var></code></td></tr>
1270 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1271 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1272 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1274 <p>This defines remote proxies to this proxy. <var>match</var> is either the
1275 name of a URL-scheme that the remote server supports, or a partial URL
1276 for which the remote server should be used, or <code>*</code> to indicate
1277 the server should be contacted for all requests. <var>remote-server</var> is
1278 a partial URL for the remote server. Syntax:</p>
1280 <div class="example"><p><code>
1281 <dfn>remote-server</dfn> =
1282 <var>scheme</var>://<var>hostname</var>[:<var>port</var>]
1285 <p><var>scheme</var> is effectively the protocol that should be used to
1286 communicate with the remote server; only <code>http</code> and <code>https</code>
1287 are supported by this module. When using <code>https</code>, the requests
1288 are forwarded through the remote proxy using the HTTP CONNECT method.</p>
1290 <div class="example"><h3>Example</h3><p><code>
1291 ProxyRemote http://goodguys.example.com/ http://mirrorguys.example.com:8000<br />
1292 ProxyRemote * http://cleverproxy.localdomain<br />
1293 ProxyRemote ftp http://ftpproxy.mydomain:8080
1296 <p>In the last example, the proxy will forward FTP requests, encapsulated
1297 as yet another HTTP proxy request, to another proxy which can handle
1300 <p>This option also supports reverse proxy configuration - a backend
1301 webserver can be embedded within a virtualhost URL space even if that
1302 server is hidden by another forward proxy.</p>
1305 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1306 <div class="directive-section"><h2><a name="ProxyRemoteMatch" id="ProxyRemoteMatch">ProxyRemoteMatch</a> <a name="proxyremotematch" id="proxyremotematch">Directive</a></h2>
1307 <table class="directive">
1308 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Remote proxy used to handle requests matched by regular
1309 expressions</td></tr>
1310 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRemoteMatch <var>regex</var> <var>remote-server</var></code></td></tr>
1311 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1312 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1313 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1315 <p>The <code class="directive">ProxyRemoteMatch</code> is identical to the
1316 <code class="directive"><a href="#proxyremote">ProxyRemote</a></code> directive, except the
1317 first argument is a <a class="glossarylink" href="../glossary.html#regex" title="see glossary">regular expression</a>
1318 match against the requested URL.</p>
1321 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1322 <div class="directive-section"><h2><a name="ProxyRequests" id="ProxyRequests">ProxyRequests</a> <a name="proxyrequests" id="proxyrequests">Directive</a></h2>
1323 <table class="directive">
1324 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables forward (standard) proxy requests</td></tr>
1325 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyRequests On|Off</code></td></tr>
1326 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyRequests Off</code></td></tr>
1327 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1328 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1329 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1331 <p>This allows or prevents Apache from functioning as a forward proxy
1332 server. (Setting ProxyRequests to <code>Off</code> does not disable use of
1333 the <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.)</p>
1335 <p>In a typical reverse proxy or gateway configuration, this
1336 option should be set to
1337 <code>Off</code>.</p>
1339 <p>In order to get the functionality of proxying HTTP or FTP sites, you
1340 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>
1341 (or both) present in the server.</p>
1343 <div class="warning"><h3>Warning</h3>
1344 <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
1345 both to your network and to the Internet at large.</p>
1350 <li><a href="#forwardreverse">Forward and Reverse Proxies/Gateways</a></li>
1353 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1354 <div class="directive-section"><h2><a name="ProxySet" id="ProxySet">ProxySet</a> <a name="proxyset" id="proxyset">Directive</a></h2>
1355 <table class="directive">
1356 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Set various Proxy balancer or member parameters</td></tr>
1357 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxySet <var>url</var> <var>key=value [key=value ...]</var></code></td></tr>
1358 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory</td></tr>
1359 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1360 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1361 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>ProxySet is only available in Apache 2.2
1362 and later.</td></tr>
1364 <p>This directive is used as an alternate method of setting any of the
1365 parameters available to Proxy balancers and workers normally done via the
1366 <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive. If used
1367 within a <code><Proxy <var>balancer url|worker url</var>></code>
1368 container directive, the <var>url</var> argument is not required. As a side
1369 effect the respective balancer or worker gets created. This can be useful
1370 when doing reverse proxying via a
1371 <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> instead of a
1372 <code class="directive"><a href="#proxypass">ProxyPass</a></code> directive.</p>
1374 <div class="example"><p><code>
1375 <Proxy balancer://hotcluster><br />
1376 <span class="indent">
1377 BalancerMember http://www2.example.com:8009 loadfactor=1<br />
1378 BalancerMember http://www3.example.com:8009 loadfactor=2<br />
1379 ProxySet lbmethod=bytraffic<br />
1384 <div class="example"><p><code>
1385 <Proxy http://backend><br />
1386 <span class="indent">
1387 ProxySet keepalive=On<br />
1392 <div class="example"><p><code>
1393 ProxySet balancer://foo lbmethod=bytraffic timeout=15
1396 <div class="example"><p><code>
1397 ProxySet ajp://backend:7001 timeout=15
1400 <div class="warning"><h3>Warning</h3>
1401 <p>Keep in mind that the same parameter key can have a different meaning
1402 depending whether it is applied to a balancer or a worker as shown by the two
1403 examples above regarding timeout.</p>
1408 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1409 <div class="directive-section"><h2><a name="ProxyStatus" id="ProxyStatus">ProxyStatus</a> <a name="proxystatus" id="proxystatus">Directive</a></h2>
1410 <table class="directive">
1411 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Show Proxy LoadBalancer status in mod_status</td></tr>
1412 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyStatus Off|On|Full</code></td></tr>
1413 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyStatus Off</code></td></tr>
1414 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1415 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1416 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1417 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in version 2.2 and later</td></tr>
1419 <p>This directive determines whether or not proxy
1420 loadbalancer status data is displayed via the <code class="module"><a href="../mod/mod_status.html">mod_status</a></code>
1421 server-status page.</p>
1422 <div class="note"><h3>Note</h3>
1423 <p><strong>Full</strong> is synonymous with <strong>On</strong></p>
1428 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1429 <div class="directive-section"><h2><a name="ProxyTimeout" id="ProxyTimeout">ProxyTimeout</a> <a name="proxytimeout" id="proxytimeout">Directive</a></h2>
1430 <table class="directive">
1431 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Network timeout for proxied requests</td></tr>
1432 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyTimeout <var>seconds</var></code></td></tr>
1433 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Value of <code class="directive"><a href="../mod/core.html#timeout">Timeout</a></code></code></td></tr>
1434 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1435 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1436 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1437 <tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.31 and later</td></tr>
1439 <p>This directive allows a user to specifiy a timeout on proxy requests.
1440 This is useful when you have a slow/buggy appserver which hangs, and you
1441 would rather just return a timeout and fail gracefully instead of waiting
1442 however long it takes the server to return.</p>
1445 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
1446 <div class="directive-section"><h2><a name="ProxyVia" id="ProxyVia">ProxyVia</a> <a name="proxyvia" id="proxyvia">Directive</a></h2>
1447 <table class="directive">
1448 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Information provided in the <code>Via</code> HTTP response
1449 header for proxied requests</td></tr>
1450 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ProxyVia On|Off|Full|Block</code></td></tr>
1451 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ProxyVia Off</code></td></tr>
1452 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
1453 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
1454 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_proxy</td></tr>
1456 <p>This directive controls the use of the <code>Via:</code> HTTP
1457 header by the proxy. Its intended use is to control the flow of
1458 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
1459 14.45 for an explanation of <code>Via:</code> header lines.</p>
1462 <li>If set to <code>Off</code>, which is the default, no special processing
1463 is performed. If a request or reply contains a <code>Via:</code> header,
1464 it is passed through unchanged.</li>
1466 <li>If set to <code>On</code>, each request and reply will get a
1467 <code>Via:</code> header line added for the current host.</li>
1469 <li>If set to <code>Full</code>, each generated <code>Via:</code> header
1470 line will additionally have the Apache server version shown as a
1471 <code>Via:</code> comment field.</li>
1473 <li>If set to <code>Block</code>, every proxy request will have all its
1474 <code>Via:</code> header lines removed. No new <code>Via:</code> header will
1480 <div class="bottomlang">
1481 <p><span>Available Languages: </span><a href="../en/mod/mod_proxy.html" title="English"> en </a> |
1482 <a href="../fr/mod/mod_proxy.html" hreflang="fr" rel="alternate" title="Français"> fr </a> |
1483 <a href="../ja/mod/mod_proxy.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a></p>
1484 </div><div id="footer">
1485 <p class="apache">Copyright 2010 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>
1486 <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>