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16 <p class="apache">Apache HTTP Server Version 2.3</p>
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20 <a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs/">Documentation</a> > <a href="../">Version 2.3</a> > <a href="./">Modules</a></div>
21 <div id="page-content">
22 <div id="preamble"><h1>Apache Module mod_cache</h1>
24 <p><span>Available Languages: </span><a href="../en/mod/mod_cache.html" title="English"> en </a> |
25 <a href="../ja/mod/mod_cache.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> |
26 <a href="../ko/mod/mod_cache.html" hreflang="ko" rel="alternate" title="Korean"> ko </a></p>
28 <table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Content cache keyed to URIs.</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>cache_module</td></tr>
31 <tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>mod_cache.c</td></tr></table>
34 <div class="warning">This module should be used with care and
35 can be used to circumvent <code class="directive"><a href="../mod/mod_authz_host.html#allow">Allow</a></code> and <code class="directive"><a href="../mod/mod_authz_host.html#deny">Deny</a></code> directives. You
36 should not enable caching for any content to which you wish
37 to limit access by client host name, address or environment
40 <p><code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code> implements an <a href="http://www.ietf.org/rfc/rfc2616.txt">RFC 2616</a> compliant HTTP
41 content cache that can be used to cache either local or proxied content.
42 <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code> requires the services of one or more storage
43 management modules. Two storage management modules are included in
44 the base Apache distribution:</p>
46 <dt><code class="module"><a href="../mod/mod_disk_cache.html">mod_disk_cache</a></code></dt>
47 <dd>implements a disk based storage manager.</dd>
49 <dt><code class="module"><a href="../mod/mod_mem_cache.html">mod_mem_cache</a></code></dt>
50 <dd>implements a memory based storage manager.
51 <code class="module"><a href="../mod/mod_mem_cache.html">mod_mem_cache</a></code> can be configured to operate in two
52 modes: caching open file descriptors or caching objects in heap storage.
53 <code class="module"><a href="../mod/mod_mem_cache.html">mod_mem_cache</a></code> can be used to cache locally generated content
54 or to cache backend server content for <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code> when
55 configured using <code class="directive"><a href="../mod/mod_proxy.html#proxypass">ProxyPass</a></code>
56 (aka <dfn>reverse proxy</dfn>)</dd>
59 <p>Content is stored in and retrieved from the cache using URI based keys. Content with
60 access protection is not cached.</p>
61 <p>Further details, discussion, and examples, are provided in the
62 <a href="../caching.html">Caching Guide</a>.</p>
64 <div id="quickview"><h3 class="directives">Directives</h3>
66 <li><img alt="" src="../images/down.gif" /> <a href="#cachedefaultexpire">CacheDefaultExpire</a></li>
67 <li><img alt="" src="../images/down.gif" /> <a href="#cachedisable">CacheDisable</a></li>
68 <li><img alt="" src="../images/down.gif" /> <a href="#cacheenable">CacheEnable</a></li>
69 <li><img alt="" src="../images/down.gif" /> <a href="#cacheignorecachecontrol">CacheIgnoreCacheControl</a></li>
70 <li><img alt="" src="../images/down.gif" /> <a href="#cacheignoreheaders">CacheIgnoreHeaders</a></li>
71 <li><img alt="" src="../images/down.gif" /> <a href="#cacheignorenolastmod">CacheIgnoreNoLastMod</a></li>
72 <li><img alt="" src="../images/down.gif" /> <a href="#cacheignorequerystring">CacheIgnoreQueryString</a></li>
73 <li><img alt="" src="../images/down.gif" /> <a href="#cachelastmodifiedfactor">CacheLastModifiedFactor</a></li>
74 <li><img alt="" src="../images/down.gif" /> <a href="#cachemaxexpire">CacheMaxExpire</a></li>
75 <li><img alt="" src="../images/down.gif" /> <a href="#cacheminexpire">CacheMinExpire</a></li>
76 <li><img alt="" src="../images/down.gif" /> <a href="#cachestorenostore">CacheStoreNoStore</a></li>
77 <li><img alt="" src="../images/down.gif" /> <a href="#cachestoreprivate">CacheStorePrivate</a></li>
81 <li><img alt="" src="../images/down.gif" /> <a href="#related">Related Modules and Directives</a></li>
82 <li><img alt="" src="../images/down.gif" /> <a href="#sampleconf">Sample Configuration</a></li>
83 </ul><h3>See also</h3>
85 <li><a href="../caching.html">Caching Guide</a></li>
87 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
89 <h2><a name="related" id="related">Related Modules and Directives</a></h2>
90 <table class="related"><tr><th>Related Modules</th><th>Related Directives</th></tr><tr><td><ul><li><code class="module"><a href="../mod/mod_disk_cache.html">mod_disk_cache</a></code></li><li><code class="module"><a href="../mod/mod_mem_cache.html">mod_mem_cache</a></code></li></ul></td><td><ul><li><code class="directive"><a href="../mod/mod_disk_cache.html#cacheroot">CacheRoot</a></code></li><li><code class="directive"><a href="../mod/mod_disk_cache.html#cachedirlevels">CacheDirLevels</a></code></li><li><code class="directive"><a href="../mod/mod_disk_cache.html#cachedirlength">CacheDirLength</a></code></li><li><code class="directive"><a href="../mod/mod_disk_cache.html#cacheminfilesize">CacheMinFileSize</a></code></li><li><code class="directive"><a href="../mod/mod_disk_cache.html#cachemaxfilesize">CacheMaxFileSize</a></code></li><li><code class="directive"><a href="../mod/mod_mem_cache.html#mcachesize">MCacheSize</a></code></li><li><code class="directive"><a href="../mod/mod_mem_cache.html#mcachemaxobjectcount">MCacheMaxObjectCount</a></code></li><li><code class="directive"><a href="../mod/mod_mem_cache.html#mcacheminobjectsize">MCacheMinObjectSize</a></code></li><li><code class="directive"><a href="../mod/mod_mem_cache.html#mcachemaxobjectsize">MCacheMaxObjectSize</a></code></li><li><code class="directive"><a href="../mod/mod_mem_cache.html#mcacheremovalalgorithm">MCacheRemovalAlgorithm</a></code></li><li><code class="directive"><a href="../mod/mod_mem_cache.html#mcachemaxstreamingbuffer">MCacheMaxStreamingBuffer</a></code></li></ul></td></tr></table>
91 </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
93 <h2><a name="sampleconf" id="sampleconf">Sample Configuration</a></h2>
94 <div class="example"><h3>Sample httpd.conf</h3><p><code>
96 # Sample Cache Configuration<br />
98 LoadModule cache_module modules/mod_cache.so<br />
100 <IfModule mod_cache.c><br />
101 <span class="indent">
102 #LoadModule disk_cache_module modules/mod_disk_cache.so<br />
103 # If you want to use mod_disk_cache instead of mod_mem_cache,<br />
104 # uncomment the line above and comment out the LoadModule line below.<br />
105 <IfModule mod_disk_cache.c><br />
106 <span class="indent">
107 CacheRoot c:/cacheroot<br />
108 CacheEnable disk /<br />
109 CacheDirLevels 5<br />
110 CacheDirLength 3<br />
112 </IfModule> <br />
114 LoadModule mem_cache_module modules/mod_mem_cache.so<br />
115 <IfModule mod_mem_cache.c><br />
116 <span class="indent">
117 CacheEnable mem /<br />
118 MCacheSize 4096<br />
119 MCacheMaxObjectCount 100<br />
120 MCacheMinObjectSize 1<br />
121 MCacheMaxObjectSize 2048<br />
123 </IfModule><br />
125 # When acting as a proxy, don't cache the list of security updates<br />
126 CacheDisable http://security.update.server/update-list/<br />
131 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
132 <div class="directive-section"><h2><a name="CacheDefaultExpire" id="CacheDefaultExpire">CacheDefaultExpire</a> <a name="cachedefaultexpire" id="cachedefaultexpire">Directive</a></h2>
133 <table class="directive">
134 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>The default duration to cache a document when no expiry date is specified.</td></tr>
135 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheDefaultExpire <var>seconds</var></code></td></tr>
136 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheDefaultExpire 3600 (one hour)</code></td></tr>
137 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
138 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
139 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache</td></tr>
141 <p>The <code class="directive">CacheDefaultExpire</code> directive specifies a default time,
142 in seconds, to cache a document if neither an expiry date nor last-modified date are provided
143 with the document. The value specified with the <code class="directive">CacheMaxExpire</code>
144 directive does <em>not</em> override this setting.</p>
146 <div class="example"><p><code>
147 CacheDefaultExpire 86400
151 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
152 <div class="directive-section"><h2><a name="CacheDisable" id="CacheDisable">CacheDisable</a> <a name="cachedisable" id="cachedisable">Directive</a></h2>
153 <table class="directive">
154 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Disable caching of specified URLs</td></tr>
155 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheDisable <var> url-string</var></code></td></tr>
156 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
157 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
158 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache</td></tr>
160 <p>The <code class="directive">CacheDisable</code> directive instructs
161 <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code> to <em>not</em> cache urls at or below
162 <var>url-string</var>.</p>
164 <div class="example"><h3>Example</h3><p><code>
165 CacheDisable /local_files
169 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
170 <div class="directive-section"><h2><a name="CacheEnable" id="CacheEnable">CacheEnable</a> <a name="cacheenable" id="cacheenable">Directive</a></h2>
171 <table class="directive">
172 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enable caching of specified URLs using a specified storage
174 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheEnable <var>cache_type</var> <var>url-string</var></code></td></tr>
175 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
176 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
177 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache</td></tr>
179 <p>The <code class="directive">CacheEnable</code> directive instructs
180 <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code> to cache urls at or below
181 <var>url-string</var>. The cache storage manager is specified with the
182 <var>cache_type</var> argument. <var>cache_type</var> <code> mem</code>
183 instructs <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code> to use the memory based storage
184 manager implemented by <code class="module"><a href="../mod/mod_mem_cache.html">mod_mem_cache</a></code>.
185 <var>cache_type</var> <code>disk</code> instructs
186 <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code> to use the disk based storage manager
187 implemented by <code class="module"><a href="../mod/mod_disk_cache.html">mod_disk_cache</a></code>.
188 <var>cache_type</var> <code>fd</code> instructs
189 <code class="module"><a href="../mod/mod_cache.html">mod_cache</a></code> to use the file descriptor cache implemented
190 by <code class="module"><a href="../mod/mod_mem_cache.html">mod_mem_cache</a></code>.</p>
191 <p>In the event that the URL space overlaps between different
192 <code class="directive">CacheEnable</code> directives (as in the example below),
193 each possible storage manager will be run until the first one that
194 actually processes the request. The order in which the storage managers are
195 run is determined by the order of the <code class="directive">CacheEnable</code>
196 directives in the configuration file.</p>
198 <div class="example"><p><code>
199 CacheEnable mem /manual<br />
200 CacheEnable fd /images<br />
201 CacheEnable disk /<br />
204 <p>When acting as a forward proxy server, <var>url-string</var> can
205 also be used to specify remote sites and proxy protocols which
206 caching should be enabled for.</p>
208 <div class="example"><p><code>
209 # Cache proxied url's<br />
210 CacheEnable disk /<br /><br />
211 # Cache FTP-proxied url's<br />
212 CacheEnable disk ftp://<br /><br />
213 # Cache content from www.apache.org<br />
214 CacheEnable disk http://www.apache.org/<br />
219 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
220 <div class="directive-section"><h2><a name="CacheIgnoreCacheControl" id="CacheIgnoreCacheControl">CacheIgnoreCacheControl</a> <a name="cacheignorecachecontrol" id="cacheignorecachecontrol">Directive</a></h2>
221 <table class="directive">
222 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Ignore request to not serve cached content to client</td></tr>
223 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheIgnoreCacheControl On|Off</code></td></tr>
224 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheIgnoreCacheControl Off</code></td></tr>
225 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
226 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
227 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache</td></tr>
229 <p>Ordinarily, requests containing a Cache-Control: no-cache or
230 Pragma: no-cache header value will not be served from the cache. The
231 <code class="directive">CacheIgnoreCacheControl</code> directive allows this
232 behavior to be overridden. <code class="directive">CacheIgnoreCacheControl</code>
233 On tells the server to attempt to serve the resource from the cache even
234 if the request contains no-cache header values. Resources requiring
235 authorization will <em>never</em> be cached.</p>
237 <div class="example"><p><code>
238 CacheIgnoreCacheControl On
241 <div class="warning"><h3>Warning:</h3>
242 This directive will allow serving from the cache even if the client has
243 requested that the document not be served from the cache. This might
244 result in stale content being served.
249 <li><code class="directive"><a href="#cachestoreprivate">CacheStorePrivate</a></code></li>
250 <li><code class="directive"><a href="#cachestorenostore">CacheStoreNoStore</a></code></li>
253 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
254 <div class="directive-section"><h2><a name="CacheIgnoreHeaders" id="CacheIgnoreHeaders">CacheIgnoreHeaders</a> <a name="cacheignoreheaders" id="cacheignoreheaders">Directive</a></h2>
255 <table class="directive">
256 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Do not store the given HTTP header(s) in the cache.
258 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheIgnoreHeaders <var>header-string</var> [<var>header-string</var>] ...</code></td></tr>
259 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheIgnoreHeaders None</code></td></tr>
260 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
261 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
262 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache</td></tr>
264 <p>According to RFC 2616, hop-by-hop HTTP headers are not stored in
265 the cache. The following HTTP headers are hop-by-hop headers and thus
266 do not get stored in the cache in <em>any</em> case regardless of the
267 setting of <code class="directive">CacheIgnoreHeaders</code>:</p>
270 <li><code>Connection</code></li>
271 <li><code>Keep-Alive</code></li>
272 <li><code>Proxy-Authenticate</code></li>
273 <li><code>Proxy-Authorization</code></li>
274 <li><code>TE</code></li>
275 <li><code>Trailers</code></li>
276 <li><code>Transfer-Encoding</code></li>
277 <li><code>Upgrade</code></li>
280 <p><code class="directive">CacheIgnoreHeaders</code> specifies additional HTTP
281 headers that should not to be stored in the cache. For example, it makes
282 sense in some cases to prevent cookies from being stored in the cache.</p>
284 <p><code class="directive">CacheIgnoreHeaders</code> takes a space separated list
285 of HTTP headers that should not be stored in the cache. If only hop-by-hop
286 headers not should be stored in the cache (the RFC 2616 compliant
287 behaviour), <code class="directive">CacheIgnoreHeaders</code> can be set to
288 <code>None</code>.</p>
290 <div class="example"><h3>Example 1</h3><p><code>
291 CacheIgnoreHeaders Set-Cookie
294 <div class="example"><h3>Example 2</h3><p><code>
295 CacheIgnoreHeaders None
298 <div class="warning"><h3>Warning:</h3>
299 If headers like <code>Expires</code> which are needed for proper cache
300 management are not stored due to a
301 <code class="directive">CacheIgnoreHeaders</code> setting, the behaviour of
302 mod_cache is undefined.
306 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
307 <div class="directive-section"><h2><a name="CacheIgnoreNoLastMod" id="CacheIgnoreNoLastMod">CacheIgnoreNoLastMod</a> <a name="cacheignorenolastmod" id="cacheignorenolastmod">Directive</a></h2>
308 <table class="directive">
309 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Ignore the fact that a response has no Last Modified
311 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheIgnoreNoLastMod On|Off</code></td></tr>
312 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheIgnoreNoLastMod Off</code></td></tr>
313 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
314 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
315 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache</td></tr>
317 <p>Ordinarily, documents without a last-modified date are not cached.
318 Under some circumstances the last-modified date is removed (during
319 <code class="module"><a href="../mod/mod_include.html">mod_include</a></code> processing for example) or not provided
320 at all. The <code class="directive">CacheIgnoreNoLastMod</code> directive
321 provides a way to specify that documents without last-modified dates
322 should be considered for caching, even without a last-modified date.
323 If neither a last-modified date nor an expiry date are provided with
324 the document then the value specified by the
325 <code class="directive">CacheDefaultExpire</code> directive will be used to
326 generate an expiration date.</p>
328 <div class="example"><p><code>
329 CacheIgnoreNoLastMod On
333 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
334 <div class="directive-section"><h2><a name="CacheIgnoreQueryString" id="CacheIgnoreQueryString">CacheIgnoreQueryString</a> <a name="cacheignorequerystring" id="cacheignorequerystring">Directive</a></h2>
335 <table class="directive">
336 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Ignore query string when caching</td></tr>
337 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheIgnoreQueryString On|Off</code></td></tr>
338 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheIgnoreQueryString Off</code></td></tr>
339 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
340 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
341 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache</td></tr>
343 <p>Ordinarily, requests with query string parameters are cached separately
344 for each unique query string. This is according to RFC 2616/13.9 done only
345 if an expiration time is specified. The
346 <code class="directive">CacheIgnoreQueryString</code> directive tells the cache to
347 cache requests even if no expiration time is specified, and to reply with
348 a cached reply even if the query string differs. From a caching point of
349 view the request is treated as if having no query string when this
350 directive is enabled.</p>
352 <div class="example"><p><code>
353 CacheIgnoreQueryString On
358 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
359 <div class="directive-section"><h2><a name="CacheLastModifiedFactor" id="CacheLastModifiedFactor">CacheLastModifiedFactor</a> <a name="cachelastmodifiedfactor" id="cachelastmodifiedfactor">Directive</a></h2>
360 <table class="directive">
361 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>The factor used to compute an expiry date based on the
362 LastModified date.</td></tr>
363 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheLastModifiedFactor <var>float</var></code></td></tr>
364 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheLastModifiedFactor 0.1</code></td></tr>
365 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
366 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
367 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache</td></tr>
369 <p>In the event that a document does not provide an expiry date but does
370 provide a last-modified date, an expiry date can be calculated based on
371 the time since the document was last modified. The
372 <code class="directive">CacheLastModifiedFactor</code> directive specifies a
373 <var>factor</var> to be used in the generation of this expiry date
374 according to the following formula:
376 <code>expiry-period = time-since-last-modified-date * <var>factor</var>
377 expiry-date = current-date + expiry-period</code>
379 For example, if the document was last modified 10 hours ago, and
380 <var>factor</var> is 0.1 then the expiry-period will be set to
381 10*0.1 = 1 hour. If the current time was 3:00pm then the computed
382 expiry-date would be 3:00pm + 1hour = 4:00pm.
384 If the expiry-period would be longer than that set by
385 <code class="directive">CacheMaxExpire</code>, then the latter takes
388 <div class="example"><p><code>
389 CacheLastModifiedFactor 0.5
393 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
394 <div class="directive-section"><h2><a name="CacheMaxExpire" id="CacheMaxExpire">CacheMaxExpire</a> <a name="cachemaxexpire" id="cachemaxexpire">Directive</a></h2>
395 <table class="directive">
396 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>The maximum time in seconds to cache a document</td></tr>
397 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheMaxExpire <var>seconds</var></code></td></tr>
398 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheMaxExpire 86400 (one day)</code></td></tr>
399 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
400 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
401 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache</td></tr>
403 <p>The <code class="directive">CacheMaxExpire</code> directive specifies the maximum number of
404 seconds for which cachable HTTP documents will be retained without checking the origin
405 server. Thus, documents will be out of date at most this number of seconds. This maximum
406 value is enforced even if an expiry date was supplied with the document.</p>
408 <div class="example"><p><code>
409 CacheMaxExpire 604800
413 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
414 <div class="directive-section"><h2><a name="CacheMinExpire" id="CacheMinExpire">CacheMinExpire</a> <a name="cacheminexpire" id="cacheminexpire">Directive</a></h2>
415 <table class="directive">
416 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>The minimum time in seconds to cache a document</td></tr>
417 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheMinExpire <var>seconds</var></code></td></tr>
418 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheMinExpire 0</code></td></tr>
419 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
420 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
421 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache</td></tr>
423 <p>The <code class="directive">CacheMinExpire</code> directive specifies the minimum number of
424 seconds for which cachable HTTP documents will be retained without checking the origin
425 server. This is only used if no valid expire time was supplied with the document.</p>
428 <div class="example"><p><code>
433 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
434 <div class="directive-section"><h2><a name="CacheStoreNoStore" id="CacheStoreNoStore">CacheStoreNoStore</a> <a name="cachestorenostore" id="cachestorenostore">Directive</a></h2>
435 <table class="directive">
436 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Attempt to cache requests or responses that have been marked as no-store.</td></tr>
437 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheStoreNoStore On|Off</code></td></tr>
438 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheStoreNoStore Off</code></td></tr>
439 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
440 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
441 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache</td></tr>
443 <p>Ordinarily, requests or responses with Cache-Control: no-store header
444 values will not be stored in the cache. The
445 <code class="directive">CacheStoreNoCache</code> directive allows this
446 behavior to be overridden. <code class="directive">CacheStoreNoCache</code> On
447 tells the server to attempt to cache the resource even if it contains
448 no-store header values. Resources requiring authorization will
449 <em>never</em> be cached.</p>
451 <div class="example"><p><code>
455 <div class="warning"><h3>Warning:</h3>
456 As described in RFC 2616, the no-store directive is intended to
457 "prevent the inadvertent release or retention of sensitive information
458 (for example, on backup tapes)." Enabling this option could store
459 sensitive information in the cache. You are hereby warned.
464 <li><code class="directive"><a href="#cacheignorecachecontrol">CacheIgnoreCacheControl</a></code></li>
465 <li><code class="directive"><a href="#cachestoreprivate">CacheStorePrivate</a></code></li>
468 <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
469 <div class="directive-section"><h2><a name="CacheStorePrivate" id="CacheStorePrivate">CacheStorePrivate</a> <a name="cachestoreprivate" id="cachestoreprivate">Directive</a></h2>
470 <table class="directive">
471 <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Attempt to cache responses that the server has marked as private</td></tr>
472 <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>CacheStorePrivate On|Off</code></td></tr>
473 <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>CacheStorePrivate Off</code></td></tr>
474 <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
475 <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
476 <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_cache</td></tr>
478 <p>Ordinarily, responses with Cache-Control: private header values will not
479 be stored in the cache. The <code class="directive">CacheStorePrivate</code>
480 directive allows this behavior to be overridden.
481 <code class="directive">CacheStorePrivate</code> On
482 tells the server to attempt to cache the resource even if it contains
483 private header values. Resources requiring authorization will
484 <em>never</em> be cached.</p>
486 <div class="example"><p><code>
490 <div class="warning"><h3>Warning:</h3>
491 This directive will allow caching even if the upstream server has
492 requested that the resource not be cached. This directive is only
493 ideal for a 'private' cache.
498 <li><code class="directive"><a href="#cacheignorecachecontrol">CacheIgnoreCacheControl</a></code></li>
499 <li><code class="directive"><a href="#cachestorenostore">CacheStoreNoStore</a></code></li>
503 <div class="bottomlang">
504 <p><span>Available Languages: </span><a href="../en/mod/mod_cache.html" title="English"> en </a> |
505 <a href="../ja/mod/mod_cache.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> |
506 <a href="../ko/mod/mod_cache.html" hreflang="ko" rel="alternate" title="Korean"> ko </a></p>
507 </div><div id="footer">
508 <p class="apache">Copyright 2006 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>
509 <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>