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 <H1 ALIGN="CENTER">Module mod_proxy</H1>

 This module is contained in the <code>mod_proxy.c</code> file for Apache 1.1.x,
 or the <code>modules/proxy</code> subdirectory for Apache 1.2, and
 is not compiled in by default. It provides for an <b>HTTP 1.0</b> caching proxy
 server. It is only available in Apache 1.1 and later. Common configuration
 questions are addressed <a href="#configs">here</a>.

 <h3>Note:</h3>
 <p>This module was experimental in Apache 1.1.x. As of Apache 1.2, mod_proxy
 stability is <i>greatly</i> improved.<p>

 <h2>Summary</h2>

 This module implements a proxy/cache for Apache. It implements
 proxying capability for
 <code>FTP</code>,
 <code>CONNECT</code> (for SSL),
 <code>HTTP/0.9</code>, and
 <code>HTTP/1.0</code>.
 The module can be configured to connect to other proxy modules for these
 and other protocols.

 <h2>Directives</h2>
 <ul>
 <li><a href="#proxyrequests">ProxyRequests</a>
 <li><a href="#proxyremote">ProxyRemote</a>
 <li><a href="#proxypass">ProxyPass</a>
 <li><a href="#proxyblock">ProxyBlock</a>
 <li><a href="#cacheroot">CacheRoot</a>
 <li><a href="#cachesize">CacheSize</a>
 <li><a href="#cachemaxexpire">CacheMaxExpire</a>
 <li><a href="#cachedefaultexpire">CacheDefaultExpire</a>
 <li><a href="#cachelastmodifiedfactor">CacheLastModifiedFactor</a>
 <li><a href="#cachegcinterval">CacheGcInterval</a>
 <li><a href="#cachedirlevels">CacheDirLevels</a>
 <li><a href="#cachedirlength">CacheDirLength</a>
 <li><a href="#nocache">NoCache</a>
 </ul>

 <hr>

 <A name="proxyrequests"><h2>ProxyRequests</h2></A>
 <strong>Syntax:</strong> ProxyRequests <em>on/off</em><br>
 <strong>Default:</strong> <code>ProxyRequests Off</code><br>
 <strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Base<br>
 <strong>Module:</strong> mod_proxy<br>
 <strong>Compatibility:</strong> ProxyRequest is only available in
 Apache 1.1 and later.<p>

 This allows or prevents Apache from functioning as a proxy
 server. Setting ProxyRequests to 'off' does not disable use of the <a
 href="#proxypass">ProxyPass</a> directive.

 <A name="proxyremote"><h2>ProxyRemote</h2></A>
 <strong>Syntax:</strong> ProxyRemote <em>&lt;match&gt; &lt;remote-server&gt;</em><br>
 <strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Base<br>
 <strong>Module:</strong> mod_proxy<br>
 <strong>Compatibility:</strong> ProxyRemote is only available in
 Apache 1.1 and later.<p>

 This defines remote proxies to this proxy. &lt;match&gt; is either the
 name of a URL-scheme that the remote server supports, or a partial URL
 for which the remote server should be used, or '*' to indicate the
 server should be contacted for all requests. &lt;remote-server&gt; is a
 partial URL for the remote server. Syntax:

 <pre>
   &lt;remote-server&gt; = &lt;protocol&gt;://&lt;hostname&gt;[:port]
 </pre>

 &lt;protocol&gt; is the protocol that should be used to communicate
 with the remote server; only "http" is supported by this module.

 Example:
 <pre>
   ProxyRemote http://goodguys.com/ http://mirrorguys.com:8000
   ProxyRemote * http://cleversite.com
   ProxyRemote ftp http://ftpproxy.mydomain.com:8080
 </pre>

 In the last example, the proxy will forward FTP requests, encapsulated
 as yet another HTTP proxy request, to another proxy which can handle
 them.

 <A name="proxypass"><h2>ProxyPass</h2></A>
 <strong>Syntax:</strong> ProxyPass <em>&lt;path&gt; &lt;url&gt;</em><br>
 <strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Base<br>
 <strong>Module:</strong> mod_proxy<br>
 <strong>Compatibility:</strong> ProxyPass is only available in
 Apache 1.1 and later.<p>

 This directive allows remote servers to be mapped into the space of the local
 server; the local server does not act as a proxy in the conventional sense,
 but appears to be a mirror of the remote server. &lt;path&gt; is the name of
 a local virtual path; &lt;url&gt; is a partial URL for the remote server.

 Suppose the local server has address http://wibble.org; then
 <pre>
    ProxyPass /mirror/foo http://foo.com
 </pre>
 Will cause a local request for the http://wibble.org/mirror/foo/bar to be
 internally converted into a proxy request to http://foo.com/bar

 <A name="proxyblock"><h2>ProxyBlock</h2></A>
 <strong>Syntax:</strong> ProxyBlock <em>&lt;word/host/domain list&gt;</em><br>
 <strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Base<br>
 <strong>Module:</strong> mod_proxy<br>
 <strong>Compatibility:</strong> ProxyBlock is only available in
 Apache 1.2 and later.<p>

 The ProxyBlock directive specifies a list of words, hosts and/or domains,
 separated by spaces. HTTP, HTTPS, and FTP document requests to matched words,
 hosts or domains are <em>blocked</em> by the proxy server. The proxy module
 will also attempt to determine IP addresses of list items which may be
 hostnames during startup, and cache them for match test as well. Example:

 <pre>
   ProxyBlock joes_garage.com some_host.co.uk rocky.wotsamattau.edu
 </pre>

 'rocky.wotsamattau.edu' would also be matched if referenced by IP address.<p>

 Note that 'wotsamattau' would also be sufficient to match 'wotsamattau.edu'.<p>

 Note also that

 <pre>
 ProxyBlock *
 </pre>

 blocks connections to all sites.

 <A name="cacheroot"><h2>CacheRoot</h2></A>
 <strong>Syntax:</strong> CacheRoot <em>&lt;directory&gt;</em><br>
 <strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Base<br>
 <strong>Module:</strong> mod_proxy<br>
 <strong>Compatibility:</strong> CacheRoot is only available in
 Apache 1.1 and later.<p>

 Sets the name of the directory to contain cache files; this must be
 writable
 by the httpd server.

 <A name="cachesize"><h2>CacheSize</h2></A>
 <strong>Syntax:</strong> CacheSize <em>&lt;size&gt;</em><br>
 <strong>Default:</strong> <code>CacheSize 5</code><br>
 <strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Base<br>
 <strong>Module:</strong> mod_proxy<br>
 <strong>Compatibility:</strong> CacheSize is only available in
 Apache 1.1 and later.<p>

 Sets the desired space usage of the cache, in Kb (1024 byte units). Although
 usage may grow above this setting, the garbage collection will delete files
 until the usage is at or below this setting.

 <A name="cachegcinterval"><h2>CacheGcInterval</h2></A>
 <strong>Syntax:</strong> CacheGcInterval <em>&lt;time&gt;</em><br>
 <strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Base<br>
 <strong>Module:</strong> mod_proxy<br>
 <strong>Compatibility:</strong> CacheGcinterval is only available in
 Apache 1.1 and later.<p>

 Check the cache every &lt;time&gt; hours, and delete files if the space
 usage is greater than that set by CacheSize.

 <A name="cachemaxexpire"><h2>CacheMaxExpire</h2></A>
 <strong>Syntax:</strong> CacheMaxExpire <em>&lt;time&gt;</em><br>
 <strong>Default:</strong> <code>CacheMaxExpire 24</code><br>
 <strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Base<br>
 <strong>Module:</strong> mod_proxy<br>
 <strong>Compatibility:</strong> CacheMaxExpire is only available in
 Apache 1.1 and later.<p>

 Cachable HTTP documents will be retained for at most &lt;time&gt; hours without
 checking the origin server. Thus documents can be at most &lt;time&gt;
 hours out of date. This restriction is enforced even if an expiry date
 was supplied with the document.

 <A name="cachelastmodifiedfactor"><h2>CacheLastModifiedFactor</h2></A>
 <strong>Syntax:</strong> CacheLastModifiedFactor <em>&lt;factor&gt;</em><br>
 <strong>Default:</strong> <code>CacheLastModifiedFactor 0.1</code><br>
 <strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Base<br>
 <strong>Module:</strong> mod_proxy<br>
 <strong>Compatibility:</strong> CacheLastModifiedFactor is only available in
 Apache 1.1 and later.<p>

 If the origin HTTP server did not supply an expiry date for the
 document, then estimate one using the formula
 <pre>
   expiry-period = time-since-last-modification * &lt;factor&gt;
 </pre>
 For example, if the document was last modified 10 hours ago, and
 &lt;factor&gt; is 0.1, then the expiry period will be set to 10*0.1 = 1 hour.

 <p>If the expiry-period would be longer than that set by CacheMaxExpire,
 then the latter takes precedence.

 <A name="cachedirlevels"><h2>CacheDirLevels</h2></A>
 <strong>Syntax:</strong> CacheDirLevels <em>&lt;levels&gt;</em><br>
 <strong>Default:</strong> <code>CacheDirLevels 3</code><br>
 <strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Base<br>
 <strong>Module:</strong> mod_proxy<br>
 <strong>Compatibility:</strong> CacheDirLevels is only available in
 Apache 1.1 and later.<p>

 CacheDirLevels sets the number of levels of subdirectories in the cache.
 Cached data will be saved this many directory levels below CacheRoot.

 <A name="cachedirlength"><h2>CacheDirLength</h2></A>
 <strong>Syntax:</strong> CacheDirLength <em>&lt;length&gt;</em><br>
 <strong>Default:</strong> <code>CacheDirLength 1</code><br>
 <strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Base<br>
 <strong>Module:</strong> mod_proxy<br>
 <strong>Compatibility:</strong> CacheDirLength is only available in
 Apache 1.1 and later.<p>

 CacheDirLength sets the number of characters in proxy cache subdirectory names.

 <A name="cachedefaultexpire"><h2>CacheDefaultExpire</h2></A>
 <strong>Syntax:</strong> CacheDefaultExpire <em>&lt;time&gt;</em><br>
 <strong>Default:</strong> <code>CacheDefaultExpire 1</code><br>
 <strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Base<br>
 <strong>Module:</strong> mod_proxy<br>
 <strong>Compatibility:</strong> CacheDefaultExpire is only available in
 Apache 1.1 and later.<p>

 If the document is fetched via a protocol that does not support expiry times,
 then use &lt;time&gt; hours as the expiry time.
 <a href="#cachemaxexpire">CacheMaxExpire</a> does <strong>not</strong>
 override.

 <A name="nocache"><h2>NoCache</h2></A>
 <strong>Syntax:</strong> NoCache <em>&lt;word/host/domain list&gt;</em><br>
 <strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Base<br>
 <strong>Module:</strong> mod_proxy<br>
 <strong>Compatibility:</strong> NoCache is only available in
 Apache 1.1 and later.<p>

 The NoCache directive specifies a list of words, hosts and/or domains, separated
 by spaces. HTTP and non-passworded FTP documents from matched words, hosts or
 domains are <em>not</em> cached by the proxy server. The proxy module will
 also attempt to determine IP addresses of list items which may be hostnames
 during startup, and cache them for match test as well. Example:

 <pre>
   NoCache joes_garage.com some_host.co.uk bullwinkle.wotsamattau.edu
 </pre>

 'bullwinkle.wotsamattau.edu' would also be matched if referenced by IP
 address.<p>

 Note that 'wotsamattau' would also be sufficient to match 'wotsamattau.edu'.<p>

 Note also that

 <pre>
 NoCache *
 </pre>

 disables caching completely.<p>

 <hr>

 <a name="configs"><h2>Common configuration topics</h2></a>

 <ul>
 <li><a href="#access">Controlling access to your proxy</a>
 <li><a href="#shortname">Using Netscape hostname shortcuts</a>
 <li><a href="#mimetypes">Why doesn't file type <i>xxx</i> download via FTP?</a>
 <li><a href="#startup">Why does Apache start more slowly when using the
         proxy module?</a>
 <li><a href="#socks">Can I use the Apache proxy module with my SOCKS proxy?</a>
 </ul>

 <h2><a name="access">Controlling access to your proxy</a></h2>

 You can control who can access your proxy via the normal &lt;Directory&gt;
 control block using the following example:<p>

 <pre>
 &lt;Directory proxy:*&gt;
 &lt;Limit GET PUT POST DELETE CONNECT OPTIONS&gt;
 order deny,allow
 deny from [machines you'd like *not* to allow by IP address or name]
 allow from [machines you'd like to allow by IP address or name]
 &lt;/Limit&gt;
 &lt;/Directory&gt;
 </pre><p>

 A &lt;Files&gt; block will also work, and is the only method known to work
 for all possible URLs in Apache versions earlier than 1.2b10.<p>

 <h2><a name="shortname">Using Netscape hostname shortcuts</a></h2>

 There is an optional patch to the proxy module to allow Netscape-like
 hostname shortcuts to be used. It's available
 <a href="http://www.apache.org/dist/contrib/patches/1.2/netscapehost.patch">
 here</a>.<p>

 <h2><a name="mimetypes">Why doesn't file type <i>xxx</i> download via FTP?</a></h2>

 You probably don't have that particular file type defined as
 <i>application/octet-stream</i> in your proxy's mime.types configuration
 file. A useful line can be<p>

 <pre>
 application/octet-stream        bin dms lha lzh exe class tgz taz
 </pre>

 <h2><a name="startup">Why does Apache start more slowly when using the
         proxy module?</a></h2>

 If you're using the <code>ProxyBlock</code> or <code>NoCache</code>
 directives, hostnames' IP addresses are looked up and cached during
 startup for later match test. This may take a few seconds (or more)
 depending on the speed with which the hostname lookups occur.<p>

 <h2><a name="socks">Can I use the Apache proxy module with my SOCKS proxy?</a></h2>

 Yes. Just build Apache with the rule <code>SOCKS4=yes</code> in your
 <i>Configuration</i> file, and follow the instructions there. SOCKS5
 capability can be added in a similar way (there's no <code>SOCKS5</code>
 rule yet), so use the <code>EXTRA_LFLAGS</code> definition, or build Apache
 normally and run it with the <i>runsocks</i> wrapper provided with SOCKS5,
 if your OS supports dynamically linked libraries.<p>

 Some users have reported problems when using SOCKS version 4.2 on Solaris.
 The problem was solved by upgrading to SOCKS 4.3.<p>

 Remember that you'll also have to grant access to your Apache proxy machine by
 permitting connections on the appropriate ports in your SOCKS daemon's
 configuration.<p>

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	<H1 ALIGN="CENTER">Module mod_proxy</H1>

	This module is contained in the <code>mod_proxy.c</code> file for Apache 1.1.x,
	or the <code>modules/proxy</code> subdirectory for Apache 1.2, and
	is not compiled in by default. It provides for an <b>HTTP 1.0</b> caching proxy
	server. It is only available in Apache 1.1 and later. Common configuration
	questions are addressed <a href="#configs">here</a>.

	<h3>Note:</h3>
	<p>This module was experimental in Apache 1.1.x. As of Apache 1.2, mod_proxy
	stability is <i>greatly</i> improved.<p>

	<h2>Summary</h2>

	This module implements a proxy/cache for Apache. It implements
	proxying capability for
	<code>FTP</code>,
	<code>CONNECT</code> (for SSL),
	<code>HTTP/0.9</code>, and
	<code>HTTP/1.0</code>.
	The module can be configured to connect to other proxy modules for these
	and other protocols.

	<h2>Directives</h2>
	<ul>
	<li><a href="#proxyrequests">ProxyRequests</a>
	<li><a href="#proxyremote">ProxyRemote</a>
	<li><a href="#proxypass">ProxyPass</a>
	<li><a href="#proxyblock">ProxyBlock</a>
	<li><a href="#cacheroot">CacheRoot</a>
	<li><a href="#cachesize">CacheSize</a>
	<li><a href="#cachemaxexpire">CacheMaxExpire</a>
	<li><a href="#cachedefaultexpire">CacheDefaultExpire</a>
	<li><a href="#cachelastmodifiedfactor">CacheLastModifiedFactor</a>
	<li><a href="#cachegcinterval">CacheGcInterval</a>
	<li><a href="#cachedirlevels">CacheDirLevels</a>
	<li><a href="#cachedirlength">CacheDirLength</a>
	<li><a href="#nocache">NoCache</a>
	</ul>

	<hr>

	<A name="proxyrequests"><h2>ProxyRequests</h2></A>
	<strong>Syntax:</strong> ProxyRequests <em>on/off</em><br>
	<strong>Default:</strong> <code>ProxyRequests Off</code><br>
	<strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Base<br>
	<strong>Module:</strong> mod_proxy<br>
	<strong>Compatibility:</strong> ProxyRequest is only available in
	Apache 1.1 and later.<p>

	This allows or prevents Apache from functioning as a proxy
	server. Setting ProxyRequests to 'off' does not disable use of the <a
	href="#proxypass">ProxyPass</a> directive.

	<A name="proxyremote"><h2>ProxyRemote</h2></A>
	<strong>Syntax:</strong> ProxyRemote <em><match> <remote-server></em><br>
	<strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Base<br>
	<strong>Module:</strong> mod_proxy<br>
	<strong>Compatibility:</strong> ProxyRemote is only available in
	Apache 1.1 and later.<p>

	This defines remote proxies to this proxy. <match> is either the
	name of a URL-scheme that the remote server supports, or a partial URL
	for which the remote server should be used, or '*' to indicate the
	server should be contacted for all requests. <remote-server> is a
	partial URL for the remote server. Syntax:

	<pre>
	<remote-server> = <protocol>://<hostname>[:port]
	</pre>

	<protocol> is the protocol that should be used to communicate
	with the remote server; only "http" is supported by this module.

	Example:
	<pre>
	ProxyRemote http://goodguys.com/ http://mirrorguys.com:8000
	ProxyRemote * http://cleversite.com
	ProxyRemote ftp http://ftpproxy.mydomain.com:8080
	</pre>

	In the last example, the proxy will forward FTP requests, encapsulated
	as yet another HTTP proxy request, to another proxy which can handle
	them.

	<A name="proxypass"><h2>ProxyPass</h2></A>
	<strong>Syntax:</strong> ProxyPass <em><path> <url></em><br>
	<strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Base<br>
	<strong>Module:</strong> mod_proxy<br>
	<strong>Compatibility:</strong> ProxyPass is only available in
	Apache 1.1 and later.<p>

	This directive allows remote servers to be mapped into the space of the local
	server; the local server does not act as a proxy in the conventional sense,
	but appears to be a mirror of the remote server. <path> is the name of
	a local virtual path; <url> is a partial URL for the remote server.

	Suppose the local server has address http://wibble.org; then
	<pre>
	ProxyPass /mirror/foo http://foo.com
	</pre>
	Will cause a local request for the http://wibble.org/mirror/foo/bar to be
	internally converted into a proxy request to http://foo.com/bar

	<A name="proxyblock"><h2>ProxyBlock</h2></A>
	<strong>Syntax:</strong> ProxyBlock <em><word/host/domain list></em><br>
	<strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Base<br>
	<strong>Module:</strong> mod_proxy<br>
	<strong>Compatibility:</strong> ProxyBlock is only available in
	Apache 1.2 and later.<p>

	The ProxyBlock directive specifies a list of words, hosts and/or domains,
	separated by spaces. HTTP, HTTPS, and FTP document requests to matched words,
	hosts or domains are <em>blocked</em> by the proxy server. The proxy module
	will also attempt to determine IP addresses of list items which may be
	hostnames during startup, and cache them for match test as well. Example:

	<pre>
	ProxyBlock joes_garage.com some_host.co.uk rocky.wotsamattau.edu
	</pre>

	'rocky.wotsamattau.edu' would also be matched if referenced by IP address.<p>

	Note that 'wotsamattau' would also be sufficient to match 'wotsamattau.edu'.<p>

	Note also that

	<pre>
	ProxyBlock *
	</pre>

	blocks connections to all sites.

	<A name="cacheroot"><h2>CacheRoot</h2></A>
	<strong>Syntax:</strong> CacheRoot <em><directory></em><br>
	<strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Base<br>
	<strong>Module:</strong> mod_proxy<br>
	<strong>Compatibility:</strong> CacheRoot is only available in
	Apache 1.1 and later.<p>

	Sets the name of the directory to contain cache files; this must be
	writable
	by the httpd server.

	<A name="cachesize"><h2>CacheSize</h2></A>
	<strong>Syntax:</strong> CacheSize <em><size></em><br>
	<strong>Default:</strong> <code>CacheSize 5</code><br>
	<strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Base<br>
	<strong>Module:</strong> mod_proxy<br>
	<strong>Compatibility:</strong> CacheSize is only available in
	Apache 1.1 and later.<p>

	Sets the desired space usage of the cache, in Kb (1024 byte units). Although
	usage may grow above this setting, the garbage collection will delete files
	until the usage is at or below this setting.

	<A name="cachegcinterval"><h2>CacheGcInterval</h2></A>
	<strong>Syntax:</strong> CacheGcInterval <em><time></em><br>
	<strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Base<br>
	<strong>Module:</strong> mod_proxy<br>
	<strong>Compatibility:</strong> CacheGcinterval is only available in
	Apache 1.1 and later.<p>

	Check the cache every <time> hours, and delete files if the space
	usage is greater than that set by CacheSize.

	<A name="cachemaxexpire"><h2>CacheMaxExpire</h2></A>
	<strong>Syntax:</strong> CacheMaxExpire <em><time></em><br>
	<strong>Default:</strong> <code>CacheMaxExpire 24</code><br>
	<strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Base<br>
	<strong>Module:</strong> mod_proxy<br>
	<strong>Compatibility:</strong> CacheMaxExpire is only available in
	Apache 1.1 and later.<p>

	Cachable HTTP documents will be retained for at most <time> hours without
	checking the origin server. Thus documents can be at most <time>
	hours out of date. This restriction is enforced even if an expiry date
	was supplied with the document.

	<A name="cachelastmodifiedfactor"><h2>CacheLastModifiedFactor</h2></A>
	<strong>Syntax:</strong> CacheLastModifiedFactor <em><factor></em><br>
	<strong>Default:</strong> <code>CacheLastModifiedFactor 0.1</code><br>
	<strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Base<br>
	<strong>Module:</strong> mod_proxy<br>
	<strong>Compatibility:</strong> CacheLastModifiedFactor is only available in
	Apache 1.1 and later.<p>

	If the origin HTTP server did not supply an expiry date for the
	document, then estimate one using the formula
	<pre>
	expiry-period = time-since-last-modification * <factor>
	</pre>
	For example, if the document was last modified 10 hours ago, and
	<factor> is 0.1, then the expiry period will be set to 10*0.1 = 1 hour.

	<p>If the expiry-period would be longer than that set by CacheMaxExpire,
	then the latter takes precedence.

	<A name="cachedirlevels"><h2>CacheDirLevels</h2></A>
	<strong>Syntax:</strong> CacheDirLevels <em><levels></em><br>
	<strong>Default:</strong> <code>CacheDirLevels 3</code><br>
	<strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Base<br>
	<strong>Module:</strong> mod_proxy<br>
	<strong>Compatibility:</strong> CacheDirLevels is only available in
	Apache 1.1 and later.<p>

	CacheDirLevels sets the number of levels of subdirectories in the cache.
	Cached data will be saved this many directory levels below CacheRoot.

	<A name="cachedirlength"><h2>CacheDirLength</h2></A>
	<strong>Syntax:</strong> CacheDirLength <em><length></em><br>
	<strong>Default:</strong> <code>CacheDirLength 1</code><br>
	<strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Base<br>
	<strong>Module:</strong> mod_proxy<br>
	<strong>Compatibility:</strong> CacheDirLength is only available in
	Apache 1.1 and later.<p>

	CacheDirLength sets the number of characters in proxy cache subdirectory names.

	<A name="cachedefaultexpire"><h2>CacheDefaultExpire</h2></A>
	<strong>Syntax:</strong> CacheDefaultExpire <em><time></em><br>
	<strong>Default:</strong> <code>CacheDefaultExpire 1</code><br>
	<strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Base<br>
	<strong>Module:</strong> mod_proxy<br>
	<strong>Compatibility:</strong> CacheDefaultExpire is only available in
	Apache 1.1 and later.<p>

	If the document is fetched via a protocol that does not support expiry times,
	then use <time> hours as the expiry time.
	<a href="#cachemaxexpire">CacheMaxExpire</a> does <strong>not</strong>
	override.

	<A name="nocache"><h2>NoCache</h2></A>
	<strong>Syntax:</strong> NoCache <em><word/host/domain list></em><br>
	<strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Base<br>
	<strong>Module:</strong> mod_proxy<br>
	<strong>Compatibility:</strong> NoCache is only available in
	Apache 1.1 and later.<p>

	The NoCache directive specifies a list of words, hosts and/or domains, separated
	by spaces. HTTP and non-passworded FTP documents from matched words, hosts or
	domains are <em>not</em> cached by the proxy server. The proxy module will
	also attempt to determine IP addresses of list items which may be hostnames
	during startup, and cache them for match test as well. Example:

	<pre>
	NoCache joes_garage.com some_host.co.uk bullwinkle.wotsamattau.edu
	</pre>

	'bullwinkle.wotsamattau.edu' would also be matched if referenced by IP
	address.<p>

	Note that 'wotsamattau' would also be sufficient to match 'wotsamattau.edu'.<p>

	Note also that

	<pre>
	NoCache *
	</pre>

	disables caching completely.<p>

	<hr>

	<a name="configs"><h2>Common configuration topics</h2></a>

	<ul>
	<li><a href="#access">Controlling access to your proxy</a>
	<li><a href="#shortname">Using Netscape hostname shortcuts</a>
	<li><a href="#mimetypes">Why doesn't file type <i>xxx</i> download via FTP?</a>
	<li><a href="#startup">Why does Apache start more slowly when using the
	proxy module?</a>
	<li><a href="#socks">Can I use the Apache proxy module with my SOCKS proxy?</a>
	</ul>

	<h2><a name="access">Controlling access to your proxy</a></h2>

	You can control who can access your proxy via the normal <Directory>
	control block using the following example:<p>

	<pre>
	<Directory proxy:*>
	<Limit GET PUT POST DELETE CONNECT OPTIONS>
	order deny,allow
	deny from [machines you'd like not to allow by IP address or name]
	allow from [machines you'd like to allow by IP address or name]
	</Limit>
	</Directory>
	</pre><p>

	A <Files> block will also work, and is the only method known to work
	for all possible URLs in Apache versions earlier than 1.2b10.<p>

	<h2><a name="shortname">Using Netscape hostname shortcuts</a></h2>

	There is an optional patch to the proxy module to allow Netscape-like
	hostname shortcuts to be used. It's available
	<a href="http://www.apache.org/dist/contrib/patches/1.2/netscapehost.patch">
	here</a>.<p>

	<h2><a name="mimetypes">Why doesn't file type <i>xxx</i> download via FTP?</a></h2>

	You probably don't have that particular file type defined as
	<i>application/octet-stream</i> in your proxy's mime.types configuration
	file. A useful line can be<p>

	<pre>
	application/octet-stream bin dms lha lzh exe class tgz taz
	</pre>

	<h2><a name="startup">Why does Apache start more slowly when using the
	proxy module?</a></h2>

	If you're using the <code>ProxyBlock</code> or <code>NoCache</code>
	directives, hostnames' IP addresses are looked up and cached during
	startup for later match test. This may take a few seconds (or more)
	depending on the speed with which the hostname lookups occur.<p>

	<h2><a name="socks">Can I use the Apache proxy module with my SOCKS proxy?</a></h2>

	Yes. Just build Apache with the rule <code>SOCKS4=yes</code> in your
	<i>Configuration</i> file, and follow the instructions there. SOCKS5
	capability can be added in a similar way (there's no <code>SOCKS5</code>
	rule yet), so use the <code>EXTRA_LFLAGS</code> definition, or build Apache
	normally and run it with the <i>runsocks</i> wrapper provided with SOCKS5,
	if your OS supports dynamically linked libraries.<p>

	Some users have reported problems when using SOCKS version 4.2 on Solaris.
	The problem was solved by upgrading to SOCKS 4.3.<p>

	Remember that you'll also have to grant access to your Apache proxy machine by
	permitting connections on the appropriate ports in your SOCKS daemon's
	configuration.<p>

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