Commit ea63cfaa authored by Graham Leggett's avatar Graham Leggett
Browse files

chuck: Docco update 

PR:
Obtained from:
Submitted by:
Reviewed by:


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@91196 13f79535-47bb-0310-9956-ffa450edef68
parent 03c44d1b

docs/manual/mod/mod_proxy.html

+3 −369
Original line number Diff line number Diff line
@@ -75,15 +75,6 @@ stability is <EM>greatly</EM> improved.<P> 
<LI><A HREF="#noproxy">NoProxy</A>

<LI><A HREF="#proxydomain">ProxyDomain</A>

<LI><A HREF="#proxyvia">ProxyVia</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="#cacheforcecompletion">CacheForceCompletion</A>

<LI><A HREF="#nocache">NoCache</A>

</UL>
@@ -770,365 +761,6 @@ additionally have the Apache server version shown as a <SAMP>Via:</SAMP> comment 


<HR>



<H2><A NAME="cacheforcecompletion">CacheForceCompletion</A> directive</H2>

<A

 HREF="directive-dict.html#Syntax"

 REL="Help"

><STRONG>Syntax:</STRONG></A> CacheForceCompletion <EM>percentage</EM><BR>

<A

 HREF="directive-dict.html#Default"

 REL="Help"

><STRONG>Default:</STRONG></A> <EM>90</EM><BR>

<A

 HREF="directive-dict.html#Context"

 REL="Help"

><STRONG>Context:</STRONG></A> server config, virtual host<BR>

<A

 HREF="directive-dict.html#Override"

 REL="Help"

><STRONG>Override:</STRONG></A> <EM>Not applicable</EM><BR>

<A

 HREF="directive-dict.html#Status"

 REL="Help"

><STRONG>Status:</STRONG></A> Base<BR>

<A

 HREF="directive-dict.html#Module"

 REL="Help"

><STRONG>Module:</STRONG></A> mod_proxy<BR>

<A

 HREF="directive-dict.html#Compatibility"

 REL="Help"

><STRONG>Compatibility:</STRONG></A> CacheForceCompletion is only available in

Apache 1.3.1 and later.<P>



If an http transfer that is being cached is cancelled, the proxy module will

complete the transfer to cache if more than the percentage specified has

already been transferred.<P>



This is a percentage, and must be a number between 1 and 100, or 0 to use

the default.  100 will cause a document to be cached only if the transfer

was allowed to complete.  A number between 60 and 90 is recommended.



<HR>



<H2><A NAME="cacheroot">CacheRoot</A> directive</H2>

<A

 HREF="directive-dict.html#Syntax"

 REL="Help"

><STRONG>Syntax:</STRONG></A> CacheRoot <EM>directory</EM><BR>

<A

 HREF="directive-dict.html#Default"

 REL="Help"

><STRONG>Default:</STRONG></A> <EM>None</EM><BR>

<A

 HREF="directive-dict.html#Context"

 REL="Help"

><STRONG>Context:</STRONG></A> server config, virtual host<BR>

<A

 HREF="directive-dict.html#Override"

 REL="Help"

><STRONG>Override:</STRONG></A> <EM>Not applicable</EM><BR>

<A

 HREF="directive-dict.html#Status"

 REL="Help"

><STRONG>Status:</STRONG></A> Base<BR>

<A

 HREF="directive-dict.html#Module"

 REL="Help"

><STRONG>Module:</STRONG></A> mod_proxy<BR>

<A

 HREF="directive-dict.html#Compatibility"

 REL="Help"

><STRONG>Compatibility:</STRONG></A> 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.

(see the <A HREF="core.html#user"><CODE>User</CODE></A> directive).<BR>

Setting <CODE>CacheRoot</CODE> enables proxy cacheing; without defining

a <CODE>CacheRoot</CODE>, proxy functionality will be available

if <CODE>ProxyRequests</CODE> are set to <CODE>On</CODE>, but no

cacheing will be available.



<HR>



<H2><A NAME="cachesize">CacheSize</A> directive</H2>

<A

 HREF="directive-dict.html#Syntax"

 REL="Help"

><STRONG>Syntax:</STRONG></A> CacheSize <EM>kilobytes</EM><BR>

<A

 HREF="directive-dict.html#Default"

 REL="Help"

><STRONG>Default:</STRONG></A> <CODE>CacheSize 5</CODE><BR>

<A

 HREF="directive-dict.html#Context"

 REL="Help"

><STRONG>Context:</STRONG></A> server config, virtual host<BR>

<A

 HREF="directive-dict.html#Override"

 REL="Help"

><STRONG>Override:</STRONG></A> <EM>Not applicable</EM><BR>

<A

 HREF="directive-dict.html#Status"

 REL="Help"

><STRONG>Status:</STRONG></A> Base<BR>

<A

 HREF="directive-dict.html#Module"

 REL="Help"

><STRONG>Module:</STRONG></A> mod_proxy<BR>

<A

 HREF="directive-dict.html#Compatibility"

 REL="Help"

><STRONG>Compatibility:</STRONG></A> 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.<BR>

Depending on the expected proxy traffic volume and <CODE>CacheGcInterval</CODE>,

use a value which is at least 20 to 40 % lower than the available space.



<HR>



<H2><A NAME="cachegcinterval">CacheGcInterval</A> directive</H2>

<A

 HREF="directive-dict.html#Syntax"

 REL="Help"

><STRONG>Syntax:</STRONG></A> CacheGcInterval <EM>hours</EM><BR>

<A

 HREF="directive-dict.html#Default"

 REL="Help"

><STRONG>Default:</STRONG></A> <EM>None</EM><BR>

<A

 HREF="directive-dict.html#Context"

 REL="Help"

><STRONG>Context:</STRONG></A> server config, virtual host<BR>

<A

 HREF="directive-dict.html#Override"

 REL="Help"

><STRONG>Override:</STRONG></A> <EM>Not applicable</EM><BR>

<A

 HREF="directive-dict.html#Status"

 REL="Help"

><STRONG>Status:</STRONG></A> Base<BR>

<A

 HREF="directive-dict.html#Module"

 REL="Help"

><STRONG>Module:</STRONG></A> mod_proxy<BR>

<A

 HREF="directive-dict.html#Compatibility"

 REL="Help"

><STRONG>Compatibility:</STRONG></A> CacheGcinterval is only available in

Apache 1.1 and later.<P>



Check the cache after the specified number of <em>hours</em>, and

delete files if the space usage is greater than that set by

CacheSize. Note that <em>hours</em> accepts a float value, you could for

example use <CODE>CacheGcInterval 1.5</CODE> to check the cache every

90 minutes. (If unset, no garbage collection will be performed, and

the cache will grow indefinitely.)  Note also that the larger the

<CODE>CacheGcInterval</CODE>, the more extra space beyond the

configured <CODE>CacheSize</CODE> will be needed for the cache between

garbage collections.<BR> <!-- Note that due to a design flaw, Apache

does not automatically force a garbage collection when the available

space on the file system where the cache resides is exhausted. -->



<HR>



<H2><A NAME="cachemaxexpire">CacheMaxExpire</A> directive</H2>

<A

 HREF="directive-dict.html#Syntax"

 REL="Help"

><STRONG>Syntax:</STRONG></A> CacheMaxExpire <EM>hours</EM><BR>

<A

 HREF="directive-dict.html#Default"

 REL="Help"

><STRONG>Default:</STRONG></A> <CODE>CacheMaxExpire 24</CODE><BR>

<A

 HREF="directive-dict.html#Context"

 REL="Help"

><STRONG>Context:</STRONG></A> server config, virtual host<BR>

<A

 HREF="directive-dict.html#Override"

 REL="Help"

><STRONG>Override:</STRONG></A> <EM>Not applicable</EM><BR>

<A

 HREF="directive-dict.html#Status"

 REL="Help"

><STRONG>Status:</STRONG></A> Base<BR>

<A

 HREF="directive-dict.html#Module"

 REL="Help"

><STRONG>Module:</STRONG></A> mod_proxy<BR>

<A

 HREF="directive-dict.html#Compatibility"

 REL="Help"

><STRONG>Compatibility:</STRONG></A> CacheMaxExpire is only available in

Apache 1.1 and later.<P>



<p>Specifies the maximum number of <em>hours</em> for which cachable HTTP

documents will be retained without checking the origin server.  Thus,

documents will be out of date at most this number of <em>hours</em>

This restriction is enforced even if an expiry date was supplied with

the document.</p>



<HR>



<H2><A NAME="cachelastmodifiedfactor">CacheLastModifiedFactor</A> directive</H2>

<A

 HREF="directive-dict.html#Syntax"

 REL="Help"

><STRONG>Syntax:</STRONG></A> CacheLastModifiedFactor <EM>factor</EM><BR>

<A

 HREF="directive-dict.html#Default"

 REL="Help"

><STRONG>Default:</STRONG></A> <CODE>CacheLastModifiedFactor 0.1</CODE><BR>

<A

 HREF="directive-dict.html#Context"

 REL="Help"

><STRONG>Context:</STRONG></A> server config, virtual host<BR>

<A

 HREF="directive-dict.html#Override"

 REL="Help"

><STRONG>Override:</STRONG></A> <EM>Not applicable</EM><BR>

<A

 HREF="directive-dict.html#Status"

 REL="Help"

><STRONG>Status:</STRONG></A> Base<BR>

<A

 HREF="directive-dict.html#Module"

 REL="Help"

><STRONG>Module:</STRONG></A> mod_proxy<BR>

<A

 HREF="directive-dict.html#Compatibility"

 REL="Help"

><STRONG>Compatibility:</STRONG></A> 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 * <em>factor</em>

</PRE>

For example, if the document was last modified 10 hours ago, and

<em>factor</em> 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.



<HR>



<H2><A NAME="cachedirlevels">CacheDirLevels</A> directive</H2>

<A

 HREF="directive-dict.html#Syntax"

 REL="Help"

><STRONG>Syntax:</STRONG></A> CacheDirLevels <EM>levels</EM><BR>

<A

 HREF="directive-dict.html#Default"

 REL="Help"

><STRONG>Default:</STRONG></A> <CODE>CacheDirLevels 3</CODE><BR>

<A

 HREF="directive-dict.html#Context"

 REL="Help"

><STRONG>Context:</STRONG></A> server config, virtual host<BR>

<A

 HREF="directive-dict.html#Override"

 REL="Help"

><STRONG>Override:</STRONG></A> <EM>Not applicable</EM><BR>

<A

 HREF="directive-dict.html#Status"

 REL="Help"

><STRONG>Status:</STRONG></A> Base<BR>

<A

 HREF="directive-dict.html#Module"

 REL="Help"

><STRONG>Module:</STRONG></A> mod_proxy<BR>

<A

 HREF="directive-dict.html#Compatibility"

 REL="Help"

><STRONG>Compatibility:</STRONG></A> CacheDirLevels is only available in

Apache 1.1 and later.<P>



CacheDirLevels sets the number of <em>levels</em> of subdirectories in

the cache.  Cached data will be saved this many directory levels below

CacheRoot.



<HR>



<H2><A NAME="cachedirlength">CacheDirLength</A> directive</H2>

<A

 HREF="directive-dict.html#Syntax"

 REL="Help"

><STRONG>Syntax:</STRONG></A> CacheDirLength <EM>length</EM><BR>

<A

 HREF="directive-dict.html#Default"

 REL="Help"

><STRONG>Default:</STRONG></A> <CODE>CacheDirLength 1</CODE><BR>

<A

 HREF="directive-dict.html#Context"

 REL="Help"

><STRONG>Context:</STRONG></A> server config, virtual host<BR>

<A

 HREF="directive-dict.html#Override"

 REL="Help"

><STRONG>Override:</STRONG></A> <EM>Not applicable</EM><BR>

<A

 HREF="directive-dict.html#Status"

 REL="Help"

><STRONG>Status:</STRONG></A> Base<BR>

<A

 HREF="directive-dict.html#Module"

 REL="Help"

><STRONG>Module:</STRONG></A> mod_proxy<BR>

<A

 HREF="directive-dict.html#Compatibility"

 REL="Help"

><STRONG>Compatibility:</STRONG></A> CacheDirLength is only available in

Apache 1.1 and later.<P>



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



<HR>



<H2><A NAME="cachedefaultexpire">CacheDefaultExpire</A> directive</H2>

<A

 HREF="directive-dict.html#Syntax"

 REL="Help"

><STRONG>Syntax:</STRONG></A> CacheDefaultExpire <EM>hours</EM><BR>

<A

 HREF="directive-dict.html#Default"

 REL="Help"

><STRONG>Default:</STRONG></A> <CODE>CacheDefaultExpire 1</CODE><BR>

<A

 HREF="directive-dict.html#Context"

 REL="Help"

><STRONG>Context:</STRONG></A> server config, virtual host<BR>

<A

 HREF="directive-dict.html#Override"

 REL="Help"

><STRONG>Override:</STRONG></A> <EM>Not applicable</EM><BR>

<A

 HREF="directive-dict.html#Status"

 REL="Help"

><STRONG>Status:</STRONG></A> Base<BR>

<A

 HREF="directive-dict.html#Module"

 REL="Help"

><STRONG>Module:</STRONG></A> mod_proxy<BR>

<A

 HREF="directive-dict.html#Compatibility"

 REL="Help"

><STRONG>Compatibility:</STRONG></A> 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 the specified number of <em>hours</em> as the expiry time.

<A HREF="#cachemaxexpire">CacheMaxExpire</A> does <STRONG>not</STRONG>

override this setting.



<HR>



<H2><A NAME="nocache">NoCache</A> directive</H2>

<A

 HREF="directive-dict.html#Syntax"
@@ -1159,8 +791,10 @@ override this setting. 
 HREF="directive-dict.html#Compatibility"

 REL="Help"

><STRONG>Compatibility:</STRONG></A> NoCache is only available in

Apache 1.1 and later.<P>

Apache 1.1 and later. In addition, in Apache 2.0 and later, it is

always on, for all hosts.



From httpd-1.3:

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