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From build...@apache.org
Subject svn commit: r789093 - in /websites/staging/trafficserver/trunk/content/docs/trunk/admin: configuration-files/records.config.en.html http-proxy-caching/index.en.html
Date Tue, 03 May 2011 00:35:12 GMT
Author: buildbot
Date: Tue May  3 00:35:12 2011
New Revision: 789093

Log:
Staging update by buildbot

Modified:
    websites/staging/trafficserver/trunk/content/docs/trunk/admin/configuration-files/records.config.en.html
    websites/staging/trafficserver/trunk/content/docs/trunk/admin/http-proxy-caching/index.en.html

Modified: websites/staging/trafficserver/trunk/content/docs/trunk/admin/configuration-files/records.config.en.html
==============================================================================
--- websites/staging/trafficserver/trunk/content/docs/trunk/admin/configuration-files/records.config.en.html (original)
+++ websites/staging/trafficserver/trunk/content/docs/trunk/admin/configuration-files/records.config.en.html Tue May  3 00:35:12 2011
@@ -1225,17 +1225,18 @@ problems with caching and your origin se
 <dl>
 <dt id="proxy.config.http.cache.heuristic_min_lifetime"><em><code>proxy.config.http.cache.heuristic_min_lifetime</code></em></dt>
 <dd><code>INT</code></dd>
-<dd>Default: <code>3600</code></dd>
-<dd>The minimum amount of time a document in the cache is considered to
-be fresh.</dd>
+<dd>Default: <code>3600</code> (1 hour)</dd>
+<dd>The minimum amount of time an HTTP object without an expiration datecan remain fresh in the cache
+before is considered to be stale.</dd>
 <dt id="proxy.config.http.cache.heuristic_max_lifetime"><em><code>proxy.config.http.cache.heuristic_max_lifetime</code></em></dt>
 <dd><code>INT</code></dd>
-<dd>Default: <code>86400</code></dd>
+<dd>Default: <code>86400</code> (1 day)</dd>
 <dd>The maximum amount of time a document in the cache remains fresh.</dd>
 <dt id="proxy.config.http.cache.heuristic_lm_factor"><em><code>proxy.config.http.cache.heuristic_lm_factor</code></em></dt>
 <dd><code>FLOAT</code></dd>
 <dd>Default: <code>0.10000</code></dd>
-<dd>The aging factor for freshness computations.</dd>
+<dd>The aging factor for freshness computations.
+Traffic Server stores an object for this percentage of the time that elapsed since it last changed.</dd>
 <dt id="proxy.config.http.cache.fuzz.time"><em><code>proxy.config.http.cache.fuzz.time</code></em></dt>
 <dd><code>INT</code></dd>
 <dd>Default: <code>240</code></dd>

Modified: websites/staging/trafficserver/trunk/content/docs/trunk/admin/http-proxy-caching/index.en.html
==============================================================================
--- websites/staging/trafficserver/trunk/content/docs/trunk/admin/http-proxy-caching/index.en.html (original)
+++ websites/staging/trafficserver/trunk/content/docs/trunk/admin/http-proxy-caching/index.en.html Tue May  3 00:35:12 2011
@@ -58,30 +58,42 @@ other tasks. </p>
 </ul>
 <h2 id="UnderstandingHTTPWebProxyCaching">Understanding HTTP Web Proxy Caching</h2>
 <p>Internet users direct their requests to web servers all over the Internet. 
-A caching server must act as a <strong>web proxy server </strong>so it can serve those requests. 
+A caching server must act as a <strong>web proxy server</strong> so it can serve those requests. 
 After a web proxy server receives requests for web objects, it either serves 
 the requests or forwards them to the <strong>origin server</strong> (the web server that 
 contains the original copy of the requested information). The Traffic Server 
 proxy supports <strong>explicit proxy caching</strong>, in which the user’s client software 
 must be configured to send requests directly to the Traffic Server proxy. The 
 following overview illustrates how Traffic Server serves a user request.</p>
-<p><strong>Step 1</strong> Traffic Server receives a user request for a web object. </p>
-<p><strong>Step 2</strong> Using the object address, Traffic Server tries to locate the requested 
+<ol>
+<li>
+<p>Traffic Server receives a user request for a web object. </p>
+</li>
+<li>
+<p>Using the object address, Traffic Server tries to locate the requested 
 object in its object database (<strong>cache</strong>). </p>
-<p><strong>Step 3</strong> If the object is in the cache, then Traffic Server checks to see 
+</li>
+<li>
+<p>If the object is in the cache, then Traffic Server checks to see 
 if the object is fresh enough to serve. If it is fresh, then Traffic Server 
 serves it to the user as a <strong>cache hit</strong> (see the figure below).</p>
 <p><img alt="A cache hit" src="/images/admin/cache_hit.jpg" /></p>
-<p><strong>Step 4</strong> If the data in the cache is stale, then Traffic Server connects 
+</li>
+<li>
+<p>If the data in the cache is stale, then Traffic Server connects 
 to the origin server and checks if the object is still fresh (a <strong>revalidation</strong>). 
 If it is, then Traffic Server immediately sends the cached copy to the user. </p>
-<p><strong>Step 5</strong> If the object is not in the cache (a <strong>cache miss</strong>) or if the server 
+</li>
+<li>
+<p>If the object is not in the cache (a <strong>cache miss</strong>) or if the server 
 indicates the cached copy is no longer valid, then Traffic Server obtains the 
 object from the origin server. The object is then simultaneously streamed to 
 the user and the Traffic Server local cache (see the figure below). Subsequent 
 requests for the object can be served faster because the object is retrieved 
 directly from cache.</p>
 <p><img alt="A cache miss" src="/images/admin/cache_miss.jpg" /></p>
+</li>
+</ol>
 <p>Caching is typically more complex than the preceding overview suggests. In 
 particular, the overview does not discuss how Traffic Server ensures freshness, 
 serves correct HTTP alternates, and treats requests for objects that cannot/should 
@@ -98,50 +110,56 @@ origin server to see if an object is sti
 <h2 id="HTTPObjectFreshness">HTTP Object Freshness</h2>
 <p>Traffic Server determines whether an HTTP object in the cache is fresh by: </p>
 <ul>
-<li><strong>Checking the <code>Expires</code> or </strong><code>**max**</code><strong><code>-age</code> header</strong><br />
- Some HTTP objects contain <code>Expires</code> headers or <code>max-age</code> headers that explicitly define how long the object can be cached. Traffic Server compares the current time with the expiration time to determine if the object is still fresh.</li>
-<li><strong>Checking the <code>Last-Modified / Date</code> header</strong><br />
- If an HTTP object has no <code>Expires</code> header or <code>max-age</code> header, then Traffic Server can calculate a freshness limit using the following formula: <br />
-<code>freshness_limit =(_date - last_modified_) * 0.10</code> <br />
- where<code>_date_</code> is the date in the object’s server response header and <code>_last_modified _</code> is the date in the <code>Last-Modified</code> header. If there is no <code>Last-Modified</code> header, then Traffic Server uses the date the object was written to cache. The value <code>0.10</code> (10 percent) can be increased or reduced to better suit your needs (refer to <a href="#ModifyingAgingFactorFreshnessComputations">Modifying the Aging Factor for Freshness Computations</a>).<br />
- The computed freshness limit is bound by a minimum and maximum value - refer to <a href="#SettingAbsoluteFreshnessLimit">Setting an Absolute Freshness Limit</a> for more information.</li>
-<li><strong>Checking the absolute freshness limit </strong><br />
- For HTTP objects that do not have <code>Expires</code> headers or do not have both <code>Last-Modified</code> and <code>Date</code> headers, Traffic Server uses a maximum and minimum freshness limit (efer to <a href="#SettingAbsoluteFreshnessLimit">Setting an Absolute Freshness Limit</a>).</li>
-<li><strong>Checking revalidate rules in the <code>cache.config</code> file</strong><br />
- Revalidate rules apply freshness limits to specific HTTP objects. You can set freshness limits for objects originating from particular domains or IP addresses, objects with URLs that contain specified regular expressions, objects requested by particular clients, and so on (refer to <a href="files.htm#cache.config">cache.config</a>).</li>
-</ul>
-<h3 id="ModifyingAgingFactorforFreshnessComputations">Modifying the Aging Factor for Freshness Computations</h3>
-<p>If an object does not contain any expiration information, then Traffic Server 
-can estimate its freshness from the <code>Last-Modified</code> and <code>Date</code> headers. By 
-default, Traffic Server stores an object for 10% of the time that elapsed since 
-it last changed. You can increase or reduce the percentage according to your 
-needs. </p>
-<h5 id="modifyagingfactorforfreshnesscomputations">To modify the aging factor for freshness computations:</h5>
-<ol>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variable:</li>
 <li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><code>_proxy.config.http.cache.heuristic_lm_factor_</code></dt>
-<dd />
-</dl>
-<div class="codehilite"><pre><span class="n">Set</span> <span class="n">this</span> <span class="n">variable</span> <span class="n">to</span> <span class="n">specify</span> <span class="n">the</span> <span class="n">aging</span> <span class="n">factor</span> <span class="k">for</span> <span class="n">freshness</span> <span class="n">computations</span><span class="o">.</span> <span class="n">Traffic</span> <span class="n">Server</span> <span class="n">stores</span> <span class="n">an</span> <span class="n">object</span> <span class="k">for</span> <span class="n">this</span> <span class="n">percentage</span> <span class="n">of</span> <span class="n">the</span> <span class="nb">time</span> <span class="n">that</span> <span class="n">elapsed</span> <span class="n">since</span> <span class="n">it</span> <span class="k">last</span> <span class="n">changed</span><span class="o">.</span>   
- <span class="n">The</span> <span class="n">default</span> <span class="n">value</span> <span class="n">is</span> <span class="mf">0.10</span> <span class="p">(</span><span class="mi">10</span> <span class="n">percent</span><span class="p">)</span><span class="o">.</span>
+<p><strong>Checking the <code>Expires</code> or <code>max-age</code> header</strong></p>
+<p>Some HTTP objects contain <code>Expires</code> headers or <code>max-age</code> headers that
+explicitly define how long the object can be cached. Traffic Server
+compares the current time with the expiration time to determine if the
+object is still fresh.</p>
+</li>
+<li>
+<p><strong>Checking the <code>Last-Modified</code> / <code>Date</code> header</strong></p>
+<p>If an HTTP object has no <code>Expires</code> header or <code>max-age</code> header, then
+Traffic Server can calculate a freshness limit using the following formula: <br />
+</p>
+<div class="codehilite"><pre><span class="n">freshness_limit</span> <span class="o">=</span> <span class="p">(</span> <span class="n">date</span> <span class="o">-</span> <span class="n">last_modified</span> <span class="p">)</span> <span class="o">*</span> <span class="mf">0.10</span>
 </pre></div>
 
 
+<p>where <em><code>date</code></em> is the date in the object's server response header and <em><code>last_modified</code></em>
+is the date in the <code>Last-Modified</code> header. If there is no <code>Last-Modified</code> header, then
+Traffic Server uses the date the object was written to cache. The value <code>0.10</code>
+(10 percent) can be increased or reduced to better suit your needs (refer to
+<a href="#ModifyingAgingFactorFreshnessComputations">Modifying the Aging Factor for Freshness Computations</a>).<br />
+</p>
+<p>The computed freshness limit is bound by a minimum and maximum value - refer to
+<a href="#SettingAbsoluteFreshnessLimit">Setting an Absolute Freshness Limit</a> for more information.</p>
 </li>
 <li>
-<p>Save and close the <code>records.config</code> file.</p>
-</li>
-<li>
-<p>Navigate to the Traffic Server <code>bin</code> directory. <br />
-</p>
+<p><strong>Checking the absolute freshness limit</strong></p>
+<p>For HTTP objects that do not have <code>Expires</code> headers or do not have both <code>Last-Modified</code>
+and <code>Date</code> headers, Traffic Server uses a maximum and minimum freshness limit
+(refer to <a href="#SettingAbsoluteFreshnessLimit">Setting an Absolute Freshness Limit</a>).</p>
 </li>
 <li>
-<p>Run the <code>traffic_line -x</code> command to apply the configuration changes.</p>
+<p><strong>Checking revalidate rules in the <code>cache.config</code> file</strong></p>
+<p>Revalidate rules apply freshness limits to specific HTTP objects. You can set freshness
+limits for objects originating from particular domains or IP addresses, objects with URLs
+that contain specified regular expressions, objects requested by particular clients,
+and so on (refer to <a href="files.htm#cache.config">cache.config</a>).</p>
 </li>
+</ul>
+<h3 id="ModifyingAgingFactorFreshnessComputations">Modifying the Aging Factor for Freshness Computations</h3>
+<p>If an object does not contain any expiration information, then Traffic Server 
+can estimate its freshness from the <code>Last-Modified</code> and <code>Date</code> headers. By 
+default, Traffic Server stores an object for 10% of the time that elapsed since 
+it last changed. You can increase or reduce the percentage according to your 
+needs. </p>
+<h5 id="modifyagingfactorfreshnesscomputations">To modify the aging factor for freshness computations:</h5>
+<ol>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.http.cache.heuristic_lm_factor"><em><code>proxy.config.http.cache.heuristic_lm_factor</code></em></a></li>
+<li>Run the <code>traffic_line -x</code> command to apply the configuration changes.</li>
 </ol>
 <h3 id="SettinganAbsoluteFreshnessLimit">Setting an Absolute Freshness Limit</h3>
 <p>Some objects do not have <code>Expires</code> headers or do not have both <code>Last-Modified</code> 
@@ -149,31 +167,10 @@ and <code>Date</code> headers. To contro
 in the cache, specify an <strong>absolute freshness limit</strong>.</p>
 <h5 id="specifyanabsolutefreshnesslimit">To specify an absolute freshness limit:</h5>
 <ol>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variables:</li>
-<li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><em><code>proxy.config.http.cache.heuristic_min_lifetime</code></em></dt>
-<dd>Set this variable to specify the minimum amount of time that HTTP objects without 
-    an expiration date can remain fresh in the cache before being considered stale. 
-    The default value is 3600 seconds (1 hour).</dd>
-<dt><em><code>proxy.config.http.cache.heuristic_max_lifetime</code></em></dt>
-<dd>Set this variable to specify the maximum amount of time that HTTP objects without 
-    an expiration date can remain fresh in the cache before being considered stale. 
-    The default value is 86400 seconds (1 day).</dd>
-</dl>
-</li>
-<li>
-<p>Save and close the <code>records.config</code> file.</p>
-</li>
-<li>
-<p>Navigate to the Traffic Server <code>bin</code> directory. <br />
-</p>
-</li>
-<li>
-<p>Run the command <code>traffic_line -x</code> to apply the configuration changes. </p>
-</li>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.http.cache.heuristic_min_lifetime"><em><code>proxy.config.http.cache.heuristic_min_lifetime</code></em></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.http.cache.heuristic_max_lifetime"><em><code>proxy.config.http.cache.heuristic_max_lifetime</code></em></a></li>
+<li>Run the <code>traffic_line -x</code> command to apply the configuration changes.</li>
 </ol>
 <h3 id="SpecifyingHeaderRequirements">Specifying Header Requirements</h3>
 <p>To further ensure freshness of the objects in the cache, configure Traffic 
@@ -185,27 +182,9 @@ the cache hit rate will be noticeably re
 have explicit expiration information).</p>
 <h5 id="configureTScacheobjectswithspecificheaders">To configure Traffic Server to cache objects with specific headers:</h5>
 <ol>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variable:</li>
-<li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><code>_proxy.config.http.cache.required_headers_</code></dt>
-<dd />
-</dl>
-<div class="codehilite"><pre><span class="n">Set</span> <span class="n">this</span> <span class="n">variable</span> <span class="n">to</span> <span class="n">one</span> <span class="n">of</span> <span class="n">the</span> <span class="n">following</span> <span class="nb">values</span><span class="p">:</span>  
- <span class="err">  </span><span class="sb">`0`</span> <span class="o">=</span> <span class="nb">no</span> <span class="n">headers</span> <span class="n">required</span> <span class="n">to</span> <span class="n">make</span> <span class="n">document</span> <span class="n">cacheable</span>  
- <span class="err">  </span><span class="sb">`1`</span> <span class="o">=</span> <span class="n">either</span> <span class="n">the</span> <span class="sb">`Last-Modified`</span> <span class="n">header</span><span class="p">,</span> <span class="ow">or</span> <span class="n">an</span> <span class="n">explicit</span> <span class="n">lifetime</span> <span class="n">header</span><span class="p">,</span> <span class="sb">` Expires`</span> <span class="ow">or</span> <span class="sb">` Cache-Control: max-age`</span><span class="p">,</span> <span class="n">is</span> <span class="n">required</span>  
- <span class="err">  </span><span class="sb">`2`</span> <span class="o">=</span> <span class="n">explicit</span> <span class="n">lifetime</span> <span class="n">is</span> <span class="n">required</span><span class="p">,</span> <span class="sb">` Expires`</span> <span class="ow">or</span> <span class="sb">` Cache-Control: max-age`</span>
-</pre></div>
-
-
-</li>
-<li>
-<p>Save and close the <code>records.config</code> file. </p>
-</li>
-<li>Navigate to the Traffic Server <code>bin</code> directory. </li>
-<li>Run the command <code>traffic_line -x</code> to apply the configuration changes. </li>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.http.cache.required_headers"><em><code>proxy.config.http.cache.required_headers</code></em></a></li>
+<li>Run the <code>traffic_line -x</code> command to apply the configuration changes.</li>
 </ol>
 <h3 id="Cache-ControlHeaders">Cache-Control Headers</h3>
 <p>Even though an object might be fresh in the cache, clients or servers often 
@@ -216,10 +195,28 @@ from a cache, or if it does, then it can
 headers that appear in both client requests and server responses. The following 
 <code>Cache-Control</code> headers affect whether objects are served from cache: </p>
 <ul>
-<li>The <code>no-cache</code> header, sent by clients, tells Traffic Server that it should not to serve any objects directly from the cache; therefore, Traffic Server will always obtain the object from the origin server. You can configure Traffic Server to ignore client <code>no-cache</code> headers - refer to <a href="#NoCacheHeaders">Configuring Traffic Server to Ignore Client no-cache Headers</a> for more information.</li>
-<li>The <code>max-age</code> header, sent by servers, is compared to the object age. If the age is less than <code>max-age</code>, then the object is fresh and can be served.</li>
-<li>The <code>min-fresh</code> header, sent by clients, is an <strong>acceptable freshness tolerance</strong>. This means that the client wants the object to be at least this fresh. If a cached object does not remain fresh at least this long in the future, then it is revalidated. </li>
-<li>The <code>max-stale</code> header, sent by clients, permits Traffic Server to serve stale objects provided they are not too old. Some browsers might be willing to take slightly stale objects in exchange for improved performance, especially during periods of poor Internet availability. </li>
+<li>
+<p>The <code>no-cache</code> header, sent by clients, tells Traffic Server that it should
+  not to serve any objects directly from the cache; therefore, Traffic Server will
+  always obtain the object from the origin server. You can configure Traffic Server
+  to ignore client <code>no-cache</code> headers - refer to
+  <a href="#NoCacheHeaders">Configuring Traffic Server to Ignore Client no-cache Headers</a> for more information.</p>
+</li>
+<li>
+<p>The <code>max-age</code> header, sent by servers, is compared to the object age.
+  If the age is less than <code>max-age</code>, then the object is fresh and can be served.</p>
+</li>
+<li>
+<p>The <code>min-fresh</code> header, sent by clients, is an <strong>acceptable freshness tolerance</strong>.
+  This means that the client wants the object to be at least this fresh.
+  If a cached object does not remain fresh at least this long in the future, then it is revalidated. </p>
+</li>
+<li>
+<p>The <code>max-stale</code> header, sent by clients, permits Traffic Server to serve stale
+  objects provided they are not too old. Some browsers might be willing to take
+  slightly stale objects in exchange for improved performance, especially during
+  periods of poor Internet availability. </p>
+</li>
 </ul>
 <p>Traffic Server applies <code>Cache-Control</code> servability criteria after HTTP freshness 
 criteria. For example, an object might be considered fresh but will not be 
@@ -230,10 +227,22 @@ revalidates the object. A <strong>revali
 to check if the object is unchanged. The result of a revalidation is one of 
 the following:</p>
 <ul>
-<li>If the object is still fresh, then Traffic Server resets its freshness limit and serves the object. </li>
-<li>If a new copy of the object is available, then Traffic Server caches the new object (thereby replacing the stale copy) and simultaneously serves the object to the user. </li>
-<li>If the object no longer exists on the origin server, then Traffic Server does not serve the cached copy. </li>
-<li>If the origin server does not respond to the revalidation query, then Traffic Server serves the stale object along with a <code>111 Revalidation Failed</code> warning. </li>
+<li>
+<p>If the object is still fresh, then Traffic Server resets its freshness
+  limit and serves the object. </p>
+</li>
+<li>
+<p>If a new copy of the object is available, then Traffic Server caches the
+  new object (thereby replacing the stale copy) and simultaneously serves the object to the user. </p>
+</li>
+<li>
+<p>If the object no longer exists on the origin server, then Traffic Server
+  does not serve the cached copy. </p>
+</li>
+<li>
+<p>If the origin server does not respond to the revalidation query, then
+  Traffic Server serves the stale object along with a <code>111 Revalidation Failed</code> warning. </p>
+</li>
 </ul>
 <p>By default, Traffic Server revalidates a requested HTTP object in the cache 
 if it considers the object to be stale. Traffic Server evaluates object freshness 
@@ -245,36 +254,12 @@ how Traffic Server evaluates freshness b
 <li>Traffic Server considers all HTTP objects without <code>Expires</code> or <code>Cache-control</code> headers to be stale: revalidate all HTTP objects without <code>Expires</code> or <code>Cache-Control</code> headers. </li>
 </ul>
 <p>To configure how Traffic Server revalidates objects in the cache, you can set 
-specific revalidation rules in the <code>cache.config</code> file (refer to <a href="files.htm#cache.config">cache.config</a>). </p>
+specific revalidation rules in <a href="../configuration-files/records.config"><code>cache.config</code></a>. </p>
 <h5 id="configurerevalidationoptions">To configure revalidation options:</h5>
 <ol>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variable: </li>
-<li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><code>_proxy.config.http.cache.when_to_revalidate_</code></dt>
-<dd />
-</dl>
-<div class="codehilite"><pre><span class="n">Set</span> <span class="n">this</span> <span class="n">variable</span> <span class="n">to</span> <span class="n">one</span> <span class="n">of</span> <span class="n">the</span> <span class="n">following</span> <span class="nb">values</span><span class="p">:</span>  
- <span class="err">  </span><span class="mi">0</span> <span class="o">=</span> <span class="n">Configures</span> <span class="n">Traffic</span> <span class="n">Server</span> <span class="n">to</span> <span class="n">revalidate</span> <span class="n">an</span> <span class="n">HTTP</span> <span class="n">object</span> <span class="n">whenever</span> <span class="n">it</span> <span class="n">is</span> <span class="n">considered</span> <span class="n">stale</span> <span class="n">in</span> <span class="n">the</span> <span class="n">cache</span><span class="o">.</span> <span class="p">(</span><span class="n">Traffic</span> <span class="n">Server</span> <span class="n">checks</span> <span class="n">the</span> <span class="n">headers</span> <span class="ow">and</span> <span class="n">the</span> <span class="n">freshness</span> <span class="n">limit</span><span class="p">,</span> <span class="k">if</span> <span class="n">applicable</span><span class="o">.</span><span class="p"
 >)</span> <span class="n">This</span> <span class="n">is</span> <span class="n">the</span> <span class="n">default</span> <span class="n">option</span><span class="o">.</span>  
- <span class="err">  </span><span class="mi">1</span> <span class="o">=</span> <span class="n">Configures</span> <span class="n">Traffic</span> <span class="n">Server</span> <span class="n">to</span> <span class="n">revalidate</span> <span class="n">HTTP</span> <span class="n">objects</span> <span class="n">that</span> <span class="k">do</span> <span class="ow">not</span> <span class="n">contain</span> <span class="sb">`Expires`</span> <span class="ow">or</span> <span class="sb">`Cache-control`</span> <span class="n">headers</span><span class="o">.</span>  
- <span class="err">  </span><span class="mi">2</span> <span class="o">=</span> <span class="n">Configures</span> <span class="n">Traffic</span> <span class="n">Server</span> <span class="n">to</span> <span class="n">always</span> <span class="n">revalidate</span> <span class="n">HTTP</span> <span class="n">objects</span><span class="p">;</span> <span class="n">Traffic</span> <span class="n">Server</span> <span class="n">always</span> <span class="n">considers</span> <span class="n">HTTP</span> <span class="n">objects</span> <span class="n">to</span> <span class="n">be</span> <span class="n">stale</span><span class="o">.</span>  
- <span class="err">  </span><span class="mi">3</span> <span class="o">=</span> <span class="n">Configures</span> <span class="n">Traffic</span> <span class="n">Server</span> <span class="n">to</span> <span class="n">never</span> <span class="n">revalidate</span> <span class="n">HTTP</span> <span class="n">objects</span><span class="p">;</span> <span class="n">Traffic</span> <span class="n">Server</span> <span class="n">always</span> <span class="n">considers</span> <span class="n">HTTP</span> <span class="n">objects</span> <span class="n">to</span> <span class="n">be</span> <span class="n">fresh</span><span class="o">.</span>
-</pre></div>
-
-
-</li>
-<li>
-<p>Save and close the<code>records.config</code>file. </p>
-</li>
-<li>
-<p>Navigate to the Traffic Server <code>bin</code> directory. <br />
-</p>
-</li>
-<li>
-<p>Run the command <code>traffic_line -x</code> to apply the configuration changes.</p>
-</li>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.http.cache.when_to_revalidate"><em><code>proxy.config.http.cache.when_to_revalidate</code></em></a></li>
+<li>Run the <code>traffic_line -x</code> command to apply the configuration changes.</li>
 </ol>
 <h2 id="SchedulingUpdatesLocalCacheContent">Scheduling Updates to Local Cache Content</h2>
 <p>To further increase performance and to ensure that HTTP objects are fresh in 
@@ -284,8 +269,13 @@ find this especially beneficial when usi
 so you can preload content you anticipate will be in demand. </p>
 <p>To use the Scheduled Update option, you must perform the following tasks. </p>
 <ul>
-<li>Specify the list of URLs that contain the objects you want to schedule for update, the time the update should take place, and the recursion depth for the URL.</li>
-<li>Enable the scheduled update option and configure optional retry settings.</li>
+<li>
+<p>Specify the list of URLs that contain the objects you want to schedule
+  for update, the time the update should take place, and the recursion depth for the URL.</p>
+</li>
+<li>
+<p>Enable the scheduled update option and configure optional retry settings.</p>
+</li>
 </ul>
 <p>Traffic Server uses the information you specify to determine URLs for which 
 it is responsible. For each URL, Traffic Server derives all recursive URLs 
@@ -299,123 +289,75 @@ you to update URLs immediately without w
 to occur. You can use this option to test your scheduled update configuration 
 (refer to <a href="#ForcingImmediateUpdate">Forcing an Immediate Update</a>). </p>
 <h3 id="ConfiguringScheduledUpdateOption">Configuring the Scheduled Update Option</h3>
-<h5 id="to_configure_the_scheduled_update_option_follow_the_steps_below__configurescheduledupdateoptionfollowstepsbelow">To configure the scheduled update option, follow the steps below: ##### {#configurescheduledupdateoption,followstepsbelow}</h5>
+<h5 id="configurescheduledupdateoption">To configure the scheduled update option:</h5>
 <ol>
-<li>In a text editor, open the <code>update.config file</code> located in the Traffic Server <code>config</code> directory. </li>
-<li>Enter a line in the file for each URL you want to update (refer to <a href="files.htm#update.config">update.config</a>). </li>
-<li>Save and close the <code>update.config</code> file.</li>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variables:</li>
-<li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><code>_proxy.config.update.enabled_</code></dt>
-<dd>Set this variable to 1 to enable the scheduled update option.</dd>
-<dt><code>_proxy.config.update.retry_count_</code></dt>
-<dd>Set this variable to specify the number of times you want to retry the scheduled 
-    update of a URL in the event of failure. The default value is 10.</dd>
-<dt><code>_proxy.config.update.retry_interval_</code></dt>
-<dd>Set this variable to specify the delay in seconds between each scheduled update 
-    retry for a URL in the event of failure. The default value is 2.</dd>
-<dt><code>_proxy.config.update.concurrent_updates_</code></dt>
-<dd>Set this variable to specify the maximum simultaneous update requests allowed 
-    at any point in time. This option prevents the scheduled update process from 
-    overburdening the host. The default value is 100.</dd>
-</dl>
-</li>
-<li>
-<p>Save and close the <code>records.config</code> file.</p>
-</li>
-<li>
-<p>Navigate to the Traffic Server <code>bin</code> directory. <br />
-</p>
-</li>
-<li>
-<p>Run the command <code>traffic_line -x</code> to apply the configuration changes. </p>
-</li>
+<li>In <a href="../configuration-files/update.config"><code>update.config</code></a> enter a line in the file for each URL you want to update.</li>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.http.update.enabled"><em><code>proxy.config.update.enabled</code></em></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.http.update.retry_count"><em><code>proxy.config.update.retry_count</code></em></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.http.update.retry_interval"><em><code>proxy.config.update.retry_interval</code></em></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.http.update.concurrent_updates"><em><code>proxy.config.update.concurrent_updates</code></em></a></li>
+<li>Run the <code>traffic_line -x</code> command to apply the configuration changes.</li>
 </ol>
-<h3 id="ForcinganImmediateUpdate">Forcing an Immediate Update</h3>
+<h3 id="ForcingImmediateUpdate">Forcing an Immediate Update</h3>
 <p>Traffic Server provides a <strong>Force Immediate Update</strong> option that enables you 
 to immediately verify the URLs listed in the <code>update.config</code> file. The Force 
 Immediate Update option disregards the offset hour and interval set in the 
 <code>update.config</code> file and immediately updates the URLs listed. </p>
-<p>To configure the Force Immediate Update option, follow the steps below:</p>
+<h5 id="configureForceImmediateUpdateoption">To configure the Force Immediate Update option:</h5>
 <ol>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variable:</li>
-<li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><code>_proxy.config.update.force_</code></dt>
-<dd />
-</dl>
-<div class="codehilite"><pre><span class="n">Set</span> <span class="n">this</span> <span class="n">variable</span> <span class="n">to</span> <span class="mi">1</span> <span class="n">to</span> <span class="n">enable</span> <span class="n">the</span> <span class="n">Force</span> <span class="n">Immediate</span> <span class="n">Update</span> <span class="n">option</span><span class="o">.</span>
-</pre></div>
-
-
-</li>
-<li>
-<p>Make sure that the variable <code>_proxy.config.update.enabled_</code> is set to 1. </p>
-</li>
-<li>Save and close the <code>records.config</code> file. </li>
-<li>
-<p>Navigate to the Traffic Server <code>bin</code> directory.<br />
-</p>
-</li>
-<li>
-<p>Run the <code>command traffic_line -x</code> to apply the configuration changes. </p>
-</li>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.http.update.force"><em><code>proxy.config.update.force</code></em></a></li>
+<li>Make sure the variable <a href="../configuration-files/records.config#proxy.config.http.update.enabled"><em><code>proxy.config.update.enabled</code></em></a> is set to 1.</li>
+<li>Run the <code>command traffic_line -x</code> to apply the configuration changes. </li>
 </ol>
-<p><strong>IMPORTANT: </strong>When you enable the Force Immediate Update option, Traffic Server 
+<p><strong>IMPORTANT:</strong> When you enable the Force Immediate Update option, Traffic Server 
 continually updates the URLs specified in the <code>update.config</code> file until you 
 disable the option. To disable the Force Immediate Update option, set the variable 
-<code>_proxy.config.update.force_</code> to <code>0</code> (zero).</p>
+<a href="../configuration-files/records.config#proxy.config.http.update.force"><em><code>proxy.config.update.force</code></em></a> to <code>0</code> (zero).</p>
 <h2 id="PushingContentintoCache">Pushing Content into the Cache</h2>
 <p>Traffic Server supports the HTTP <code>PUSH</code> method of content delivery. Using HTTP 
 <code>PUSH</code>, you can deliver content directly into the cache without user requests. </p>
 <h3 id="ConfiguringTSAcceptPUSHRequests">Configuring Traffic Server to Accept PUSH Requests</h3>
 <p>Before you can deliver content into your cache using HTTP <code>PUSH</code>, you must 
 configure Traffic Server to accept <code>PUSH</code> requests.</p>
-<h5 id="to_configure_traffic_server_to_accept_push_requests___configuretsacceptpushrequests">To configure Traffic Server to accept <code>PUSH</code> requests:  ##### {#configureTSaccept<code>PUSH</code>requests}</h5>
+<h5 id="configureTSacceptPUSHrequests">To configure Traffic Server to accept <code>PUSH</code> requests:</h5>
 <ol>
-<li>In a text editor, open the <code>filter.config</code> file located in the Traffic Server config directory. </li>
-<li>Add the following filter rules to the file to ensure that only certain IP addresses can deliver <code>PUSH</code> requests to the cache: <br />
-<code>domain=. src_ip=_ipaddress_ method=PUSH action=allow   
-domain=. method=PUSH action=deny</code> <br />
- where <code>_ipaddress_</code> is the IP address of the host or range of IP addresses of the hosts from which Traffic Server accepts PUSH requests. </li>
-<li>Save and close the <code>filter.config</code> file. </li>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variable:</li>
-<li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><code>_proxy.config.http.push_method_enabled_</code></dt>
-<dd />
-</dl>
-<div class="codehilite"><pre><span class="n">Set</span> <span class="n">this</span> <span class="n">variable</span> <span class="n">to</span> <span class="mi">1</span> <span class="n">to</span> <span class="n">enable</span> <span class="n">Traffic</span> <span class="n">Server</span> <span class="n">to</span> <span class="nb">accept</span> <span class="n">PUSH</span> <span class="n">requests</span><span class="o">.</span>
+<li>In <a href="../configuration-files/filter.config"><code>filter.config</code></a></li>
+<li>
+<p>Add the following filter rules to the file to ensure that only certain IP addresses can deliver <code>PUSH</code> requests to the cache:</p>
+<div class="codehilite"><pre>domain=. src_ip=ipaddress method=PUSH action=allow
+domain=. method=PUSH action=deny
 </pre></div>
 
 
+<p>where <em><code>ipaddress</code></em> is the IP address of the host or range of IP addresses of the hosts from
+   which Traffic Server accepts <code>PUSH</code> requests. </p>
 </li>
 <li>
-<p>Save and close the <code>records.config</code> file. </p>
+<p>In <a href="../configuration-files/records.config"><code>records.config</code></a></p>
 </li>
-<li>Navigate to the Traffic Server <code>bin</code> directory. </li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.http.push_method_enabled"><em><code>proxy.config.http.push_method_enabled</code></em></a></li>
 <li>Run the command <code>traffic_line -x</code> to apply the configuration changes. </li>
 </ol>
 <h3 id="UnderstandingHTTPPUSH">Understanding HTTP PUSH</h3>
 <p><code>PUSH</code> uses the HTTP 1.1 message format. The body of a <code>PUSH</code> request contains 
 the response header and response body that you want to place in the cache. 
 The following is an example of a <code>PUSH</code> request: </p>
-<p><code>PUSH http://www.company.com HTTP/1.0   
-Content-length: 84</code></p>
-<p><code>HTTP/1.0 200 OK   
-Content-type: text/html   
-Content-length: 17</code></p>
-<p><code>&lt;HTML&gt;   
-a   
-&lt;/HTML&gt;</code></p>
-<p><strong>IMPORTANT: </strong>Your header must include <code>Content-length</code>; <code>Content-length</code> 
+<div class="codehilite"><pre>PUSH http://www.company.com HTTP/1.0
+Content-length: 84
+
+HTTP/1.0 200 OK
+Content-type: text/html
+Content-length: 17
+
+<span class="nt">&lt;HTML&gt;</span>
+a
+<span class="nt">&lt;/HTML&gt;</span>
+</pre></div>
+
+
+<p><strong>IMPORTANT:</strong> Your header must include <code>Content-length</code>; <code>Content-length</code> 
 must include both <code>header</code> and <code>body byte count</code>.</p>
 <h2 id="PinningContentinCache">Pinning Content in the Cache</h2>
 <p>The <strong>Cache Pinning Option</strong> configures Traffic Server to keep certain HTTP 
@@ -425,33 +367,24 @@ Server from deleting important objects. 
 headers and pins an object in the cache only if it is indeed cacheable.</p>
 <h5 id="setcachepinningrulesenableCachePinning">To set cache pinning rules and enable Cache Pinning:</h5>
 <ol>
-<li>In a text editor, open the <code>cache.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Add a rule in the file for each URL you want Traffic Server to pin in the cache, as shown below. <br />
-<code>url_regex=_URL_ pin-in-cache=12h</code> <br />
- where <code>_URL_</code> is the URL you want Traffic Server to pin in the cache. The time format can be <code>d</code> for days, <code>h</code> for hours (as shown), <code>m</code> for minutes, and <code>s</code> for seconds. You can also use mixed units: for example, <code>1h15m20s</code>. You can add secondary specifiers (such as prefix and suffix) to the rule (refer to <a href="files.htm#cache.config">cache.config</a> for more information). </li>
-<li>Save and close the <code>cache.config</code> file. </li>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variable:</li>
-<li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><code>_proxy.config.cache.permit.pinning_</code></dt>
-<dd />
-</dl>
-<div class="codehilite"><pre><span class="n">Set</span> <span class="n">this</span> <span class="n">variable</span> <span class="n">to</span> <span class="mi">1</span> <span class="n">to</span> <span class="n">enable</span> <span class="n">the</span> <span class="n">cache</span> <span class="n">pinning</span> <span class="n">option</span><span class="o">.</span>
+<li>In <a href="../configuration-files/cache.config"><code>cache.config</code></a></li>
+<li>
+<p>Add a rule in the file for each URL you want Traffic Server to pin in the cache, as shown below.</p>
+<div class="codehilite"><pre><span class="n">url_regex</span><span class="o">=</span><span class="n">URL</span> <span class="n">pin</span><span class="o">-</span><span class="n">in</span><span class="o">-</span><span class="n">cache</span><span class="o">=</span><span class="mi">12</span><span class="n">h</span>
 </pre></div>
 
 
+<p>where <em><code>URL</code></em> is the URL you want Traffic Server to pin in the cache. The time format can be <code>d</code> for days,
+   <code>h</code> for hours (as shown), <code>m</code> for minutes, and <code>s</code> for seconds. You can also use mixed units:
+   for example, <code>1h15m20s</code>. You can add secondary specifiers (such as prefix and suffix) to the rule.</p>
 </li>
 <li>
-<p>Navigate to the Traffic Server <code>bin</code> directory.<br />
-</p>
-</li>
-<li>
-<p>Run the command <code>traffic_line -x</code> to apply the configuration changes. </p>
+<p>In <a href="../configuration-files/records.config"><code>records.config</code></a></p>
 </li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.cache.permit.pinning"><em><code>proxy.config.cache.permit.pinning</code></em></a></li>
+<li>Run the command <code>traffic_line -x</code> to apply the configuration changes. </li>
 </ol>
-<h2 id="to_cache_or_not_to_cache__cachenotcache">To Cache or Not to Cache? ## {#CacheNotCache?}</h2>
+<h2 id="CacheNotCache">To Cache or Not to Cache?</h2>
 <p>When Traffic Server receives a request for a web object that is not in the 
 cache, it retrieves the object from the origin server and serves it to the 
 client. At the same time, Traffic Server checks if the object is cacheable 
@@ -464,59 +397,60 @@ as well as directives you specify throug
 <strong>headers</strong>: </p>
 <ul>
 <li><code>Cache-Control: no-store</code> header </li>
-<li><code>Cache-Control: no-cache</code> header <br />
- To configure Traffic Server to ignore the <code>Cache-Control: no-cache</code> header, refer to <a href="#NoCacheHeaders">Configuring Traffic Server to Ignore Client no-cache Headers</a>. </li>
-<li><code>Cookie</code>: header (for text objects) <br />
- By default, Traffic Server caches objects served in response to requests that contain cookies (unless the object is text). You can configure Traffic Server to not cache cookied content of any type, cache all cookied content, or cache cookied content that is of image type only. For more information, refer to <a href="#CachingCookiedObjects">Caching Cookied Objects</a>.</li>
-<li><code>Authorization</code>: header </li>
+<li>
+<p><code>Cache-Control: no-cache</code> header</p>
+<p>To configure Traffic Server to ignore the <code>Cache-Control: no-cache</code> header,
+refer to <a href="#NoCacheHeaders">Configuring Traffic Server to Ignore Client no-cache Headers</a>. </p>
+</li>
+<li>
+<p><code>Cookie</code>: header (for text objects) </p>
+<p>By default, Traffic Server caches objects served in response to requests that
+contain cookies (unless the object is text). You can configure Traffic Server
+to not cache cookied content of any type, cache all cookied content, or cache
+cookied content that is of image type only. For more information,
+refer to <a href="#CachingCookiedObjects">Caching Cookied Objects</a>.</p>
+</li>
+<li>
+<p><code>Authorization</code>: header </p>
+</li>
 </ul>
-<h4 id="ConfiguringTSIgnoreClientno-cacheHeaders">Configuring Traffic Server to Ignore Client no-cache Headers</h4>
-<p>By default, Traffic Server strictly observes client <code>Cache Control:no-cache</code> 
+<h4 id="ConfiguringTSIgnoreClientnocacheHeaders">Configuring Traffic Server to Ignore Client no-cache Headers</h4>
+<p>By default, Traffic Server strictly observes client <code>Cache-Control: no-cache</code> 
 directives. If a requested object contains a <code>no-cache</code> header, then Traffic 
 Server forwards the request to the origin server even if it has a fresh copy 
 in cache. You can configure Traffic Server to ignore client <code>no-cache</code> directives 
 such that it ignores <code>no-cache</code> headers from client requests and serves the 
 object from its cache. </p>
-<h5 id="to_configure_traffic_server_to_ignore_client_no-cache_headers___configuretsignoreclientno-cacheheaders">To configure Traffic Server to ignore client <code>no-cache</code> headers:  ##### {#configureTSignoreclient<code>no-cache</code>headers}</h5>
+<h5 id="configureTSignoreclientnocacheheaders">To configure Traffic Server to ignore client <code>no-cache</code> headers:</h5>
 <ol>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variable:</li>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.cache.ignore_client_no_cache"><em><code>proxy.config.cache.ignore_client_no_cache</code></em></a></li>
+<li>Run the command <code>traffic_line -x</code> to apply the configuration changes. </li>
+</ol>
+<h3 id="OriginServerDirectives">Origin Server Directives</h3>
+<p>By default, Traffic Server does <em>not</em> cache objects with the following <strong>response</strong> 
+<strong>headers</strong>: </p>
+<ul>
+<li><code>Cache-Control: no-store</code> header </li>
+<li><code>Cache-Control: private</code> header </li>
 <li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><code>_proxy.config.http.cache.ignore_client_no_cache_</code></dt>
-<dd />
-</dl>
-<div class="codehilite"><pre><span class="n">Set</span> <span class="n">this</span> <span class="n">variable</span> <span class="n">to</span> <span class="mi">1</span> <span class="n">to</span> <span class="n">ignore</span> <span class="n">client</span> <span class="n">requests</span> <span class="n">to</span> <span class="n">bypass</span> <span class="n">the</span> <span class="n">cache</span><span class="o">.</span>
-</pre></div>
-
-
+<p><code>WWW-Authenticate</code>: header</p>
+<p>To configure Traffic Server to ignore<code>WWW-Authenticate</code> headers,
+ refer to <a href="#ConfiguringTrafficEdgeIgnoreWWWAuthenticateHeaders">Configuring Traffic Server to Ignore WWW-Authenticate Headers</a>. </p>
 </li>
 <li>
-<p>Save and close the <code>records.config</code> file. </p>
+<p><code>Set-Cookie</code>: header </p>
 </li>
 <li>
-<p>Navigate to the Traffic Server <code>bin</code> directory. <br />
-</p>
+<p><code>Cache-Control: no-cache</code> headers</p>
+<p>To configure Traffic Server to ignore <code>no-cache</code> headers,
+ refer to <a href="#ConfiguringTrafficEdgeIgnoreServerNoCacheHeaders">Configuring Traffic Server to Ignore Server no-cache Headers</a>. </p>
 </li>
 <li>
-<p>Run the command <code>traffic_line -x</code> to apply the configuration changes. </p>
+<p><code>Expires</code>: header with value of 0 (zero) or a past date </p>
 </li>
-</ol>
-<h3 id="OriginServerDirectives">Origin Server Directives</h3>
-<p>By default, Traffic Server does <em>not</em> cache objects with the following <strong>response</strong> 
-<strong>headers</strong>: </p>
-<ul>
-<li><code>Cache-Control: no-store</code> header </li>
-<li><code>Cache-Control: private</code> header </li>
-<li><code>WWW-Authenticate</code>: header <br />
- To configure Traffic Server to ignore<code>WWW-Authenticate</code> headers, refer to <a href="#ConfiguringTrafficEdgeIgnoreWWWAuthenticateHeaders">Configuring Traffic Server to Ignore WWW-Authenticate Headers</a>. </li>
-<li><code>Set-Cookie</code>: header </li>
-<li><code>Cache-Control: no-cache</code> headers <br />
- To configure Traffic Server to ignore <code>no-cache</code> headers, refer to <a href="#ConfiguringTrafficEdgeIgnoreServerNoCacheHeaders">Configuring Traffic Server to Ignore Server no-cache Headers</a>. </li>
-<li><code>Expires</code>: header with value of 0 (zero) or a past date </li>
 </ul>
-<h4 id="configuring_traffic_server_to_ignore_server_no-cache_headers___configuringtsignoreserverno-cacheheaders">Configuring Traffic Server to Ignore Server <strong>no-cache</strong> Headers  #### {#ConfiguringTSIgnoreServer<strong>no-cache</strong>Headers}</h4>
+<h4 id="ConfiguringTSIgnoreServernocacheHeaders">Configuring Traffic Server to Ignore Server <strong>no-cache</strong> Headers</h4>
 <p>By default, Traffic Server strictly observes <code>Cache-Control:no-cache</code> directives. 
 A response from an origin server with a <code>no-cache</code> header is not stored in 
 the cache and any previous copy of the object in the cache is removed. If you 
@@ -525,31 +459,11 @@ also ignores <code>no-store</code> heade
 directives is appropriate in most cases. </p>
 <h5 id="to_configure_traffic_server_to_ignore_server_no-cache_headers___configuretsignoreserverno-cacheheaders">To configure Traffic Server to ignore server <code>no-cache</code> headers:  ##### {#configureTSignoreserver<code>no-cache</code>headers}</h5>
 <ol>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variable:</li>
-<li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><code>_proxy.config.http.cache.ignore_server_no_cache_</code></dt>
-<dd />
-</dl>
-<div class="codehilite"><pre><span class="n">Set</span> <span class="n">this</span> <span class="n">variable</span> <span class="n">to</span> <span class="mi">1</span> <span class="n">to</span> <span class="n">ignore</span> <span class="n">server</span> <span class="n">directives</span> <span class="n">to</span> <span class="n">bypass</span> <span class="n">the</span> <span class="n">cache</span><span class="o">.</span>
-</pre></div>
-
-
-</li>
-<li>
-<p>Save and close the <code>records.config</code> file. </p>
-</li>
-<li>
-<p>Navigate to the Traffic Server <code>bin</code> directory. <br />
-</p>
-</li>
-<li>
-<p>Run the command <code>traffic_line -x</code> to apply the configuration changes. </p>
-</li>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.cache.ignore_server_no_cache"><em><code>proxy.config.cache.ignore_server_no_cache</code></em></a></li>
+<li>Run the command <code>traffic_line -x</code> to apply the configuration changes. </li>
 </ol>
-<h4 id="ConfiguringTSIgnoreWWW-AuthenticateHeaders">Configuring Traffic Server to Ignore WWW-Authenticate Headers</h4>
+<h4 id="ConfiguringTSIgnoreWWWAuthenticateHeaders">Configuring Traffic Server to Ignore WWW-Authenticate Headers</h4>
 <p>By default, Traffic Server does not cache objects that contain <code>WWW-Authenticate</code> 
 response headers. The <code>WWW-Authenticate</code> header contains authentication parameters 
 the client uses when preparing the authentication challenge response to an 
@@ -560,35 +474,22 @@ for future requests. However, the defaul
 <code>WWW-Authenticate</code> headers is appropriate in most cases. Only configure Traffic 
 Server to ignore server <code>WWW-Authenticate</code> headers if you are knowledgeable 
 about HTTP 1.1.</p>
-<h5 id="to_configure_traffic_server_to_ignore_server_www-authenticate_headers___configuretsignoreserverwww-authenticateheaders">To configure Traffic Server to ignore server <code>WWW-Authenticate</code> headers:  ##### {#configureTSignoreserver<code>WWW-Authenticate</code>headers}</h5>
+<h5 id="configureTSignoreserverWWWAuthenticateheaders">To configure Traffic Server to ignore server <code>WWW-Authenticate</code> headers:</h5>
 <ol>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variable:</li>
-<li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><code>_proxy.config.http.cache.ignore_authentication_</code></dt>
-<dd />
-</dl>
-<div class="codehilite"><pre><span class="n">Set</span> <span class="n">this</span> <span class="n">variable</span> <span class="n">to</span> <span class="mi">1</span> <span class="n">to</span> <span class="n">cache</span> <span class="n">objects</span> <span class="n">with</span> <span class="n">WWW</span> <span class="n">Authenticate</span> <span class="n">headers</span><span class="o">.</span>
-</pre></div>
-
-
-</li>
-<li>
-<p>Save and close the <code>records.config</code> file. </p>
-</li>
-<li>Navigate to the Traffic Server <code>bin</code> directory. </li>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.cache.ignore_authentication"><em><code>proxy.config.cache.ignore_authentication</code></em></a></li>
 <li>Run the command <code>traffic_line -x</code> to apply the configuration changes. </li>
 </ol>
 <h3 id="ConfigurationDirectives">Configuration Directives</h3>
-<p>In addition to client and origin server directives, Traffic Server responds to directives you specify through configuration options and files. <br />
- You can configure Traffic Server to do the following: </p>
+<p>In addition to client and origin server directives, Traffic Server responds to directives
+you specify through configuration options and files.</p>
+<p>You can configure Traffic Server to do the following: </p>
 <ul>
-<li>_Not _cache any HTTP objects (refer to <a href="#DisablingHTTPObjectCaching">Disabling HTTP Object Caching</a>).</li>
-<li>Cache <strong>dynamic content</strong> - that is, objects with URLs that end in <code>**.asp**</code> or contain a question mark (<strong><code>?</code></strong>), semicolon (<code>**;**</code>), or <code>**cgi**</code>. For more information, refer to <a href="#CachingDynamicContent">Caching Dynamic Content</a>. </li>
+<li><em>Not</em> cache any HTTP objects (refer to <a href="#DisablingHTTPObjectCaching">Disabling HTTP Object Caching</a>).</li>
+<li>Cache <strong>dynamic content</strong> - that is, objects with URLs that end in <strong><code>.asp</code></strong> or contain a question mark (<strong><code>?</code></strong>),
+  semicolon (<strong><code>;</code></strong>), or <strong><code>cgi</code></strong>. For more information, refer to <a href="#CachingDynamicContent">Caching Dynamic Content</a>. </li>
 <li>Cache objects served in response to the <code>Cookie:</code> header (refer to <a href="#CachingCookiedObjects">Caching Cookied Objects)</a>. </li>
-<li>Observe never-cache rules in the <code>cache.config</code> file (refer to <a href="files.htm#cache.config">cache.config</a>).</li>
+<li>Observe never-cache rules in the <code>cache.config</code> file (refer to <a href="../configuration-files/records.config"><code>records.config</code></a>).</li>
 </ul>
 <h4 id="DisablingHTTPObjectCaching">Disabling HTTP Object Caching</h4>
 <p>By default, Traffic Server caches all HTTP objects except those for which you 
@@ -597,50 +498,19 @@ object caching so that all HTTP objects 
 server and never cached, as detailed below.</p>
 <h5 id="disableHTTPobjectcachingmanually">To disable HTTP object caching manually:</h5>
 <ol>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variable:</li>
-<li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><code>_proxy.config.http.cache.http_</code></dt>
-<dd />
-</dl>
-<div class="codehilite"><pre><span class="n">Set</span> <span class="n">this</span> <span class="n">variable</span> <span class="n">to</span> <span class="mi">0</span> <span class="p">(</span><span class="n">zero</span><span class="p">)</span> <span class="n">to</span> <span class="n">disable</span> <span class="n">HTTP</span> <span class="n">object</span> <span class="n">caching</span><span class="o">.</span>
-</pre></div>
-
-
-</li>
-<li>
-<p>Save and close the <code>records.config</code> file. </p>
-</li>
-<li>Navigate to the Traffic Server <code>bin</code> directory. </li>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.cache.http"><em><code>proxy.config.cache.http</code></em></a></li>
 <li>Run the command <code>traffic_line -x</code> to apply the configuration changes.</li>
 </ol>
 <h4 id="CachingDynamicContent">Caching Dynamic Content</h4>
-<p>A URL is considered <strong>dynamic</strong> if it ends in <code>**.asp**</code> or contains a question 
-mark (<strong><code>?</code></strong>), a semicolon (<strong><code>;</code></strong>), or <code>**cgi**</code>. By default, Traffic Server 
+<p>A URL is considered <strong>dynamic</strong> if it ends in <strong><code>.asp</code></strong> or contains a question 
+mark (<strong><code>?</code></strong>), a semicolon (<strong><code>;</code></strong>), or <strong><code>cgi</code></strong>. By default, Traffic Server 
 does <em>not</em> cache dynamic content. You can configure Traffic Server to cache 
-dynamic content, although it's recommended for specialized proxy situations 
-only.</p>
+dynamic content, although it's recommended for specialized proxy situations only.</p>
 <h5 id="configureTScachedynamiccontent">To configure Traffic Server to cache dynamic content:</h5>
 <ol>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variable:</li>
-<li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><code>_proxy.config.http.cache_urls_that_look_dynamic_</code></dt>
-<dd />
-</dl>
-<div class="codehilite"><pre><span class="n">Set</span> <span class="n">this</span> <span class="n">variable</span> <span class="n">to</span> <span class="mi">1</span> <span class="n">to</span> <span class="n">cache</span> <span class="n">dynamic</span> <span class="n">content</span><span class="o">.</span>
-</pre></div>
-
-
-</li>
-<li>
-<p>Save and close the <code>records.config</code> file. </p>
-</li>
-<li>Navigate to the Traffic Server <code>bin</code> directory.</li>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.cache_urls_that_look_dynamic"><em><code>proxy.config.cache_urls_that_look_dynamic</code></em></a></li>
 <li>Run the command <code>traffic_line -x</code> to apply the configuration changes.</li>
 </ol>
 <h4 id="CachingCookiedObjects">Caching Cookied Objects</h4>
@@ -652,33 +522,14 @@ non-text objects, it is unlikely that pe
 used. </p>
 <p>You can reconfigure Traffic Server to: </p>
 <ul>
-<li>_Not _ cache cookied content of any type. </li>
+<li><em>Not</em> cache cookied content of any type. </li>
 <li>Cache cookied content that is of image type only. </li>
 <li>Cache all cookied content regardless of type.</li>
 </ul>
 <h5 id="configurehowTScachescookiedcontent">To configure how Traffic Server caches cookied content:</h5>
 <ol>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variable:</li>
-<li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><code>_proxy.config.http.cache.cache_responses_to_cookies_</code></dt>
-<dd />
-</dl>
-<div class="codehilite"><pre><span class="n">Set</span> <span class="n">this</span> <span class="n">variable</span> <span class="n">to</span> <span class="n">specify</span> <span class="n">how</span> <span class="n">Traffic</span> <span class="n">Server</span> <span class="n">caches</span> <span class="n">cookied</span> <span class="n">content:</span>   
- <span class="err">  </span><span class="mi">0</span> <span class="o">=</span> <span class="n">Do</span> <span class="ow">not</span> <span class="n">cache</span> <span class="n">any</span> <span class="n">responses</span> <span class="n">to</span> <span class="n">cookies</span><span class="o">.</span>   
- <span class="err">  </span><span class="mi">1</span> <span class="o">=</span> <span class="n">Cache</span> <span class="n">all</span> <span class="n">responses</span> <span class="n">to</span> <span class="n">cookies</span><span class="o">.</span>   
- <span class="err">  </span><span class="mi">2</span> <span class="o">=</span> <span class="n">Cache</span> <span class="n">responses</span> <span class="n">to</span> <span class="n">cookies</span> <span class="n">of</span> <span class="n">image</span> <span class="n">type</span> <span class="n">only</span><span class="o">.</span>   
- <span class="err">  </span><span class="mi">3</span> <span class="o">=</span> <span class="n">Cache</span> <span class="n">all</span> <span class="n">responses</span> <span class="n">to</span> <span class="n">cookies</span> <span class="n">except</span> <span class="n">text</span> <span class="n">content</span><span class="o">-</span><span class="n">types</span> <span class="p">(</span><span class="n">the</span> <span class="n">default</span><span class="p">)</span><span class="o">.</span>
-</pre></div>
-
-
-</li>
-<li>
-<p>Save and close the <code>records.config</code> file. </p>
-</li>
-<li>Navigate to the Traffic Server <code>bin</code> directory. </li>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>edit <a href="../configuration-files/records.config#proxy.config.cache_responses_to_cookies"><em><code>proxy.config.cache_responses_to_cookies</code></em></a></li>
 <li>Run the command <code>traffic_line -x</code> to apply the configuration changes. </li>
 </ol>
 <h2 id="ForcingObjectCaching">Forcing Object Caching</h2>
@@ -686,13 +537,17 @@ used. </p>
 for a specified duration, regardless of <code>Cache-Control</code> response headers. </p>
 <h5 id="forcedocumentcaching">To force document caching:</h5>
 <ol>
-<li>In a text editor, open the <code>cache.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Add a rule in the file for each URL you want Traffic Server to force cache, as shown below. <br />
-<code>url_regex=_URL_ ttl-in-cache=6h</code> <br />
- where<code>_ URL_</code> is the URL you want Traffic Server to force cache. The time format can be <code>d</code> for days, <code>h</code> for hours (as shown), <code>m</code> for minutes, and <code>s</code> for seconds. You can also use mixed units: for example, <code>1h15m20s</code>. In addition, you can add secondary specifiers (for example, prefix and suffix) to the rule (refer to <a href="files.htm#cache.config">cache.config</a>). </li>
-<li>Save and close the <code>cache.config</code> file. </li>
-<li>Navigate to the Traffic Server <code>bin</code> directory. </li>
-<li>Run the command <code>traffic_line -x</code> to apply the configuration changes. </li>
+<li>In <a href="../configuration-files/cache.config"><code>cache.config</code></a></li>
+<li>
+<p>Add a rule in the file for each URL you want Traffic Server to pin in the cache, as shown below.</p>
+<div class="codehilite"><pre><span class="n">url_regex</span><span class="o">=</span><span class="n">URL</span> <span class="n">ttl</span><span class="o">-</span><span class="n">in</span><span class="o">-</span><span class="n">cache</span><span class="o">=</span><span class="mi">6</span><span class="n">h</span>
+</pre></div>
+
+
+</li>
+<li>
+<p>Run the command <code>traffic_line -x</code> to apply the configuration changes. </p>
+</li>
 </ol>
 <h2 id="CachingHTTPAlternates">Caching HTTP Alternates</h2>
 <p>Some origin servers answer requests to the same URL with a variety of objects. 
@@ -705,41 +560,30 @@ and response headers for specific conten
 as alternates for caching. You can also limit the number of alternate versions 
 of an object allowed in the cache. </p>
 <h3 id="ConfiguringHowTSCachesAlternates">Configuring How Traffic Server Caches Alternates</h3>
-<h5 id="to_configure_how_traffic_server_caches_alternates_follow_the_steps_below___configurehowtscachesalternatesfollowstepsbelow">To configure how Traffic Server caches alternates, follow the steps below:  ##### {#configurehowTScachesalternates,followstepsbelow}</h5>
+<h5 id="configurehowTScachesalternates">To configure how Traffic Server caches alternates, follow the steps below:</h5>
 <ol>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variables:</li>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>set <a href="../configuration-files/records.config#proxy.config.cache.enable_default_vary_headers"><em><code>proxy.config.cache.enable_default_vary_headers</code></em></a> to <code>1</code>
+   to cache alternate versions of HTTP objects that do not contain the Vary header.</li>
+<li>set <a href="../configuration-files/records.config#proxy.config.cache.vary_default_text"><em><code>proxy.config.cache.vary_default_text</code></em></a> to to specify the HTTP
+   header field on which you want to vary if the request is for text: for example, an HTML document.</li>
+<li>set <a href="../configuration-files/records.config#proxy.config.cache.vary_default_images"><em><code>proxy.config.cache.vary_default_images</code></em></a> to to specify the HTTP
+   header field on which you want to vary if the request is for images: for example, a <code>.gif</code> file.</li>
+<li>
+<p>set <a href="../configuration-files/records.config#proxy.config.cache.vary_default_other"><em><code>proxy.config.cache.vary_default_other</code></em></a> to to specify the HTTP
+   header field on which you want to vary  if the request is for anything other than text or image.</p>
+</li>
+<li>
+<p><strong>Note:</strong> If you specify <code>Cookie</code> as the header field on which to vary in the above variables,
+   then make sure that the variable <a href="../configuration-files/records.config#proxy.config.cache.cache_responses_to_cookies"><em><code>proxy.config.cache.cache_responses_to_cookies</code></em></a> is set appropriately.</p>
+<p>For example, if you set <a href="../configuration-files/records.config#proxy.config.cache.cache_responses_to_cookies"><em><code>proxy.config.cache.cache_responses_to_cookies</code></em></a> to
+2 (cache responses to cookies of image type only) and set the <a href="../configuration-files/records.config#proxy.config.cache.vary_default_text"><em><code>proxy.config.cache.vary_default_text</code></em></a>
+variable to specify cookie, then alternates by cookie will not apply to text. </p>
+</li>
 <li>
-<dl>
-<dt><strong>Variable</strong> <strong>Description</strong></dt>
-<dt><code>_proxy.config.http.cache.enable_default_vary_headers_</code></dt>
-<dd />
-</dl>
-<div class="codehilite"><pre><span class="n">Set</span> <span class="n">this</span> <span class="n">variable</span> <span class="n">to</span> <span class="mi">1</span> <span class="n">to</span> <span class="n">cache</span> <span class="n">alternate</span> <span class="n">versions</span> <span class="n">of</span> <span class="n">HTTP</span> <span class="n">objects</span> <span class="n">that</span> <span class="k">do</span> 
-<span class="ow">not</span> <span class="n">contain</span> <span class="n">the</span> <span class="n">Vary</span> <span class="n">header</span><span class="o">.</span>
-</pre></div>
-
-
+<p>Run the command <code>traffic_line -x</code> to apply the configuration changes. </p>
 </li>
 </ol>
-<dl>
-<dt><code>_proxy.config.http.cache.vary_default_text_</code></dt>
-<dd>Set this variable to specify the HTTP header field on which you want to vary 
-    if the request is for text: for example, an HTML document.</dd>
-<dt><code>_proxy.config.http.cache.vary_default_images_</code></dt>
-<dd>Set this variable to specify the HTTP header field on which you want to vary 
-    if the request is for images: for example, a <code>.gif</code> file.</dd>
-<dt><code>_proxy.config.http.cache.vary_default_other_</code></dt>
-<dd>Set this variable to specify the HTTP header field on which you want to vary 
-    if the request is for anything other than text or image.</dd>
-</dl>
-<ol>
-<li><strong>Note:</strong> If you specify <code>Cookie</code> as the header field on which to vary in the above variables, then make sure that the variable <code>_proxy.config.http.cache.cache_responses_to_cookies_</code> is set appropriately. <br />
- For example, if you set <code>_proxy.config.http.cache.cache_responses_to_cookies_</code> to 2 (cache responses to cookies of image type only) and set the <code>_proxy.config.http.cache.vary_default_text_</code> variable to specify cookie, then alternates by cookie will not apply to text. </li>
-<li>Save and close the <code>records.config</code> file. </li>
-<li>Navigate to the Traffic Server <code>bin</code> directory. </li>
-<li>Run the command <code>traffic_line -x</code> to apply the configuration changes. </li>
-</ol>
 <h3 id="LimitingNumberofAlternatesforanObject">Limiting the Number of Alternates for an Object</h3>
 <p>You can limit the number of alternates Traffic Server can cache per object 
 (the default is 3). </p>
@@ -749,17 +593,9 @@ can look up the URL in the index very qu
 available alternates in the object store.</p>
 <h5 id="limitnumberofalternates">To limit the number of alternates:</h5>
 <ol>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variable:</li>
-<li>
-<dl>
-<dt><em><code>proxy.config.cache.limits.http.max_alts</code></em></dt>
-<dd>Set this variable to specify the maximum number of alternate versions of an
-    object you want Traffic Server to cache. The default value is three.</dd>
-</dl>
-</li>
-<li>Save and close the <code>records.config</code> file. </li>
-<li>Navigate to the Traffic Server <code>bin</code> directory. </li>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>set <a href="../configuration-files/records.config#proxy.config.cache.limits.http.max_alts"><em><code>proxy.config.cache.limits.http.max_alts</code></em></a>
+   to specify the maximum number of alternate versions of an object you want Traffic Server to cache.</li>
 <li>Run the command <code>traffic_line -x</code> to apply the configuration changes. </li>
 </ol>
 <h2 id="UsingCongestionControl">Using Congestion Control</h2>
@@ -776,21 +612,13 @@ server later. </p>
    the page Traffic Server sends to the client when a server becomes congested 
    if Traffic Server tracks the origin servers per IP address or per hostname </li>
 </ul>
-<h5 id="enableconfigureCongestionControloption">To enable and configure the Congestion Control option :</h5>
+<h5 id="enableconfigureCongestionControloption">To enable and configure the Congestion Control option:</h5>
 <ol>
-<li>In a text editor, open the <code>records.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Edit the following variable:</li>
-<li>
-<dl>
-<dt><em><code>proxy.config.http.congestion_control.enabled</code></em></dt>
-<dd>Set this variable to 1 to enable the congestion control option.</dd>
-</dl>
-</li>
-<li>Save and close the <code>records.config</code> file. </li>
-<li>In a text editor, open the <code>congestion.config</code> file located in the Traffic Server <code>config</code> directory. </li>
-<li>Enter rules to specify which origin servers are tracked for congestion and the timeout values Traffic Server uses to determine congestion. Refer to <a href="files.htm#congestion.config">congestion.config</a> for the rule format. </li>
-<li>Save and close the <code>congestion.config</code> file. </li>
-<li>Navigate to the Traffic Server <code>bin</code> directory. </li>
+<li>In <a href="../configuration-files/records.config"><code>records.config</code></a></li>
+<li>set <a href="../configuration-files/records.config#proxy.config.http.congestion_control.enabled"><em><code>proxy.config.http.congestion_control.enabled</code></em></a>
+   to 1 to enable the congestion control option.</li>
+<li>In <a href="../configuration-files/congestion.config"><code>congestion.config</code></a></li>
+<li>Enter rules to specify which origin servers are tracked for congestion and the timeout values Traffic Server uses to determine congestion.</li>
 <li>Run the command <code>traffic_line -x</code> to apply the configuration changes. </li>
 </ol>
     </div>



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