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| |
| <html> |
| <head> |
| <meta name="viewport" content="width=device-width, initial-scale=1"> |
| <title>Rewrite Domains</title> |
| <link rel="stylesheet" href="doc.css"> |
| </head> |
| <body> |
| <!--#include virtual="_header.html" --> |
| |
| |
| <div id=content> |
| <h1>Rewrite Domains</h1> |
| |
| |
| |
| <h2>Configuration</h2> |
| <p> |
| The 'Rewrite Domains' filter is enabled by specifying: |
| <dl> |
| <dt>Apache:<dd><pre class="prettyprint" |
| >ModPagespeedEnableFilters rewrite_domains</pre> |
| <dt>Nginx:<dd><pre class="prettyprint" |
| >pagespeed EnableFilters rewrite_domains;</pre> |
| </dl> |
| <p> |
| in the configuration file. The filter is not enabled by default and |
| should be added manually to the configuration file. |
| </p> |
| <p> |
| <a name="DomainRewriteHyperlinks"></a> |
| By default <code>rewrite_domains</code> only applies to resources, but it can |
| optionally rewrite domains in hyperlinks as well: |
| </p> |
| <dl> |
| <dt>Apache:<dd><pre class="prettyprint" |
| >ModPagespeedDomainRewriteHyperlinks on</pre> |
| <dt>Nginx:<dd><pre class="prettyprint" |
| >pagespeed DomainRewriteHyperlinks on;</pre> |
| </dl> |
| |
| <h2>Description</h2> |
| <p> |
| This filter applies all <a href="domains">domain mapping |
| directives</a> specified in pagespeed.conf to web resources that |
| are <strong>not</strong> otherwise rewritten by PageSpeed. For |
| example, if a resource is not cacheable, or filters which affect the |
| resource are turned off, then it still may be desirable to apply |
| domain sharding. (Domain sharding is not applied to hyperlinks even if <code><a |
| href="#DomainRewriteHyperlinks">DomainRewriteHyperlinks</a></code> is enabled.) |
| |
| </p> |
| |
| <h2>Requirements</h2> |
| <p>It is the responsibility of the site administrator to set up the |
| shard entries in their DNS or CNAME configuration. Also, please see |
| the <a href="domains#equiv_servers">note</a> about the servers |
| for rewrite domains — this applies to sharded domains as well. The |
| sharded domains must have access to the same content as the original |
| domain. |
| </p> |
| |
| <h2>Risks</h2> |
| <p> |
| It is the responsbility of the site administrator to ensure that moving |
| resources onto domains does not create a security vulnerability. In particular, |
| if the target domain has cookies, then any JavaScript loaded from a resource |
| moved to a domain with cookies will gain access to those cookies. In general, |
| moving resources to a cookieless domain is a great way to improve security. Be |
| aware that CSS can load JavaScript in certain environments. |
| </p> |
| |
| |
| </div> |
| <!--#include virtual="_footer.html" --> |
| </body> |
| </html> |
