This map rule specifies the path /jazz for jazz.flute.org on the server big.server.net.

Generally, you use reverse proxy mode to support more than one origin server. In this case, all of the advertised host names resolve to the IP address or virtual IP address of the appliance (see Figure 6). Using host headers, the appliance is able to translate server requests for any number of servers into proxy requests for those servers.

If the appliance receives requests from older browsers that do not support host headers, then it can route these requests directly to a specific server, or send the browser to a URL containing information about the problem. See Setting server accelerator options‚ on page 43.

Web server redirects

Web servers often send redirect responses back to browsers. Redirects tell browsers to go to different pages. Web servers redirect for a variety of reasons. One reason is to balance server load. For instance, if a server is overloaded, it might redirect browsers to a less loaded server. Another reason might be when Web pages have moved to different locations. When the appliance is configured in server acceleration mode, it must readdress redirects from origin servers so that browsers are redirected to the appliance, not to another Web server.

To readdress redirects, the appliance uses reverse-map rules. For example, the reverse-map rule required to convert redirects from real.janes_books.com (if the appliance assumes the associated name www.janes_books.com) would be:

reverse_map real.janes_books.com www.janes_books.com

In general, when setting up document rewrite rules, each map rule should have one reverse-map rule, with the source URL and the destination URL of the map rule reversed in the reverse-map rule.

You create and modify document reverse-map rules from the Server Acceleration section of the Routing page. See Setting server accelerator options‚ on page 43 for more information on how to create reverse-map rules. For more information about how reverse-map rules work, see the following section, Examples of rules and translations.

Appendix A Caching Solutions and Performance

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Intel 1520 manual Web server redirects