Intel 1520 User Manual

Page of 176
Appendix A Caching Solutions and Performance
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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:
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
.
reverse_map real.janes_books.com www.janes_books.com