3Com SUPERSTACK 3 WEBCACHE 3000, User Manual

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Cache Bypass 187
deployed in Transparent cache mode. Cache Bypass is useful in the
unlikely event that you have a Transparent cache deployment (not Proxy
Relay) and find a Web site that does not operate correctly with the
Transparent cache. A small number of Web sites perform IP address
validation with the client machine that sent the Web request and will
refuse a connection if a Transparent Webcache is present.
If you administer an NBX system you may find that the Webcache times
out when retrieving Call Logging information. If this happens, add the
IP address of your NBX system to the Client Bypass list.
3Com maintains a list of IP addresses of Websites that do not work
correctly with Transparent Webcaches. Please check 3Com's
Knowledgebase for the current list. Enter the following URL into your
Web browser:
http://knowledgebase.3com.com
(correct at time of publication)
Cache Bypass allows you to prevent the Webcache from being involved in
requests to those particular Web sites. All requests to the Web sites that
you include in the Cache Bypass lists will completely bypass the
Webcache and go straight to the origin servers, ensuring that the Web
sites that did not work with a Transparent cache will function correctly.
The Web requests will not appear in the Access Log and will not be
subject to the access control settings that you make in the Web Site
Blocking or Filtering Exclusion commands.
Changes that you make to Cache Bypass are performed without
interrupting the caching service. The changes may, however, take a few
seconds to be implemented.
You can create two types of Cache Bypass list:
■
Client Bypass List
You can create a list of client machine IP addresses or address ranges.
All Web requests from those client machines will bypass the
Webcache and go straight to the origin server.
■
Web Site Bypass List
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