User Manual

Enterasys X-Pedition User Reference Manual 355
Web Caching
Bypassing Cache Servers
Some Web sites require source IP address authentication for user access, therefore HTTP requests
for these sites cannot be redirected to the cache servers. To specify the sites for which HTTP
requests are not redirected to the cache servers, enter the following command in Configure mode:
Proxy Server Redundancy
Some networks use proxy servers that receive HTTP requests on a non-standard port number (i.e.,
not port 80). When the proxy server is available, all HTTP requests are handled by the proxy server.
The X-Pedition can provide proxy server redundancy by transparently redirecting HTTP
connections to the cache servers should the proxy server fail. To achieve this, the X-Pedition must
be configured to redirect HTTP requests on the (non-standard) HTTP port used by the proxy server.
To redirect HTTP requests to a non-standard HTTP port number, enter the following command in
Configure mode:
Distributing Frequently-Accessed Sites Across Cache Servers
The X-Pedition uses the destination IP address of the HTTP request to determine which cache
server to send the request. However, if there is a Web site that is being accessed very frequently, the
cache server serving requests for this destination address may become overloaded with user
requests. You can specify that certain destination addresses be distributed across the cache servers
in a round-robin manner.
To distribute a specified destination address across cache servers, enter the following command in
Configure mode:
Define destination sites to which
HTTP requests are sent directly.
web-cache <cache-name> create bypass-list range
<ipaddr-range>|list <ipaddr-list>|acl <acl-
name>
Specify non-standard HTTP port. web-cache <cache-name> set http-port <port number>
Distribute destination address across
cache servers.
web-cache <cache-name> set round-robin range
<ipaddr-range>|list <ipaddr-list>