Product Documentation

Rewrite Action and Policy Examples

Mar 20, 2012

The examples in this section demonstrate how to configure rewrite to perform various useful tasks. The examples occur in the server room of Example Manufacturing Inc., a mid-sized manufacturing company that uses its Web site to manage a considerable portion of its sales, deliveries, and customer support.

Example Manufacturing has two domains: example.com for its Web site and email to customers, and example.net for its intranet. Customers use the Example Web site to place orders, request quotes, research products, and contact customer service and technical support.

As an important part of Example's revenue stream, the Web site must respond quickly and keep customer data confidential. Example therefore has several Web servers and uses Citrix NetScaler appliances to balance the Web site load and manage traffic to and from its Web servers.

The Example system administrators use the rewrite features to perform the following tasks:
Example 1: Delete old X-Forwarded-For and Client-IP Headers.
Example Inc. removes old X-Forwarded-For and Client-IP HTTP headers from incoming requests.
Example 2: Adding a Local Client-IP Header.
Example Inc. adds a new, local Client-IP header to incoming requests.
Example 3: Tagging Secure and Insecure Connections.
Example Inc. tags incoming requests with a header that indicates whether the connection is a secure connection.
Example 4: Mask the HTTP Server Type.
Example Inc. modifies the HTTP Server: header so that unauthorized users and malicious code cannot use that header to determine the HTTP server software it uses.
Example 5: Redirect an External URL to an Internal URL.
Example Inc. hides information about the actual names of its Web servers and the configuration of its server room from users, to make URLs on its Web site shorter and easier to remember, and to improve security on its site.
Example 6: Migrating Apache Rewrite Module Rules.
Example Inc. moved its Apache rewrite rules to a NetScaler appliance, translating the Apache PERL-based script syntax to the NetScaler rewrite rule syntax.
Example 7: Marketing Keyword Redirection.
The marketing department at Example Inc. sets up simplified URLs for certain predefined keyword searches on the company’s Web site.
Example 8: Redirect Queries to the Queried Server.
Example Inc. redirects certain query requests to the appropriate server.
Example 9: Home Page Redirection.
Example Inc. recently acquired a smaller competitor, and it now redirects requests for the acquired company’s home page to a page on its own Web site.

Each of these tasks requires that the system administrators create rewrite actions and policies and bind them to a valid bind point on the NetScaler.