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10 Citrix NetScaler Policy Configuration and Reference Guide
• Integrated Caching: You use advanced expressions to configure a selector
for a content group in the Integrated Cache.
• Load Balancing: You use advanced expressions to configure token
extraction for a load balancing virtual server that uses the TOKEN method
for load balancing.
• Rewrite: You use advanced expressions to configure Rewrite actions.
• Rate-based policies: You use advanced expressions to configure Limit
Selectors when configuring a policy to control the rate of traffic to various
servers.
Following are a few simple examples of advanced expressions:
• An HTTP request URL contains no more than 500 characters.
http.req.url.length <= 500
• An HTTP request contains a cookie that has fewer than 500 characters.
http.req.cookie.length < 500
• An HTTP request URL contains a particular text string.
http.req.url.contains(".html")
About Classic Expressions
Classic expressions enable you to evaluate basic characteristics of data. They
have a structured syntax that performs string matching and other operations.
Following are a few simple examples of classic expressions:
• An HTTP response contains a particular type of Cache Control header.
res.http.header Cache-Control contains public
• An HTTP response contains image data.
res.http.header Content-Type contains image/
• An SSL request contains a certificate.
req.ssl.client.cert exists