Configure advanced policy expressions outside the context of a policy
A number of functions, including the following, can require an advanced policy expression that is not part of a policy:
Integrated Caching selectors:
You define multiple non-compound expressions (selectlets) in the definition of the selector. Each selectlet is in an implicit logical AND relationship with the others.
Load Balancing:
You configure an expression for the TOKEN method of load balancing for a load balancing virtual server.
Rewrite actions:
Expressions define the location of the rewrite action and the type of rewriting to be performed, depending on the type of rewrite action that you are configuring. For example, a DELETE action only uses a target expression. A REPLACE action uses a target expression and an expression to configure the replacement text.
Rate-based policies:
你使用先进的政策xpressions配置mit Selectors. You can use these selectors when configuring policies to throttle the rate of traffic to various servers. You define up to five non-compound expressions (selectlets) in the definition of the selector. Each selectlet is in an implicit logical AND with the others.
Configure an advanced policy expression outside a policy by using the CLI (cache selector example)
At the command prompt, type the following commands to configure an advanced policy expression outside a policy and verify the configuration:
- add cache selector \ \ - show cache selector \
Example:
> add cache selector mainpageSelector "http.req.cookie.value(\"ABC_def\")" "http.req.url.query.value(\"_ghi\")"selector "mainpageSelector" added Done > show cache selector mainpageSelector Name: mainpageSelector Expressions: 1) http.req.cookie.value("ABC_def") 2) http.req.url.query.value("_ghi") Done
Following is an equivalent command that uses the more readable q delimiter, as described inConfigure advanced policy expressions in a policy:
> add cache selector mainpageSelector2 q~http.req.cookie.value("ABC_def")~ q~http.req.url.query.value("_ghi")~selector "mainpageSelector2" added Done > show cache selector mainpageSelector2 Name: mainpageSelector2 Expressions: 1) http.req.cookie.value("ABC_def") 2) http.req.url.query.value("_ghi") Done