Before you proceed
Before configuring expressions and policies, be sure you understand the relevant Citrix ADC feature and the structure of your data, as follows:
- Read the documentation on the relevant feature.
- Look at the data stream for the type of data that you want to configure.
You may want to run a trace on the type of traffic or content that you want to configure. This will give you an idea of the parameters and values, and operations on these parameters and values, that you need to specify in an expression.
Note: The Citrix ADC supports either classic or Advanced policy within a feature. You cannot have both types in the same feature. Over the past few releases, some Citrix ADC features have migrated from using classic policies and expressions to Advanced policy and expressions. If a feature of interest to you has changed to the Advanced policy format, you may have to manually migrate the older information. Following are guidelines for deciding if you need to migrate your policies:
- If you configured classic policies in a version of the Integrated Caching feature prior to release 9.0 and then upgrade to version 9.0 or later, there is no impact. All legacy policies are migrated to the Advanced policy format.
- For other features, you need to manually migrate classic policies and expressions to the Advanced syntax if the feature has migrated to the Advanced policy.