Product Documentation

Policies and Expressions

May 26, 2015

The following topics provide the conceptual and reference information that you require for configuring advanced policies on the Citrix® NetScaler® appliance.

You can also download a list of all the expressions supported on the NetScaler appliance and the hierarchical order in which they can be invoked. The reference is in a zip file which you can download from:

Introduction to Policies and Expressions

Describes the purpose of expressions, policies, and actions, and how different NetScaler applications make use of them.

Configuring Advanced Policies

Describes the structure of advanced policies and how to configure them individually and as policy banks.

Configuring Advanced Expressions: Getting Started

Describes expression syntax and semantics, and briefly introduces how to configure expressions and policies.

Advanced Expressions: Evaluating Text

Describes expressions that you configure when you want to operate on text (for example, the body of an HTTP POST request or the contents of a user certificate).

Advanced Expressions: Working with Dates, Times, and Numbers

Describes expressions that you configure when you want to operate on any type of numeric data (for example, the length of a URL, a client's IP address, or the date and time that an HTTP request was sent).

Advanced Expressions: Parsing HTTP, TCP, and UDP Data

Describes expressions for parsing IP and IPv6 addresses, MAC addresses, and data that is specific to HTTP and TCP traffic.

Advanced Expressions: Parsing SSL Certificates

Describes how to configure expressions for SSL traffic and client certificates, for example, how to retrieve the expiration date of a certificate or the certificate issuer.

Advanced Expressions: IP and MAC Addresses, Throughput, VLAN IDs

Describes expressions that you can use to work with any other client- or server-related data not discussed in other chapters.

Typecasting Data

Describes expressions for transforming data of one type to another.

Regular Expressions

Describes how to pass regular expressions as arguments to operators in advanced expressions.

Configuring Classic Policies and Expressions

Provides details on how to configure the simpler policies and expressions known as classic policies and classic expressions.

Expressions Reference

A reference for classic and advanced expression arguments.

Summary Examples of Advanced Expressions and Policies

Examples of classic and advanced expressions and policies, in both quick reference and tutorial format, that you can customize for your own use.

Tutorial Examples of Advanced Policies for Rewrite

Examples of advanced policies for use in the Rewrite feature.

Tutorial Examples of Classic Policies

Examples of classic policies for NetScaler features such as application firewall and SSL.

Migration of Apache mod_rewrite Rules to Advanced Policies

Examples of functions that were written using the Apache HTTP Server mod_rewrite engine, with examples of these functions after translation into Rewrite and Responder policies on the NetScaler.