Configuring Custom Expressions

A custom expression is one that you create within the policy. When you create an expression, you configure the parameters for the expression.

You can also create custom client security expressions to refer to commonly used client security strings. This eases the process of configuring preauthentication policies and also in maintaining the configured expressions.

For example, you want to create a custom client security expression for Symantec AntiVirus 10 and make sure that the virus definitions are no more than three days old. Create a new policy and then configure the expression to specify the virus definitions.

The following procedure shows how to create a client security policy in a preauthentication policy. You can use the same steps in a session policy.

To create a preauthentication policy and custom client security expression

1. In the configuration utility, on the Configuration tab, in the navigation pane, expand NetScaler Gateway > Policies > Authentication/Authorization, and then click Pre-Authentication EPA.
2. In the details pane, click Add. The Create Pre-Authentication Policy dialog box opens.
3. In Name, type a name for the policy.
4. Next to Request Profile, click New.
5. In the Create Authentication Profile dialog box, in Name, type a name for the profile and in Action, select Allow and then click Create.
6. In the Create Pre-Authentication Policy dialog box, next to Match Any Expression, click Add.
7. In Expression Type, select Client Security.
8. Configure the following:
   1. In Component, select Anti-Virus.
   2. In Name, type a name for the application.
   3. In Qualifier, select Version.
   4. In Operator, select ==.
   5. In Value, type the value.
   6. In Freshness, type 3 and then click OK.
9. In the Create Pre-Authentication Policy dialog box, click Create and then click Close.

When you configure a custom expression, it is added to the Expression box in the policy dialog box.