Citrix Systems Network Router 9.2 User Manual
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Citrix NetScaler Policy Configuration and Reference Guide
You must also use a backslash to escape question marks and other backslashes on
the command line. For example, the expression
http.req.url.contains(“\?”)
the command line. For example, the expression
http.req.url.contains(“\?”)
requires a backslash so that the question
mark is parsed. Note that the backslash character will not appear on the command
line after you type the question mark. On the other hand, if you escape a
backslash (for example, in the expression
'http.req.url.contains("\\\\http")'
line after you type the question mark. On the other hand, if you escape a
backslash (for example, in the expression
'http.req.url.contains("\\\\http")'
), the escape characters are
echoed on the command line.
To make an entry more readable, you can escape the quotation marks for an entire
expression. At the start of the expression you enter the escape sequence “q” plus
one of the following special characters: /{<|~$^+=&%@`?.
expression. At the start of the expression you enter the escape sequence “q” plus
one of the following special characters: /{<|~$^+=&%@`?.
You enter only the special character at the end of the expression, as follows:
q
@
http.req.url.contains("sometext") && http.req.cookie.exists
@
q~http.req.url.contains("sometext") && http.req.cookie.exists~
Note that an expression that uses the { delimiter is closed with }.
For some features (for example, Integrated Caching and Responder), the
configuration utility’s policy configuration dialog box provides a secondary
dialog box for configuring expressions. This dialog box enables you to choose
from drop-down lists that show the available choices at each point during
expression configuration. You cannot use arithmetic operators in these
configuration dialogs, but most other advanced expression features are available.
To use arithmetic operators , write your expressions in free-form format.
configuration utility’s policy configuration dialog box provides a secondary
dialog box for configuring expressions. This dialog box enables you to choose
from drop-down lists that show the available choices at each point during
expression configuration. You cannot use arithmetic operators in these
configuration dialogs, but most other advanced expression features are available.
To use arithmetic operators , write your expressions in free-form format.
To configure an advanced policy rule by using the NetScaler command line
At the NetScaler command prompt, type:
add cache|dns|rewrite|cs policy policyName -rule expression
featureSpecificParameters
Following is an example of configuring a caching policy:
add cache policy cacheReports -rule
q~http.req.url.query.value("actionoverride").contains("branchReport
s")~ -action cache
To configure an advanced policy expression by using the configuration
utility
utility
1.
In the navigation pane, click the name of the feature where you want to
configure a policy, for example, you can select Integrated Caching,
Responder, DNS, Rewrite, or Content Switching, and then click Policies.
configure a policy, for example, you can select Integrated Caching,
Responder, DNS, Rewrite, or Content Switching, and then click Policies.
2.
Click Add.
3.
For most features, click in the Expression field. For Content Switching,
click Configure and then click Advanced Syntax.
click Configure and then click Advanced Syntax.