Citrix Systems Network Router 9.2 User Manual

Where limit_identifier is a NetScaler function that indicates the type of traffic to 
be monitored. For an example, see 

. For more information on configuring 

limit identifiers, see the Citrix NetScaler Traffic Management Guide.

This prefix can be used in any NetScaler feature that uses advanced policies and 
expressions, such as Rewrite and Responder.

For complete instructions on configuring rate-limiting policies, see the Citrix 
NetScaler Traffic Management Guide. Following is an overview of configuring 
policies to control the rate of traffic.

1.

Optionally, configure a rate limit selector.

2.

Configure a rate limit identifier, and if you have configured a rate limit 
selector, include it in the rate limit identifier's definition. The rate limit 
identifier assesses particular types of traffic for a user-configured time 
interval, and returns a boolean TRUE if the amount of traffic exceeds a 
user-configured limit within the time interval.

3.

Configure an advanced policy that applies the rate limit identifier to 
particular types of data, for example, to HTTP requests with particular IP 
addresses or subnets to particular file types. The policy expression must be 
a compound expression that contains at least two components:

•

An expression that identifies traffic to which the rate limit identifier 
is applied, for example: 
http.req.url.contains(

myAspx.aspx

)

.

•

An expression that identifies a rate limit identifier, for example: 
sys.check_limit(

myLimitIdentifier

)

.

Following is a complete example of the policy rule:

http.req.url.contains("myAspx.aspx") && 

sys.check_limit("myLimitIdentifier")