11.2.5. Bandwidth control setting

Operation Confirmed Version:
 Citrix Netscaler VPX Version11.0 Build67.12 Standard Edition
For the Load Balancer, Rate Limiting function can define the maximum load of a specific interface.
With this function, adjustment based on the traffic set in real time is possible. As a result, excessive load to the server side can be reduced.

Method to set an upper limit of the performance to a Load Balancer interface will be introduced here.

Note

  • If throughput more than the specified threshold is consumed, new requests will be DROPped. But the throughput of the existing connection will not be restricted to keep it below the threshold.

Presumed case for sample setting

  • Assume that we want to set an upper limit of the communication performance (8192Kbps) to the client-side interface of the Load Balancer (192.168.2.11).

  • Also assume that if new communication request comes while the communication has reached the upper limit of the performance, we like to discard the packets.

Configuration diagram
Fig17101
From the [ Configuration ] menu, move to [ AppExpert ] → [ Rate Limiting ] → [ Limit Identifiers ].
Fig17102
After the Limit Identifiers screen is displayed, click [ Add ].
Fig17103
The Create Limit Identifier screen will be displayed. Input the information as the table below.

Setting Items

Setting value

Name

Ratelimit01 (any Limit Identifier name)

Selector Top_URL
Mode NONE
Threshold 1
Maximum Bandwidth (Kbps) 8192
Traps 0
Input the set values and click [ Create ].
Fig17104
The Limit Identifiers screen will be displayed. Check that the set Limit Identifier is displayed.
Fig17105
Proceed to [AppExpert], [Responder] and [Policies] in [Configuration] menu.
Fig17106
After the Responder Policies screen is displayed, click [ Add ].
Fig17107
The Create Responder Policy screen will be displayed. Input the information as the table below.

Setting Items

Setting value

Name

ResponderPolicy01 (any Responder Policy name)

Action DROP
Undefined-Result Action -Global undefined-result action-
Expression HTTP.REQ.URL.CONTAINS(“/”) && SYS.CHECK_LIMIT(“Ratelimit01”)

Note

Setting of Expression can be made on the Expression Editor screen after clicking [ Expression Editor ] but direct input of the set values is also possible.

Input the set values and click [ Create ].
Fig17108
As the Responder Policies screen will be displayed. Check that the set Responder Policy is displayed.
Fig17109
From the [ Configuration ] menu, move to [ Traffic Management ] → [ Load Balancing ] → [ Virtual Services ].
Fig17110
After the Virtual Services screen is displayed, select a Virtual Service you want to set the upper limit of the performance, and click [ Edit ].
Fig17111
The details screen of the Virtual Servers will be displayed. From [ Advanced Settings ] in the right side of the screen, click [ Policies ].
Fig17112
Click [ + ] in [ Policies ] section added to the details screen of the Virtual Servers.
Fig17113
The Choose Type screen will be displayed. Input the information as the table below.

Setting Items

Setting value

Choose Policy Responder
Choose Type Request
Input the set values and click [ Continue ].
Fig17114
The Choose Type screen will be displayed. Input the information as the table below.

Setting Items

Setting value

Select Policy ResponderPolicy01
Priority 100
Goto Expression END
Invoke LabelType None

Note

To set Select Policy. Click [ Click to select ] and select [ ResponderPolicy01 ] already set from the Responder Policies screen displayed.

Input the set values and click [ Bind ].
Fig17115
The details screen of the Virtual Servers will be displayed. Check that [ 1 Responder Policy ] is displayed in [ Policies ], and click [ Done ].
Fig17116
The Virtual Servers screen will be displayed.
Fig17117
This completes the setting of the upper limit of the performance to the Load Balancer Interface.

Operation check result

Start up two browser screens and access a web page.
We checked that on the second browser where the upper limit was exceeded, the communication is dropped and not displayed. Therefore, we have confirmed that it is restricted by the upper limit of the performance.
Fig17118