Top Sources Test

In environments where the NetScaler appliance is deployed, external clients (Source IPs) communicate via the NetScaler appliance to access applications hosted on the servers (Destination IPs). The NetScaler appliance is deployed in front of the web or database servers and routes requests to the servers from the external clients through it. When multiple clients are sending requests to the servers through the NetScaler device, it is impossible for the administrators to keep track of which client is sending the maximum amount of data to the server through its requests. In order to identify the topmost clients who are contributing to the maximum data transfer between the client and the server, adminsitrators can use the Top Sources test. This test dynamically lists the top clients and for each client reports the amount of data sent from the client to the server and amount of data received by the client from the server. By comparing the measures reported by this test, administrators can identify the topmost client in terms of data transfer. 

This test is disabled by default. To enable the test, follow the Agents -> Tests -> Enable/Disable menu sequence in the eG administrative interface, pick Citrix NetScaler VPX/MPX as the Component type, select Performance as the Test type, choose this test from the list of disabled tests list, and click on the < button.

For this test to run and report metrics, the NetScaler device should be configured to create a Syslog file in a remote Syslog server, where the details of all interactions with the NetScaler appliance will be logged.

Creating a Syslog file in a remote Syslog server

To configure the Syslog server where this Syslog file should be created, do the following:

  1. Connect to the NetScaler management console from your browser using the URL: <http://NetScaler host:port>.
  2. Login to the NetScaler as an administrator.
  3. Figure 1 will then appear.

    Netscaler syslog 1

    Figure 1 : The NetScaler management console

  4. Expand the System node in Figure 1 and further expanding the Auditing node will lead you to the Syslog option. Then, click the Syslog option.

    Netscaler syslog 2

    Figure 2 : Figuring out the SysLog option

  5. This will bring up a Policies tab and a Servers tab in the right panel, where you can configure Policies for a Syslog server, configure a remote Syslog server and enable Syslog file creation on the server. Selecting the Servers tab will lead you to Figure 3.

    Netscaler syslog 3

    Figure 3 : Configuring the Syslog server where the Syslog file is to be created

  6. To configure a new Syslog server, click the Add button in Figure 3. Figure 4 will then appear.

    Netscaler syslog 4

    Figure 4 : Creating the new Syslog server

  7. Enter the Name of the Syslog server.
  8. Then enter the IP address of the Syslog server in the IP Address text box of Figure 3.
  9. Enter the Port at which the Syslog server listens.
  10. Then, indicate what details should be logged in the Syslog file. For the eG tests to work, set the Log Levels flag to ALL.
  11. Set the Time Zone to Local and select the check boxes against TCP Logging, ACL Logging, User Configurable Log Messages and AppFlow Logging. Even though the syslog file is populated with the log messages, the metrics will be displayed in the eG Monitor interface only when these checkboxed are checked.
  12. Click the Create button in Figure 3 to configure the Syslog server.

Target of the test : A NetScaler VPX/MPX

Agent deploying the test : A remote agent

Outputs of the test : One set of results for each Source IP address configured on the target Citrix NetScaler

Configurable parameters for the test
  1. Test period - How often should the test be executed
  2. Host - The host for which the test is to be configured.
  3. port – The port at which the host listens. By default, this is NULL.
  4. log file path – This test reports metrics by parsing a Syslog file. Specify the full path to the Syslog file here.
  5. sEARCH STRING – By default, the Syslog file may contain information relating to a number of servers that are inter linked with the target NetScaler appliance. In order to obtain the metrics of the target NetScaler appliance alone, specify the hostname or the IP address of the target NetScaler appliance for which the logs are to be read from the syslog file, in the SEARCH STRING text box. Using this search string the information in the Syslog file may be parsed and metrics may be collected.
  6. SEARCH STRING INDEX – Here, specify the cursor position after which the eG agent should search for the specified SEARCH STRING (or the position up to which the eG agent should ignore while searching for the specified SEARCH STRING) in the syslog file. For example, if the specified search string appears in the syslog file at the 17th position, then you may need to specify the SEARCH STRING INDEX as 16.
  7. REPORT TOP N FLOWS – Specify the number of descriptors that need to be taken into consideration while monitoring the target NetScaler appliance. By default, this test will report the Top -10 source IP addresses.
  8. DD FREQUENCY – Refers to the frequency with which detailed diagnosis measures are to be generated for this test. The default is 1:1. This indicates that, by default, detailed measures will be generated every time this test runs, and also every time the test detects a problem. You can modify this frequency, if you so desire. Also, if you intend to disable the detailed diagnosis capability for this test, you can do so by specifying none against dd frequency.
  9. DETAILED DIAGNOSIS – To make diagnosis more efficient and accurate, the eG Enterprise embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option.

    The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled:

    • The eG manager license should allow the detailed diagnosis capability
    • Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.
Measurements made by the test
Measurement Description Measurement Unit Interpretation

Total data sent:

Indicates the total amount of data sent from this client (source IP) to the server (destination IP).


Compare the value of this measure across the source IP addresses to know which source IP address is sending the maximum amount of data.

The detailed diagnosis of this measure if enabled, lists the Source IP, Destination IP, Start time, End Time, Total Bytes sent and Total Bytes received.

Total data received:

Indicates the total amount of data received by this client (source IP) from the server (destination IP).


Compare the value of this measure across the source IP addrsesses to know which source IP address is receiving the maximum amount of data.

The detailed diagnosis of this measure if enabled, lists the Source IP, Destination IP, Start time, End Time, Total Bytes sent and Total Bytes received.