ICA Client Access Test

A Citrix environment is a shared environment in which multiple users connect to a Citrix XenApp server from remote terminals using the ICA protocol. One of the key factors influencing user experience in such an environment is the latency seen by the users when connecting to the server. High network latencies or packet losses during transmission can cause significant slow-downs in request processing by the server. Hence, monitoring latencies between the server and individual client terminals is important.

The IcaClient test is executed by the eG agent on a Citrix XenApp server. This test auto-discovers the users who are currently logged on to the server and the IP address from which they are connecting to the Citrix server.  For each user, the test monitors the quality of the link between the client and the Citrix server.

Using this test, an administrator can identify user sessions that are being impacted by high latencies or by excessive packet drops. In some cases, a Citrix server may regard a user session as active, even though the network link connecting the user terminal to the Citrix server has failed. The IcaClientTest alerts administrators to such situations.

This test is disabled by default. To enable the test, go to the enable / disable tests page using the menu sequence : Agents -> Tests -> Enable/Disable, pick the desired Component type, set Performance as the Test type, choose the test from the disabled tests list, and click on the < button to move the test to the ENABLED TESTS list. Finally, click the Update button.

Target of the test : A Citrix XenApp server

Agent deploying the test : An internal agent

Outputs of the test : One set of outputs for every user currently connected to the Citrix server

Configurable parameters for this 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
  4. displaydomain - By default, the DISPLAYDOMAIN flag is set to Yes; this indicates that the ICA Client Access test, by default, will report metrics for every domainname\username who is currently connected to the server. This way, administrators can quickly figure out which user is connecting to the server from which domain. You can set this flag to No to ensure that this test reports metrics for each username only.
  5. Packetsize - The size of packets used for the test (in bytes)
  6. Packetcount – The number of packets exchanged between the Citrix server and the user terminal during the test
  7. Timeout - How long after transmission should a packet be deemed lost (in seconds)
  8. PacketInterval - Represents the interval (in milliseconds) between successive packet transmissions during the execution of this test.
  9. reportunavailability – By default, this flag is set to No. This implies that, by default, the test will not report the unavailability of network connection between a user terminal and the Citrix server. In other words, if the Packet loss measure of this test registers the value 100% for any user, then, by default, this test will not report any measure for that user; under such circumstances, the corresponding user name will not appear as a descriptor of this test. You can set this flag to Yes, if you want the test to report and alert you to the unavailability of the network connection between a user terminal and the Citrix server.  
Measurements made by the test
Measurement Description Measurement Unit Interpretation

Number of user sessions:

Indicates the current number of sessions for a particular user

Number

The value 0 indicates that the user is not currently connected to the Citrix server.

Avg network latency:

Indicates the average delay between transmission of a request by the agent on a Citrix server and receipt of the response back from the user terminal.

Secs

Comparing the value of this measure across users will enable administrators to quickly and accurately identify users who are experiencing higher latency when connecting to a Citrix server.

Min network latency:

Indicates the minimum delay between transmission of a request by the agent on a Citrix server and receipt of the response back from the user terminal.

Secs

A significant increase in the minimum round-trip time is often a sure sign of a poor link between the server and a user's terminal.

Packet loss:

Indicates the percentage of packets lost during data exchange between the Citrix server and the user terminal.

Percent

Comparing the value of this measure across users will enable administrators to quickly and accurately identify users who are experiencing slowdowns because of poor performance on the network links between their terminals and the Citrix server.

Note:

  • If the same user is connecting to the Citrix server from multiple client terminals, the value of the Number of user sessions, Avg network latency, and Packet loss measures will be averaged across all the sessions of that user. The Min network latency measure, on the other hand, will display the least value reported for Minimum delay across all the sessions of that user.
  • When a user logs out, the number of sessions will be reduced by 1. If the number of user sessions becomes 0, the corresponding entry for that user in the eG user interface will be removed after a short period of time.
  • By default, the ICA Client Access test spawns a maximum of one thread at a time for monitoring each of the ICA connections to a Citrix server. Accordingly, the MaxIcaClientThreads parameter in the eg_tests.ini file (in the <eg_install_dir>\manager\config directory) is set to 1 by default. In large Citrix farms however, numerous concurrent users attempt to connect to the Citrix server from multiple remote client terminals. To enhance the efficiency of the test and to make sure that it scales to monitor the large number of ICA connections to the Citrix server, you might want to consider increasing the value of the MaxIcaClientThreads parameter. If this parameter is set to say, 15, then, it implies that the test will spawn a maximum of 15 threads at one shot, thus monitoring 15 ICA connections to the Citrix server, simultaneously.
  • Sometimes, the ICA Client Access test may not work on Citrix XenApp v6.5. This is because, some installations of Citrix XenApp v6.5 may not support the performance object named ICA Session, which the test uses for reporting metrics. In such cases, follow the steps given below to enable the ICA Session performance object and its counters:
  • Login to the Windows system that hosts the Citrix XenApp server v6.5.
  • Open the command prompt as Run as administrator.

  • Issue the following command at the prompt:

    regsvr32 c:\windows\system32\icaperf.dll