Desktop's HDX Channel Test

The key factors influencing user experience in a virtual desktop infrastructure are the latencies experienced by the user while connecting to the desktop via ICA and the bandwidth used when a user interacts with a virtual desktop. High latency and excessive bandwidth consumption can often slowdown access to desktops, thereby significantly delaying subsequent user operations. Hence, monitoring the latency and bandwidth usage of the ICA communication channel between the user terminal and the virtual desktops is essential.

The Desktop's HDX Channel test auto-discovers the virtual desktops on the ESX host and the users who are currently connected to each desktop.  For each such user, the test monitors the communication between a user and the virtual desktop, and reports the following:

  • The latency experienced by each user session;
  • The bandwidth used by the incoming and outgoing data/audio/multimedia traffic over the ICA communication channel between each user and virtual desktop;

Using this test, an administrator can identify user sessions that are being impacted by high latency and abnormal bandwidth usage. In addition, the test also reveals the type of traffic that is causing excessive bandwidth usage, thereby providing pointers to how the client configuration can be fine-tuned in order to reduce bandwidth consumption and improve performance.

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 VMware vSphere ESX as the Component type, set Performance as the Test type, choose this test from the disabled tests list, and click on the >> button to move the test to the enabled tests list.

Note:

This test will report metrics only if the following conditions are fulfilled:

  • The test is applicable to Windows VMs only.
  • The VMs being monitored should be managed by XenDesktop Broker.
  • The Virtual Desktop Agent software should have been installed on the VMs.
  • The ICA Session performance object should be enabled on the VMs.

Target of the test : An ESX server host

Agent deploying the test : An internal/remote agent

Outputs of the test : One set of results for every user who is connected to a virtual desktop via ICA.

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 specified host listens. By default, this is NULL.
  4. esx user and esx password - In order to enable the test to extract the desired metrics from a target ESX server, you need to configure the test with an ESX USER and ESX PASSWORD. The user credentials to be passed here depend upon the mechanism used by the eG agent for collecting performance statistics from the ESX server and its VMs. These monitoring methodologies and their corresponding configuration requirements have been discussed hereunder:

    • Monitoring using the web services interface of the ESX server: Starting with ESX server 3.0, a VMware ESX server offers a web service interface using which the eG agent collects metrics from the ESX server. The VMware VI SDK is used by the agent to implement the web services interface. To use this interface for monitoring, this test should be configured with an ESX USER who has “Read-only” privileges to the target ESX server. By default, the root user is authorized to execute the test. However, it is preferable that you create a new user on the target ESX host and assign the “Read-only” role to him/her. The steps for achieving this have been elaborately discussed in Creating a New User with Read-Only Privileges to the ESX Server section.

      ESX servers terminate user sessions based on timeout periods. The default timeout period is 30 mins. When you stop an agent, sessions currently in use by the agent will remain open for this timeout period until ESX times out the session. If the agent is restarted within the timeout period, it will open a new set of sessions. If you want the eG agent to close already existing sessions before it opens new sessions, then you would have to configure all the tests with the credentials of an ESX user with permissions to View and stop sessions (prior to vSphere/ESX server 4.1, this was called the View and Terminate Sessions privilege). To know how to grant this permission to an ESX user, refer to .

    • Monitoring using the vCenter in the target environment: By default, the eG agent connects to each ESX server and collects metrics from it. While this approach scales well, it requires additional configuration for each server being monitored. For example, separate user accounts may need to be created on each server for read-only access to VM details. While monitoring large virtualized installations however, the agents can be optionally configured to monitor ESX servers using the statistics already available with different vCenter installations in the environment.

    In this case therefore, the ESX USER and ESX PASSWORD that you specify should be that of an Administrator or Virtual Machine Administrator in vCenter. However, if, owing to security constraints, you prefer not to use the credentials of such users, then, you can create a special role on vCenter with ‘Read-only’ privileges.

    Refer to Section Assigning the ‘Read-Only’ Role to a Local/Domain User to vCenter section of this document to know how to create a user on vCenter.

    If the ESX server for which this test is being configured had been discovered via vCenter, then the eG manager automatically populates the esx user and esx password text boxes with the vCenter user credentials using which the ESX discovery was performed.

    Like ESX servers, vCenter servers too terminate user sessions based on timeout periods. The default timeout period is 30 mins. When you stop an agent, sessions currently in use by the agent will remain open for this timeout period until vCenter times out the session. If the agent is restarted within the timeout period, it will open a new set of sessions. If you want the eG agent to close already existing sessions before it opens new sessions, then you would have to configure all the tests with the credentials of a vCenter user with permissions to View and stop sessions (prior to vCenter 4.1, this was called the View and Terminate Sessions permission). To know how to grant this permission to a user to vCenter, refer to Creating a Special Role on vCenter and Assigning the Role to a Local/Domain User section.

    When the eG agent is started/restarted, it first attempts to connect to the vCenter server and terminate all existing sessions for the user whose credentials have been provided for the tests. This is done to ensure that unnecessary sessions do not remain established in the vCenter server for the session timeout period.  Ideally, you should create a separate user account with the required credentials and use this for the test configurations. If you provide the credentials for an existing user for the test configuration, when the eG agent starts/restarts, it will close all existing sessions for this user (including sessions you may have opened using the Virtual Infrastructure client). Hence, in this case, you may notice that your VI client sessions are terminated when the eG agent starts/restarts.

  5. confirm password - Confirm the password by retyping it here.
  6. ssl - By default, the ESX server is SSL-enabled. Accordingly, the SSL flag is set to Yes by default. This indicates that the eG agent will communicate with the ESX server via HTTPS by default.

    Like the ESX sever, the vCenter is also SSL-enabled by default. If you have chosen to use the vCenter for monitoring, then you have to set the SSL flag to Yes.

  7. webport - By default, in most virtualized environments, the vSphere/ESX server and vCenter listen on port 80 (if not SSL-enabled) or on port 443 (if SSL-enabled). This implies that while monitoring an SSL-enabled vSphere/ESX server directly, the eG agent, by default, connects to port 443 of the vSphere/ESX server to pull out metrics, and while monitoring a non-SSL-enabled server, the eG agent connects to port 80. Similarly, while monitoring a vSphere/ESX server via an SSL-enabled vCenter, the eG agent connects to port 443 of vCenter to pull out the metrics, and while monitoring via a non-SSL-enabled vCenter, the eG agent connects to port 80 of vCenter. 

    Accordingly, the webport parameter is set to 80 or 443 depending upon the status of the ssl flag.  In some environments however, the default ports 80 or 443 might not apply. In such a case, against the webport parameter, you can specify the exact port at which the vSphere/ESX server or vCenter in your environment listens so that the eG agent communicates with that port.

  8. VIRTUAL CENTER - If the eG manager had discovered the target ESX server by connecting to vCenter, then the IP address of the vCenter server used for discovering this ESX server would be automatically displayed against the vIRTUAL center parameter; similarly, the esx user and esx password text boxes will be automatically populated with the vCenter user credentials, using which ESX discovery was performed.

    If this ESX server has not been discovered using vCenter, but you still want to monitor the ESX server via vCenter, then select the IP address of the vCenter host that you wish to use for monitoring the ESX server from the vIRTUAL center list. By default, this list is populated with the IP address of all vCenter hosts that were added to the eG Enterprise system at the time of discovery. Upon selection, the esx user and esx password that were pre-configured for that vCenter server will be automatically displayed against the respective text boxes.

    On the other hand, if the IP address of the vCenter server of interest to you is not available in the list, then, you can add the details of the vCenter server on-the-fly, by selecting the Other option from the vIRTUAL center list. This will invoke the add vcenter server details page. Refer to Adding the Details of a vCenter Server for Guest Discovery section.

    On the other hand, if you want the eG agent to behave in the default manner -i.e., communicate with each ESX server for monitoring it - then set the VIRTUAL CENTER parameter to ‘none’. In this case, the ESX USER and ESX PASSWORD parameters can be configured with the credentials of a user who has at least ‘Read-only’ privileges to the target ESX server.

  9. inside view using - By default, this test communicates with every VM remotely and extracts “inside view” metrics. Therefore, by default, the inside view using flag is set to Remote connection to VM (Windows).

    Typically, to establish this remote connection with Windows VMs in particular, eG Enterprise requires that the eG agent be configured with domain administrator privileges. In high-security environments, where the IT staff might have reservations about exposing the credentials of their domain administrators, this approach to extracting “inside view” metrics might not be preferred. In such environments therefore, eG Enterprise provides administrators the option to deploy a piece of software called the eG VM Agent (Windows) on every Windows VM; this VM agent allows the eG agent to collect “inside view” metrics from the Windows VMs without domain administrator rights. Refer to Configuring the eG Agent to Collect Current Hardware Status Metrics section for more details on the eG VM Agent. To ensure that the “inside view” of Windows VMs is obtained using the eG VM Agent, set the inside view using flag to eG VM Agent (Windows). Once this is done, you can set the domain, admin user, and admin password parameters to none.

  10. domain, admin user, admin password, and confirm password - By default, this test connects to each virtual guest remotely and attempts to collect “inside view” metrics. In order to obtain a remote connection, the test must be configured with user privileges that allow remote communication with the virtual guests. The first step towards this is to specify the DOMAIN within which the virtual guests reside. The admin user and admin password will change according to the domain specification. Discussed below are the different values that the domain parameter can take, and how they impact the admin user and admin password specifications:

    • If the VMs belong to a single domainIf the guests belong to a specific domain, then specify the name of that domain against the domain parameter. In this case, any administrative user in that domain will have remote access to all the virtual guests. Therefore, an administrator account in the given domain can be provided in the ADMIN USER field and the corresponding password in the ADMIN PASSWORD field. Confirm the password by retyping it in the CONFIRM PASSWORD text box.
    • If the guests do not belong to any domain (as in the case of Linux/Solaris guests) :  In this case, specify “none” in the DOMAIN field, and specify a local administrator account name in the ADMIN USER below.

      Prior to this, you need to ensure that the same local administrator account is available or is explicitly created on each of the virtual machines to be monitored. Then, proceed to provide the password of the ADMIN USER against ADMIN PASSWORD, and confirm the password by retyping it in the CONFIRM PASSWORD text box.

      If key-based authentication is implemented between the eG agent and the SSH daemon of a Linux guest, then, in the admin user text box, enter the name of the user whose <user_home_dir> (on that Linux guest) contains a .ssh directory with the public key file named authorized_keys. The admin password in this case will be the passphrase of the public key; the default public key file that is bundled with the eG agent takes the password eginnovations. Specify this as the admin password if you are using the default private/public key pair that is bundled with the eG agent to implement key-based authentication. On the other hand, if you are generating a new public/private key pair for this purpose, then use the passphrase that you provide while generating the pair. For the detailed procedure on Implementing Key-based Authentication refer to Troubleshooting the Failure of the eG Remote Agent to Connect to or Report Measures for Linux Guests section.

    • If the guests belong to different domains - In this case, you might want to provide multiple domain names. If this is done, then, to access the guests in every configured domain, the test should be configured with the required user privileges; this implies that along with multiple DOMAIN names, multiple ADMIN USER names and ADMIN PASSWORDs would also have to be provided. To help administrators provide these user details quickly and easily, the eG administrative interface embeds a special configuration page. To access this page, simply click on the Click here hyperlink that appears just above the parameters of this test in the test configuration page. To know how to use the special page, refer to Desktop's HDX Channel Testsection.
    • If the inside view using flag is set to ‘eG VM Agent (Windows)’ - In this case, the inside view can be obtained without domain administrator privileges. Therefore, set the domain, admin user, and admin password parameters to none.
  11. exclude vms - Administrators of some virtualized environments may not want to monitor some of their less-critical VMs - for instance, VM templates - both from ‘outside’ and from ‘inside’. The eG agent in this case can be configured to completely exclude such VMs from its monitoring purview. To achieve this, provide a comma-separated list of VMs to be excluded from monitoring in the exclude vms text box. Instead of VMs, VM name patterns can also be provided here in a comma-separated list. For example, your exclude vms specification can be: *xp,*lin*,win*,vista. Here, the * (asterisk) is used to denote leading and trailing spaces (as the case may be). By default, this parameter is set to none indicating that the eG agent obtains the inside and outside views of all VMs on a virtual host by default. By providing a comma-separated list of VMs/VM name patterns in the exclude vms text box, you can make sure the eG agent stops collecting ‘inside’ and ‘outside’ view metrics for a configured set of VMs.
  12. ignore vms inside view - Administrators of some high security VMware environments might not have permissions to internally monitor one/more VMs. The eG agent can be configured to not obtain the inside view of such ‘inaccessible’ VMs using the ignore vms inside view parameter. Against this parameter, you can provide a comma-separated list of VM names, or VM name patterns, for which the inside view need not be obtained. For instance, your ignore vms inside view specification can be: *xp,*lin*,win*,vista. Here, the * (asterisk) is used to denote leading and trailing spaces (as the case may be). By default, this parameter is set to none indicating that the eG agent obtains the inside view of all VMs on an ESX host by default.

    Note:

    While performing VM discovery, the eG agent will not discover the operating system of the VMs configured in the ignore vms inside view text box.

  13. ignore winnt - By default, the eG agent does not support the inside view for VMs executing on Windows NT operating systems. Accordingly, the ignore winnt flag is set to Yes by default.
  14. REPORT BY USER - While monitoring a VMware ESX server, the REPORT BY USER flag is set to No by default, indicating that by default, the guest operating systems on the ESX server are identified using the hostname specified in the operating system. On the other hand, while monitoring VMware Desktop environments, this flag is set to YES by default; this implies that in case of VDI servers, by default, the guests will be identified using the login of the user who is accessing the guest OS. In other words, in VDI environments, this test will, by default, report measures for every username_on_virtualmachinename.
  15. REPORT POWERED OS - This flag becomes relevant only if the REPORT BY USER flag is set to ‘Yes’.

    If the REPORT POWERED OS flag is set to Yes (which is the default setting), then this test will report measures for even those VMs that do not have any users logged in currently. Such guests will be identified by their virtual machine name and not by the username_on_virtualmachinename. On the other hand, if the REPORT POWERED OS flag is set to No, then this test will not report measures for those VMs to which no users are logged in currently.

Measurements made by the test
Measurement Description Measurement Unit Interpretation

Screen refresh latency - avg:

Indicates the average time interval measured at the client between the first step (user action) and the last step (graphical response displayed) of this user's session.

This measure maps to the 'ICA RTT' measure in Citrix Director.

Secs

This is a measurement of the screen lag that a user experiences while interacting with a virtual desktop.

Comparing the value of this measure across users will enable administrators to quickly and accurately identify users who are experiencing higher latency when interacting with a virtual desktop.

Screen refresh latency - deviation

Indicates the difference between the minimum and maximum measured latency values for this user session.

Secs

Ideally, the deviation in latencies over a session should be minimum so as to provide a consistent experience for the user.

Screen refresh latency - last:

Represents the client latency for the last request from a user. The latency is measured based on packets sent to and from each user during a session - this includes network delay plus virtual desktop side processing delays.

Secs

A consistently high latency may be indicative of poor user experience with the virtual desktop. Possible reasons for an increase in latency could be increased network delays, network congestion, etc. Typically, latencies will be below 5 secs.  

Audio bandwidth input:

Indicates the bandwidth used while transmitting sound/audio to this user.

Kbps

Comparing these values across users will reveal which user is sending/receiving bandwidth-intensive sound/audio files over the ICA channel.

To minimize bandwidth consumption, you may want to consider disabling client audio mapping.

Audio bandwidth output:

Indicates the bandwidth used while receiving sound/audio from this user.

Kbps

COM bandwidth input:

Indicates the bandwidth used when sending data to this user’s COM port.

 

Kbps

Comparing these values across users will reveal which user’s COM port is sending/receiving bandwidth-intensive data over the ICA channel.

COM bandwidth ouput:

Indicates the bandwidth used when receiving data from this user’s COM port.

Kbps

Drive bandwidth input:

Indicates the bandwidth used when this user performs file operations on the mapped drive on the virtual desktop.

Kbps

Comparing the values of these measures across users will reveal which user is performing bandwidth-intensive file operations over the ICA channel.

If bandwidth consumption is too high, you may want to consider disabling client drive mapping on the client device. Client drive mapping allows users logged on to a virtual desktop from a client device to access their local drives transparently from the ICA session. Alternatively, you can conserve bandwidth by even refraining from accessing large files with client drive mapping over the ICA connection.

Drive bandwidth output:

Indicates the bandwidth used when the virtual desktop performs file operations on the client’s drive.

Kbps

Printer bandwidth input:

Indicates the bandwidth used when this user prints to a desktop printer over the ICA channel.

Kbps

Comparing the values of these measures across users will reveal which user is issuing bandwidth-intensive print commands over the ICA channel.

If bandwidth consumption is too high, you may want to consider disabling printing. Alternatively, you can avoid printing large documents over the ICA connection.

Printer bandwidth output:

Indicates the bandwidth used when the desktop responds to print jobs issued by this user. 

Kbps

Session bandwidth input:

Indicates the bandwidth used from this user to the virtual desktop for a session

Kbps

Comparing the values of these measures across users will reveal which user and which virtual desktop is performing bandwidth-intensive operations for a session.

 

Session bandwidth output:

Indicates the bandwidth used from the virtual desktop to this user for a session.

Kbps

Session compression input:

Indicates the compression ratio used from this user to the virtual desktop for a session.

Number

Compression reduces the size of the data that is transacted over the ICA channel.

Comparing the values of these measures across users will reveal which client has been configured with a very low and a very high compression ratio.

In the event of high bandwidth usage over an ICA channel, you can set a higher compression ratio for the corresponding client and thus reduce bandwidth consumption.

 

Session compression output:

Indicates the compression ratio used from the virtual desktop to this user for a session.

Number

Speed screen data channel bandwidth input:

Indicates the bandwidth used from this user to the virtual desktop for data channel traffic.

Kbps

Comparing the values of these measures across users will reveal which user has been transmitting/receiving bandwidth-intensive data channel traffic.

 

Speed screen data channel bandwidth output:

Indicates the bandwidth used from virtual desktop to this user for data channel traffic.

Kbps

Speed screen multimedia acceleration bandwidth input:

Indicates the bandwidth used from this user to virtual desktop for multimedia traffic.

Kbps

Comparing the values of these measures across users will reveal which user has been transmitting/receiving bandwidth-intensive multimedia traffic.

 

 

Speed screen multimedia acceleration bandwidth output:

Indicates the bandwidth used from the virtual desktop to this user for multimedia traffic

Kbps

HDX media stream for flash data bandwidth input:

Indicates the bandwidth used from this user to virtual desktop for flash data traffic.

Kbps

Comparing the values of these measures across users will reveal which user has been transmitting/receiving bandwidth-intensive flash data.

 

 

HDX media stream for flash data bandwidth output:

Indicates the bandwidth used from the virtual desktop to this user for flash data traffic

Kbps

 

USB bandwidth input:

Indicates the bandwidth used from this user to the virtual desktop for the USB port-related traffic.

Kbps

Comparing the values of these measures across users will reveal which user has been transmitting/receiving bandwidth-intensive USB traffic.

 

USB bandwidth output:

Indicates the bandwidth used from the virtual desktop to this user for the USB port-related traffic.

Kbps

Session line speed input:

Indicates the average line speed of all the sessions of this user to the desktop.

KB/Sec

 

Session line speed output:

Indicates the average line speed from the desktop to this user.

KB/Sec

 

Bandwidth usage of user's session:

Indicates the percentage HDX bandwidth consumption of this user.

Percent

Compare the value of this measure across users to know which user is consuming the maximum HDX bandwidth.

Thinwire bandwidth input:

Indicates the bandwidth used from user client to desktop for ThinWire traffic.

Kbps

Typically, ICA traffic is comprised of many small packets, as well as a some large packets. Large packets are commonly generated for initial session screen paints and printing jobs, whereas the ongoing user session is principally comprised of many small packets. For the most part, these small packets are the highest priority ICA data called Thinwire. Thinwire incorporates mouse movements and keystrokes. 

Compare the value of these measures across users to know which user’s keystrokes and mouse movements are generating bandwidth-intensive traffic.

Note:

This measure will report the value 0, if Framehawk is enabled for a user.

Thinwire bandwith output:

Indicates the bandwidth used from desktop to user client for ThinWire traffic.

Kbps

Note:

This measure will report the value 0, if Framehawk is enabled for a user.

Seamless bandwidth input:

Indicates the bandwidth used from user client to desktop for published applications that are not embedded in a session window.

Kbps

Compare the value of these measures across users to know which user is accessing bandwidth-intensive applications that are not in a session window.

Seamless bandwidth output:

Indicates the bandwidth used from desktop to user client for published applications that are not embedded in a session window.

Kbps

 

Resource shares:

Indicates the total number of resource shares used by this user.

Number

By comparing the value of this measure across users, you can identify the user who is hogging the resources.

Frame rate:

Indicates the rate at which frames are processed during this user session.

Frames/Sec

FPS is how fast your graphics card can output individual frames each second. It is the most time-tested and ideal measure of performance of a GPU. Higher the value of this measure, healthier is the GPU.

Framehawk frame rate:

Indicates the rate at which frames are processed by the Framehawk virtual channel, if it is enabled for this user session.

Frames/Sec

The Framehawk virtual channel optimizes the delivery of virtual desktops and applications to users on broadband wireless connections, when high packet loss or congestion occurs.

A high value is desired for this measure, as it indicates faster delivery of applications to users, which in turn makes for a better user experience.  

You can compare the value of this measure with that of the Frame rate measure of a user to ascertain whether/not the Framehawk virtual channel has indeed enhanced that user’s experience with virtual desktops. If this comparison reveals that the value of this measure is higher than that of the Frame rate measure, it is a clear indicator of the effectiveness of the Framehawk virtual channel.

Note:

This measure will report the value 0 if Framehawk is not enabled for a user or if the device from which the user is accessing the virtual desktop does not support Framehawk.

Framehawk network bandwidth:

Indicates the bandwidth consumption of this user session when the Framehawk virtual delivery channel is used.

KB

This is a good measure of the effectiveness of Framehawk in optimizing the bandwidth usage over the virtual delivery channel. A low value is desired for this measure.

Note:

This measure will report the value 0 if Framehawk is not enabled for a user or if the device from which the user is accessing the virtual desktop does not support Framehawk.

Framehawk latency:

Indicates the latency experienced by this user session when the Framehawk virtual delivery channel is used.

Secs

To judge the effectiveness of Framehawk, compare the value of this measure with that of the Client network latency measure for a Framehawk-enabled user. If the comparison reveals a lower value for this measure, it implies that Framehawk has succeeded in minimizing the latencies over the delivery channel.

Note:

This measure will report the value 0 if Framehawk is not enabled for a user or if the device from which the user is accessing the virtual desktop does not support Framehawk.

Framehawk network loss:

Indicates the percentage of packet loss experienced by this user session when the Framehawk virtual delivery channel is used.

Percent

If the value of this measure is very low, it indicates that Framehawk has been very effective in minimizing the loss of packets that typically occur when data is transmitted or received over a channel.

Note:

This measure will report the value 0 if Framehawk is not enabled for a user or if the device from which the user is accessing the virtual desktop does not support Framehawk.

Client network latency:

Indicates the latency experienced by this user when transmitting/receiving data over the ICA channel.

This measure maps to the 'Network RTT' measure in Citrix Director.

Secs

A low value is a sign of the good health of the ICA channel.

User's connection quality indicator:

Indicates the connectivity of this user with the Citrix environment.

 

The values that this measure can report and their corresponding numeric values are discussed in the table above:

Measure Value Numeric Value
Poor connection 1
Weak connection 2

Strong connection

3

None

4

Note:

By default, this measure reports the Measure Values listed in the table above. In the graph of this measure however, the value of this measure is represented using their numeric equivalents only.

By default, Citrix recommends a standard computation of user’s connection quality indicator as mentioned in the table below:

Connection Quality Indicator How is the Connection Quality Indicator calculated?

Weak

Reported when

  • Bandwidth > 1MBPs
  • Latency <= 150ms
  • ICA RTT <= 180ms

Strong

Reported when

  • Bandwidth > 8 MBPs
  • Latency <= 150ms
  • ICA RTT <= 180ms

None

Reported when

  • Bandwidth <= 0 MBPs
  • Latency < 0
  • ICA RTT < 0

Poor

Reported when any condition other than the above is noticed.