Virtual Desktop Client's Network Connection Test

A Virtual Desktop Infrastructure (VDI) is a shared environment in which multiple users connect to desktops hosted by virtual machines executing on a Hyper-V host from remote terminals. One of the key factors influencing user experience in such an environment is the latency seen by the users when connecting to a virtual desktop. High network latencies or packet losses during transmission can cause significant slow-downs in request processing by the desktop. Hence, monitoring latencies between the virtual desktop and individual client terminals is important.

The Virtual Desktop Client's Network Connection test is executed by the eG agent on a Hyper-V host. This test auto-discovers the virtual desktops on the host, the users who are currently logged on to each of the virtual desktops, and the IP address from which they are connecting to the virtual desktops.  For each user, the test monitors the quality of the link between the client and the virtual desktop.

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 virtual desktop may regard a user session as active, even though the network link connecting the user terminal to the virtual desktop has failed. The Terminal to Desktop Connection test alerts administrators to such situations.

Note:

This test will work on Windows VMs only.

Target of the test : A Hyper-V server

Agent executing the test : An internal agent

Output of the test : One set of results will be reported for the user who is currently logged into each Windows virtual desktop on the server

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. 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, 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 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 Windows Virtual Machines to Support theInside View Using the eG VM Agent 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.

  5. 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. Accordingly, the inside view using flag is set to Remote connection to VM (Windows) by default. To obtain a remote connection, the test must be configured with the privileges of an administrative user to the domain within which the guests reside. 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 domain:  If 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 VMs 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 Configuring Users for VM Monitoring.
    • If the inside view using flag is set to ‘eG VM Agent (Windows)’: On the other hand, if the inside view using flag is set to eG VM Agent (Windows), then it implies that the inside view can be obtained without domain administrator privileges. Therefore, set the domain, admin user, and admin password parameters to none.
  6. REPORT BY USER – For the Hyper-V monitoring model, the REPORT BY USER flag is set to NO by default, indicating that by default, the guest operating systems on the Hyper-V server are identified using the hostname specified in the operating system. On the other hand, for the Hyper-V VDI model, 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.
  7. 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 virtualmachine 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.   

  8. ignore vms inside view - Administrators of some high security Hyper-V 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 a Hyper-V 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.

  9. 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.
  10. 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.
  11. Packetsize - The size of packets used for the test (in bytes)
  12. Packetcount - The number of packets exchanged between the virtual desktop and the user terminal during the test
  13. Timeout - How long after transmission should a packet be deemed lost (in seconds)
  14. PacketInterval- Represents the interval (in milliseconds) between successive packet transmissions during the execution of this test.
  15. 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 a virtual desktop. 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 network connection between a user terminal and a virtual desktop. 
Measurements reported by the test
Measurement Description Measurement Unit Interpretation

Number of 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 virtual desktop.

Average delay

Indicates the average delay between transmission of a request by the agent on a virtual desktop 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 virtual desktop.

Minimum delay

Indicates the minimum delay between transmission of a request by the agent on a virtual desktop 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 desktop and a user's terminal.

Packet loss

Indicates the percentage of packets lost during data exchange between the virtual desktop 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 virtual desktop.

Note:

  • If the same user is connecting to the virtual desktop from multiple client terminals, the value of the Number of sessions, Average delay, and Packet loss measures will be averaged across all the sessions of that user. The Minimum delay 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.