Connectivity to Virtual Desktop Test

Sometimes, a virtual desktop could be in a powered-on state, but the failure of the virtual desktop operating system or any fatal error in its operations could have rendered the desktop inaccessible to Delivery Controller, and consequently, to users. In order to enable administrators to promptly detect such ‘hidden’ anomalies, the eG agent periodically runs a connectivity check on each virtual desktop using the Connectivity to Virtual Desktop test, and reports whether the virtual desktop is accessible over the network or not.

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 Citrix Delivery Controller 5.x 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. Finally, click the Update button.

Target of the test : A Citrix Delivery Controller 5.x

Agent deploying the test : An internal agent

Outputs of the test : One set of results for every virtual desktop managed by the monitored Delivery Controller.

Configurable parameters for the test
Parameter	Description
Test Period	How often should the test be executed.
Host	The IP address of the host for which this test is to be configured.
Port	Refers to the port used by the DDC. The default port number is 80.
Report by Groupname	By default, this flag is set to Yes, indicating that this test reports a set of measures for every desktopgroup:virtualdesktop combination, by default. To ensure that this test reports a set of measures for every virtualdesktop alone, set this flag to No.
Report by Controllername	By default, this flag is set to Yes. This implies that every desktopgroup:virtualdesktop pair for which this test reports metrics will be prefixed by the controllername as well. Every descriptor will hence be of the following format by default: Controllername->desktopgroup:virtualdesktop. If you want to remove the controllername prefix from the descriptors, then, set this flag to No.
ReportUnavailability	By default, this flag is set to No. This implies that, by default, the test will not report the unavailability of network connection to any virtual desktop. In other words, if the Network availability of desktopmeasure of this test registers the value 0 for any virtual desktop, then, by default, this test will not report any measure for that virtual desktop; under such circumstances, the corresponding virtual desktop 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 to a virtual desktop.
Packetsize	The size of packets used for the test (in bytes)
Packetcount	The number of packets to be transmitted during the test.
Timeout	How long after transmission should a packet be deemed lost (in seconds).
PacketInterval	Represents the interval (in milliseconds) between successive packet transmissions during the execution of the network test for a specific target.

Measurements made by the test
Measurement	Description	Measurement Unit	Interpretation
Average delay	Indicates the average delay between transmission of packet to a virtual desktop and receipt of the response to the packet at the source.	Secs	An increase in the value of this measure is a cause for concern. Given below are some common reasons for such an anomaly: The network between the virtual desktop and the eG external agent is congested. When there is an increase in traffic on the interconnecting network, data transmission can slow down, thereby increasing communication latency. The quality of the network connection between the eG external agent and the virtual desktop is sub-par. Poor signal quality, faulty transmission lines, etc. can result in an increase in packet loss and/or network latency. The virtual desktop is overloaded. If the virtual desktop is very busy, it takes longer to respond to requests, and this will result in an increase in latency. There are problems with network routingbetween the virtual desktop and the eG external agent. A faulty network router, routing loops, etc., can increase network latency. Check the detailed diagnosis of this test to track latency on the first three hops between the agent and the virtual desktop. The latency to each hop can be used to determine which hop the problem lies in.
Minimum delay	The minimum time between transmission of a packet and receipt of the response back.	Secs	A significant increase in the minimum round-trip time is often a sure sign of network congestion.
Packet loss	Indicates the percentage of packets lost during transmission from source to target and back.	Percent	A value close to 100% for this measure is a cause for concern. Given below are some common reasons for such an anomaly: The network between the virtual desktop and the eG external agent is congested. When there is an increase in traffic on the interconnecting network, packets may be dropped. The quality of the network connection between the eG external agent and the virtual desktop is sub-par. Poor signal quality, faulty transmission lines, etc. can result in an increase in packet loss and/or network latency. The virtual desktop is overloaded. If the virtual desktop is very busy, it takes longer to respond to requests, and this will result in packet drops. There are problems with network routingbetween the virtual desktop and the eG external agent. A faulty network router, routing loops, etc., can increase packet loss. Check the detailed diagnosis of this test to know the hops that are on the path from the external agent to target virtual desktop, and the packet loss on each hop. This information can be used to diagnose the hop(s) that could be causing excessive packet loss.
Network availability of desktop	Indicates whether the network connection is available or not.	Percent	A value of 100 indicates that the virtual desktop is connected. The value 0 indicates that the virtual desktop is not connected. Typically, the value 100 corresponds to a Packet loss of 0. The value 0 for this measure could mean that the target virtual desktop is either down or too busy, or the interconnecting network is down.