Configuration of VmgTimeSyncTest

Time synchronization is one of the most important dependencies of windows. A time protocol is responsible for determining the best available time information and converging the clocks to ensure that a consistent time is maintained across systems. By default, windows support a tolerance of plus or minus five minutes for clocks. If the time variance exceeds this setting, clients will be unable to authenticate and in the case of domain controllers, replication will not occur. It implements a time synchronization system based on Network Time Protocol (NTP).

NTP is a fault-tolerant, highly scalable time protocol and it is used for synchronizing computer clocks by using a designated reference clock. A reference clock is some device or machinery that spits out the current time. The special thing about these things is accuracy. Reference clocks must be accurately following some time standard. NTP will compute some additional statistical values based on the current time reported by the reference clock, which will describe the quality of time it sees. Among these values are: offset (or phase), jitter (or dispersion), frequency error, and stability. Thus each NTP server will maintain an estimate of the quality of its reference clocks and of itself.

This test reports the time difference between the reference clock and that of the target environment, and thus helps assess the quality of time seen by the desktop. With the help of this test, you can also easily determine whether the reference time changed recently.

The default parameters associated with this test are:

• The TEST PERIOD list box helps the user to decide how often this test needs to be executed.

• Specify the nick name of the target component for which this test is to be configured in the HOST text box.

• Indicate the port at which the host listens to in the PORT text box. By default, this is NULL.

• To obtain the ‘inside view’ of performance of the desktops - i.e., to measure the internal performance of the physical desktops - this test uses a light-weight eG VM Agent software deployed on each of the desktops. Accordingly, INSIDE VIEW USING parameter is by default set to eG VM Agent.

• The REPORT POWERED OS is relevant only for those tests that are mapped to the Physical Desktops Details layer. If this flag is set to Yes (which is the default setting), then the 'inside view' tests will report measures for even those physical desktops that do not have any users logged in currently. Such desktops will be identified by their name and not by the username_on_physicalmachinename. On the other hand, if this flag is set to No, then this test will not report measures for those physical desktops to which no users are logged in currently.

• REPORT BY USER flag is set to Yes by default. This implies that the physical machines in environments will always be identified using the login name of the user. In other words, this test will, by default, report measures for every username_on_physicalmachinename.

• IS CLOUD VMs flag is set to Yes by default. This implies that the physical machines in environments will always be identified using the login name of the user. In other words, this test will, by default, report measures for every username_on_physicalmachinename.

• If multiple components of the same component type are awaiting configuration, then an APPLY TO OTHER COMPONENTS check box will appear in this page. Clicking on this check box will allow you to apply the configuration to all/selected components of that type.

• Once the necessary values have been provided, clicking on the UPDATE button will register the changes made.

When changing the configuration for specific servers, a “*” beside the text box corresponding to the parameter signifies that these values have to be manually configured by the user. The parameter values that require to be configured will typically be prefixed with a “$” or contain a series of “*”. A value of "none" in the parameter value indicates that the corresponding parameter value can be changed if required.