FAQ: How can I enable NTP and DT2 broadcasts in Domain Time?
This article applies to Domain Time II.
Last Updated: 11 June 2015
How can I enable NTP and DT2 broadcasts in Domain Time?
Domain Time supports NTP and DT2 broadcasts, the implementation differs somewhat by version.
Information for versions 5.x and later
Domain Time Server supports both sending and receiving NTP and DT2 broadcasts; Domain Time Client supports receiving only.
Information for versions 3.x and 4.x
Domain Time on these versions supports NTP and DT2 broadcasts, both sending and receiving in Domain Time II Server, and
receiving only in Domain Time II Full Client and, as of version 3.x, Ultra Thin Client. Domain Time II Thin Client
and other Domain Time components do not support NTP broadcasts.
Information for version 2.5 only
The procedure for enabling NTP broadcast support is detailed in the respective registry settings
pages for Full Client and Server. This page summarizes the settings and contains links to the
appropriate documentation pages.
Modifying Registry entries requires basic familiarity with the Windows Registry and its operations.
Incorrect changes to the Registry can result in unpredictable, perhaps non-repairable, damage, up to and including
a non-bootable system! Have a qualified technician make the changes for you if you are not comfortable with the
process. We cannot be responsible for registry problems.
Enabling NTP broadcast sending on Domain Time II Server
Set the Heartbeat Type to 2, and the Heartbeat Rate to the frequency you want. Zero means no heartbeats at all,
and any other number represents the number of seconds between pulses. You may also want to change the
NTP Broadcast Version value. The default is 2. See Server Registry Settings for
Note: Domain Time II Server will not begin sending NTP broadcasts until its own time has been set.
Enabling NTP broadcast reception on Domain Time II Server
Master or Independent Servers can receive NTP broadcasts. Slave Servers cannot. To receive NTP broadcasts on Server,
uncheck the Set this machine's machine from a trusted external time source checkbox on the Time Sources tab
of the control panel applet. Then edit the NTP Broadcast Min Interval (in minutes) and NTP Broadcast Sources
registry entries to indicate how often you are willing to accept broadcasts and from what sources.
See Server Registry Settings for complete information.
Note: You may also want to uncheck the Refuse to serve the time until this machine's clock has been set
checkbox on the Advanced tab of the Server's control panel applet. By default, Server will not provide the time to other
machines until it has verified its own time. When operating in NTP broadcast reception mode, Server will not serve the
time until it has received at least one broadcast.
Enabling NTP broadcast reception on Domain Time II Full Client
To receive NTP broadcasts on Full Client, you must set two registry values, and then specify the servers you want to use
on the Time Sources tab of the control panel applet. In the registry, set Honor NTP Broadcasts to True, and set
NTP Broadcast Min Interval (in minutes) to indicate how often you are willing to accept broadcasts. On the
control panel applet, uncheck the Automatic Configuration checkbox and specify the name or IP address of the
server(s) you want to accept broadcasts from on one (or more) of the server definition lines. You must set the Primary
Protocol to NTP/SNTP. You may mix NTP broadcast servers in with regular servers. If Client does not get a broadcast
often enough to keep it from checking the time normally, it will iterate through the listed servers trying each server
with the specified protocol until it finds one that responds.
See Full Client Registry Settings for complete information.