Important things to know about upgrading to Domain Time II 4.1 from a previous version or from
a different time product.
Upgrading from Domain Time 1.x (DT1)
If you are upgrading an existing Domain Time 1.x installation to 4.1, upgrade your PDC first, then
any DCs, then finally any clients. This will ensure that all down-level machines continue working
while the upgrade is in progress. Don't forget that you can install or upgrade over the network.
See the Rolling Out Domain Time II page for instructions on performing
Upgrading from Domain Time II, versions 2.1 or later
In general, Domain Time II Version 2.1 and later Servers and Clients are completely interoperable (with two rare exceptions,
see below), so you can upgrade any machine at any time without disturbing the program's operation. For best results,
however, you should upgrade your servers first, then your clients.
Exceptions: The only instances of potential incompatibility among Domain Time II Versions are:
If a Version 3.1 or later Server is set to provide Heartbeat Broadcasts using the Heartbeat (With Data) format to 2.x Clients.
Only version 3.1 and later Clients can understand Heartbeat (With Data) broadcasts. See
When to use Heartbeats and NTP Broadcasts.
If a Server or Full Client version 2.5.b.20030212 or later is attempting to use only the Domain Time II TCP protocol get the
time from from an earlier version Server. Servers prior to 2.5.b.20030212 can't provide the Domain Time II TCP protocol.
We recommend using the Domain Time II Manager
or the Update Server program to handle upgrading
all your existing machines. These programs can investigate your network, automatically upgrade all your existing Domain
Time machines, and provide a list of other machines that need to be upgraded manually. See the Rolling Out
Domain Time II page for instructions on performing remote upgrades.
Upgrading from other time sync software
You should not install two time sync programs on the same machine. The results of running two time services simultaneously are
unpredictable, and usually not pretty. With the exception of Microsoft's Windows Time Service on Win2k or later (which Domain Time
II handles automatically during installation), you must remove any other time management program before installing Domain Time.
See the removal instructions provided by the manufacturer.
Microsoft's Windows Time service
Domain Time is much more accurate, reliable and easier to maintain than Windows Time, and also provides many additional important
benefits without sacrificing any functions that Windows Time provides. See the
Windows Time Service Issues for detailed info on the drawbacks of Windows Time.
If you install Domain Time on a machine that already has Windows Time installed, Domain Time will automatically configure the system to
allow the Windows Time service to run (for compatibility with applications that check for it) but Domain Time will handle time sync and
manage the system clock. See the Co-existing with the Windows Time Service page
for more details.