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Q174557: Time Sources Defined For The Windows NT Time Service

Article: Q174557
Product(s): Microsoft Windows NT
Version(s): MS-DOS:3.0; Win2000:95; winnt:3.5,3.51,4.0
Operating System(s): 
Keyword(s): kbnetwork kbAPI kbSDKPlatform kbNetAPI kbGrpDSNet
Last Modified: 09-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Workstation versions 3.5, 3.51, 4.0 
- Microsoft Windows NT Server versions 3.5, 3.51, 4.0 
- Microsoft Windows 95 
- Microsoft Network Client for MS-DOS version 3.0 
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SUMMARY
=======

There are three types of time sources that must be understood before you set up
the Time Service for your computer running Windows NT.

MORE INFORMATION
================

Top Level Time Source
---------------------

The top level time source represents an accurate time source such as an atomic
clock. The Time Service Initialization file, Timeserv.ini, lists many different
sources for accurate clocks, that is, NISTACTS, USNO, NTP, and so forth.

Primary Source (Masters of Time)
--------------------------------

These computers get their time from a top level time source and are primary time
sources for the other computers on your Local Area Network (LAN). The Type= line
of the Timeserv.ini file should be set to one of the top level time sources in
order to be considered a primary time source. You can have as many Primary
Sources (Masters of Time) as you want on your network, but it is usually
sufficient to just have one.

     Type=USNO

Secondary Source
----------------

These computers have their Type= line set to Primary and the PrimarySource= line
set to one (or more) of the primary sources separated by a semicolon.

     Type=Primary
     PrimarySource=\\NTPDC1;\\NTPDC2...

The secondary sources must have their TimeSource= line set to YES. Setting the
TimeSource=YES actually sets the timesource bit to true that allows down-level
clients to determine who the secondary time sources are. Secondary clients issue
a NetRemoteTOD API call to the primary source to get their time set.

     TimeSource=YES

Clients
-------

Computers running Windows NT can get their time from either a primary source or a
secondary source. If a computer running Windows NT is to get its time from a
primary source, then it sets the Type= line to Primary as explained above.
However, computers running Windows NT can also get their time from a Secondary
Time Source. They do this by setting their Type= line to Secondary.

     Type=Secondary

By default, computers with their type set to Secondary use the NetServerEnum API
call to find servers with the timesource bit set that belong to their own
domain. You can specify a secondary domain with the SecondaryDomain= section of
the Timeserv.ini file.

     SecondaryDomain="Place the workgroup or domain name here."

For computers not running the time service, the same thing happens when they
issue a NET TIME command without any paramaters (it searches its local domain
for a server with its timesource bit set to YES). To get the same function as
the SecondaryDomain, issue a NET TIME /DOMAIN:DOMAINNAME (secondary domain)
command.

Issuing a NET TIME \\SERVER /SET /Y command will cause the down-level client to
set its time with the computer specified whether it is a registered timesource
or not.

NOTE: Because the clients issue a NetServerEnum to enumerate the servers with the
timesource bit set to yes, it will adversely affect the Time Service if browsing
is not working properly on your network.

Additional query words: timeserv time

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Keywords          : kbnetwork kbAPI kbSDKPlatform kbNetAPI kbGrpDSNet 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT351search kbWinNT350search kbWinNT400search kbWinNTW350 kbWinNTW350search kbWinNTW351search kbWinNTW351 kbWinNTSsearch kbWinNTS400search kbWinNTS400 kbWinNTS351 kbWinNTS350 kbWinNTS351search kbWinNTS350search kbAudDeveloper kbWin95search kbZNotKeyword kbZNotKeyword3 kbNetworkClientSearch kbNetworkClient300DOS
Version           : MS-DOS:3.0; Win2000:95; winnt:3.5,3.51,4.0
Hardware          : x86
Issue type        : kbinfo

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