Configuring Windows as a NTP (Network Time Protocol) Server
The Windows operating systems from Windows 2000 onwards has an in-built time
synchronization service - Windows Time. The Windows Time service facilitates
a Windows network to provide synchronization of all machines within a domain. This
article describes how to configure the Windows 2000 and Windows 2003 time
service as a NTP server. It shows how to manipulate registry entries to
configure the Windows Time Service.
Before modifying registry entries it is good practice to backup the Windows
registry. This allows the registry to be restored in the event of problems.
Windows 2000 Configuration
Windows 2000 has an integrated time synchronization service, installed by
default, which can synchronize to a NTP Server. Indeed, by manipulating registry
settings, the service can act as both an SNTP client and SNTP server to
synchronize other network clients.
The Windows Time service should be present in the systems service list. The
application executable is w32time.exe. The parameter list for w32time can be
found in the registry at:
Windows 2000 can operate as an NTP client and synchronize to an NTP server by
setting parameter NTP Server to the IP address of a NTP Server.
By default, the Windows 2000 machine will synchronize to the specified NTP
server every 8 hours (or 3 times a day), which may not be enough to maintain
accurate synchronization. The period can be reduced by setting the Period
parameter to how many times a day synchronization is required. Setting the
period to 48 will activate synchronization with the NTP server once every half
hour. Windows 2000 can also be configured to act as an NTP server by setting the
Local NTP parameter to 1.
After editing any of the registry entries for the windows time service, the
service must be restarted for the settings to take effect. The services can be
started or stopped from the service control applet in Administrative Tools.
Alternatively the service can be controlled via the DOS net command thus:
net start w32time net stop w32time
Windows 2003 Configuration
Windows 2003 has expanded on the original Windows 2000 time service by providing
a true NTP implementation. The time service, installed by default, can
synchronize to a NTP Server. Indeed, by manipulating registry settings for the
service it can act as both an NTP server and client to synchronize other network
clients in the domain.