August 7, 2010

Synchronize time with external NTP server on Windows Server 2008 R2.

Time synchronization is an important aspect for all computers in a Windows domain. By default, the clients computers get their time from a Domain Controller and the Domain Controller gets his time from the domain’s PDC Operation Master. Therefore the PDC must synchronize his time from an external source. I usually use the servers listed at the NTP Pool Project website. Before you begin, don’t forget to open the default UDP 123 port (in and outbound) on your firewall.

  1. Locate your PDC Server. Open the command prompt and type: C:\>netdom /query fsmo
  2. Log in to your PDC Server and open the command prompt.
  3. Stop the W32Time service: C:\>net stop w32time
  4. Configure the external time sources, type: C:\> w32tm /config /syncfromflags:manual /manualpeerlist:pool.ntp.org
  5. Make your PDC a reliable time source for the clients. Type: C:\>w32tm /config /reliable:yes
  6. Start the w32time service: C:\>net start w32time
  7. The windows time service should begin synchronizing the time. You can check the external NTP servers in the time configuration by typing: C:\>w32tm /query /configuration
  8. Check the Event Viewer for any errors.

Time should now be synchronizing correctly.