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Synchronizing your Computer's Clock with Penn's Network Time Server in Mac OS X

To synchronize your computer's clock with Penn's network time server

Kerberos requires that your Macintosh clock be in sync with that of the Kerberos KDC (ticket-dispensing) server. You can synchronize your computer's clock with Penn's network time server to ensure that your computer's date and time remain consistent with that of the Kerberos server.

  1. From the Apple Menu, open the System Preferences window.

  2. Click the Date & Time icon in the System section of the window.

  3. In the Date & Time window, click the Network Time tab.

  4. Click to activate the Use a network time server checkbox, if not already checked.

  5. In the "NTP Server" field, type "timeserver1.upenn.edu", then click the Set Time Now button.
    After you click the button, a status message will appear:

    • "Synchronization Succeeded"

    • "Synchronization Failed. Your NTP Server may not be responding."
      If you receive this message, you may wish to check your spelling in the "NTP Server" field, or select a different Penn network time server. After adjusting your server settings, click the "Set Time Now" button again.

  6. Optional: To freeze your settings, click the lock icon in the lower left corner, captioned as "Click the lock to prevent further changes."
  7. Close the Date & Time window.

    Note
    : Penn has 3 time servers. You can use any of these servers to synchronize time. Below is a list of the Penn time servers:
  • timeserver1.upenn.edu
  • timeserver2.upenn.edu
  • timeserver3.upenn.edu

To select the proper local time zone for your computer:

Once you have synchronized your computer's clock, if it still differs widely from your local time, check to determine whether you have set the time zone correctly.

  1. From the Apple Menu, open the System Preferences window.

  2. Click the Date & Time icon in the System section of the window.

  3. In the Date & Time window, click the Time Zone tab.

  4. As noted above the world map, "Click your part of the world and then choose a time zone from the pop-up menu."
    For example, users in Philadelphia would click the eastern region of the United States, then select "U.S.A.-Eastern" from the resulting pop-up menu.

  5. Close the Date & Time window.

To change the local time zone:

If you have transported your computer to another time zone and want to display the new local time, you must change the time zone designation, not the time display itself, in order to maintain proper synchronization with the network time server.

Note: Do not attempt to manually adjust either the Current Date or Current Time fields. They will be automatically and correctly reset by steps below.

If you have already chosen to synchronize with a network time server, the system will bar you from resetting the date or time by hand.

  1. From the Apple Menu, open the System Preferences window.

  2. Click the Date & Time icon in the System section of the window.

  3. In the Date & Time window, click the Time Zone tab.

  4. As noted above the world map, "Click your part of the world and then choose a time zone from the pop-up menu."
    For example, users in Liverpool, England would click "United Kingdom" from the resulting pop-up menu.

  5. Close the Date & Time window.

 

Information Systems and Computing
University of Pennsylvania
Information Systems and Computing, University of Pennsylvania