Creating a custom time source configuration

NetWare allows you to control what type of time services a NetWare server provides, which time servers a NetWare server contacts for time synchronization, how frequently the server must contact or poll the sources, and how the time adjustments are made.

Use the following procedure to adjust these variables.

The following list describes the prerequesites:

• Access to scoadmin(1M)

• System Owner permission to use scoadmin's NetWare Setup utility

1. From scoadmin, select NetWare, then select the NetWare Setup utility.

2. Select NetWare Server.

3. Select Time Synchronization.

   The ``Time Synchronization Setup'' window appears.

4. Set the following variables as appropriate.

   • Basic. This category shows the most commonly changed time synchronization variables:

     • Time Server Type. This variable specifies how the server synchronizes time (set by the scoadmin Directory Services Install utility): Single, Reference, Primary, or Secondary.

     • Enable Time Service Advertising? This variable controls time source advertising. ``Yes'' means Single Reference, Reference, and Primary time servers advertise; Secondary time servers do not advertise. ``No'' means time servers do not advertise. If it is a time source for other servers, you must add its time to those servers' lists of time sources. The default is ``Yes''.

       We recommend that all servers be configured the same (``Yes'' or ``No'') for this variable to be effective.

     • Directory Tree Mode? This variable controls whether the server synchronizes time with services in its tree and with all servers on the network.

       This variable has no effect if the ``Use Only Configured Sources'' variable is set to ``Yes''.

       When ``Use Only Configured Sources'' is set to ``No'', this variable works as follows:

       • ``Yes'' means the server synchronizes only with services in the Directory tree.

       • ``No'' means the server attempts to synchronize with any time source on the network. With this configuration, make sure any nonproduction servers do not advertise time services.

     • Time Sources. This variable contains the list of time sources this server contacts to determine network time. When the first time source is contacted, the search stops.

     • Use Only Configured Sources? This variable determines which time sources the server listens to. ``Yes'' means servers only listen to the sources in the configured sources list (``Time Sources''). ``No'' means the server first attempts to contact a server listed in the configured sources list; if unsuccessful or the list is empty, the server attempts to contact an advertising time source. The default is ``No''.

   • Advanced. The Advanced category shows and allows you to change less commonly used time synchronization variables:

     • Polling Count. This variable determines the number of time packets to exchange while polling. The default is 3.

     • Polling Interval. This variable determines how often the server checks to see if it is still synchronized with network time. All servers in the Directory tree should use the same value. The interval is specified in seconds, and the maximum is 31 days. The default is 600.

     • Short Interval. When a server discovers it is not synchronized with network time, it starts time synchronization polling at the interval specified by this variable. After synchronization, the polling interval increases until the server is using the value specified by the ``Polling Interval'' variable. The default is 10 seconds.

     • Synchronization Radius. This variable controls the maximum time difference (in milliseconds) a server can differ from network time and still be considered synchronized. Increasing the time allows a greater time difference between servers. Decreasing the time increases the chance of losing server synchronization. When the server is polled, if the time difference is greater, the server is not synchronized. If the time difference is less, the server is synchronized. The default is 2000.

     • Correction Floor. This variable determines how closely servers attempt to synchronize their clocks (in milliseconds). This value cannot exceed the ``Synchronization Radius'' or synchronization may not be achieved. The default is 1.

     • Time Adjustment. This variable determines a single time adjustment in size, date, and time. The format is (+ or -) hour:minute:second at month/day/year hour:minute:second (A.M. or P.M.). If the date and time are not specified, time sources default to six polling intervals or one hour from the current time, whichever is longer. All time sources synchronizing together adjust their clocks by the specified time at the specified date and time.

       Use this variable sparingly to correct network time-wide errors. Misuse of the variable can corrupt time synchronization and the order of events on your network. You cannot use this variable on a second time server. A Reference Time server ignores the adjustments from primary time servers.

5. Click OK.

Example of synchronizing two directory trees

Suppose you have two Directory trees on your network and you want all the servers in both trees to synchronize to the same time.

You used the default installation, so the Root servers of the trees (ROOT1 and ROOT2) are Single Reference servers, Tree Mode is set to ``Yes'', and Service Advertising is set to ``Yes''.

Each Directory tree is synchronized within itself, but time between the Directory trees differs by a few minutes.

To synchronize both trees, stop the NetWare server process on both servers, then set the following variables, and restart the servers.

• Server ROOT1:

  Set ``Time Server Type'' to ``reference''.

  Set ``Time Sources'' to ``root2''

• Server ROOT2:

  Set ``Time Server Type'' to ``primary''

  Set ``Time Sources'' to ``root2''

Since the Roots are now both time providers, it is necessary to change ``Time Server Type'' from ``Single'' to ``Reference'' on Server ROOT1 and ``Primary'' on Server ROOT2.

Server ROOT1 is a Reference server so that there will be a central point for controlling time on the network.

When you synchronize two Directory trees, you double the size of the time synchronization network. You should examine the physical layout of the network and add other Primary servers, or consider hand-configuring the time sources and eliminating the use of SAP.