OSF DCE Administration Guide--Core Components

OSF DCE Administration Guide—Core Components

In order to use the clock set command effectively, you must have temporary access to an

accurate time reference. Such references can include the time signals that many

standards organizations disseminate by radio or telephone. You can also use a clock that

you have recently veriﬁed as accurate. (See Appendix C for a list of time reference

sources.)

Because it is a manually entered command that is used to modify an absolute time, the

clock set command is not useful for small inaccuracy settings. The minimum reliable

inaccuracy that you can achieve with the command is approximately 1 second. Human

error and processing delays combine to make lower settings unreliable. For example,

you enter the command and new time and then begin monitoring the reference. When

you perceive that the reference has reached the desired time, you press <Return> to

initiate the command. Your perception of the reference mark and your pressing of

<Return> do not exactly coincide. Furthermore, once the command is initiated, DTS

takes time to interpret and execute the command.

The following example shows how to change both the time and epoch for a system:

dcecp> clock set 1993-10-07-09:30:15.0000I01.0000 -abruptly -epoch 1

25.7.3 Forcing System Synchronization

Once you create and enable DTS on all the systems that are in your network, they

synchronize without any further intervention. There are situations, however, when you

may want to force a system to synchronize immediately rather than waiting for the

amount of time that is speciﬁed by the syncinterval and maxinaccuracy attributes. As

an example, you may want to synchronize a system with a TP server that you have just

added to the network.

To forcibly synchronize the clock on a system, you use the dts synchronize command.

If you enter the dts synchronize command without the optional -abruptly option, the

time is adjusted gradually. If you enter the dts synchronize command with the

-abruptly option, the time is immediately adjusted. In the situation posed by our

example, you might want to use the command with the -abruptly option to have the

narrow time interval contributed by the time-provider quickly propagated throughout the

network:

dcecp> dts synchronize -abruptly

25.8 Controlling Access to DTS

You can assign privileges that control access to DTS objects by using DCE

Authorization Service access control lists (ACLs).

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