Re: ajusting clock in steps

Marcus König wrote:

Hello NG,

i compiled ntp version 4.2.0 on AIX 5.1 with a hopf-clock. After that i
compiled this version on AIX 5.2 run as Client for the 5.1. My problem
ist that after a time the clocks are synchronized in one step.

How can I configure the client that he sets the time in steps like 1
second in one hour?

thanks for answering.

regards marcus.


Please see the the ntpd documentation at http://www.eecis.udel.edu/~mills/ntp/html/ntpd.html or it's also available in your ntp-4.2.0.html directory.

In brief, ntpd slews the clock to correct errors less than 128 milliseconds or steps the clock if the error is greater. You can start ntpd with the -x option which will change the threshold to 600 seconds. Doing so, without first setting the clock, will require one full day to correct an error of 42 seconds!!

An error large enough to cause ntpd to step the clock is usually an indication of a problem somewhere.

Best practice is to start ntpd with the -g option which causes ntpd to set the clock on a one time basis. Do so before starting any application that needs either the correct time or monotonically increasing time.

Once started with the correct time, ntpd should be able to maintain the local clock within 5-10 milliseconds of the correct time using internet servers or within 1-2 milliseconds using a server on the LAN.
.

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