On 2009-03-10, Mike K Smith <[email protected]> wrote: >Steve Kostecke wrote: > >>Mike K Smith <[email protected]> wrote: >> >>> For testing purposes I want to configure an NTP server to run with >>> a small but known offset. I would like to test at the following >>> offset values 25, 90, 180, 350 and 2500ms. >> >> What is this test intended to prove? > > I want to understand how long it takes in practice for an offset to be > propagated from stratum 1 servers through a set of stratum 2 servers > to a stratum 3 client.
[snip] >>> with a fudge line to set the time1 parameter to 90ms. >> >>> The server showed a 90ms offset after the first poll of the local >>> clock, but within a few poll cycles it had discarded the offset. >> >> That's because ntpd disciplined the clock to amortize that offset. >> >> Once this has happened, the clock is now operating at the 90ms offset. >> >> Isn't this what you wanted? > > What you describe is what I expected. What I wanted was for that > offset to be reflected in the time output by the ntpd. Now that I thing about it, what happened when you applied that offset is that you "moved" the clock 90ms. > What I saw was a very slow slew, which generated about 3ms offset in > an hour - this is just under 1ppm which I would expect from a free- > running local clock which has a fairly current drift correction.. The place to see view offset is from the client. Is that where you were looking from? -- Steve Kostecke <[email protected]> NTP Public Services Project - http://support.ntp.org/ _______________________________________________ questions mailing list [email protected] https://lists.ntp.org/mailman/listinfo/questions
