[ntp:questions] Default config on Ubuntu doesn't work as client

Maarten Wiltink maarten at kittensandcats.net
Tue Mar 11 09:20:33 UTC 2008


"Michael B Allen" <miallen at ioplex.com> wrote in message
news:20080310183745.2979d85d.miallen at ioplex.com...

> [...] Could the fact that Ubuntu is running in VMWare Server be a problem?

Yes. Very much so. Install the VMWare tools and let the virtual machine
host control the passage of time on the clients. Only run NTP on the
host machine.

There's a whitepaper somewhere. It boils down to 'Virtual machines are
not suited to real-time software. Let the host control time, it will
do a better job.'

Time synchronisation in the clients is off by default, and they _will_
drift. I have two old Linux machines now virtualised, both without VMWare
tools installed. With adjtimex I managed to get one below 1PPM and it
now steps half a second each week; for the other one (kernel 2.0) I
didn't find or compile an adjtimex yet and it steps 2.5 seconds each
day.

Groetjes,
Maarten Wiltink





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