Suppose you have server A and server B. Server B is running 60 seconds too fast, while server A is accurate. Is there a way to gradually move server B's time back into sync with server A, without making a drastic, immediate change to the clock? In other words, we would like to 'smear' the difference across several hours or days to ensure there are no drastic changes in timestamps, etc.
On Tue, Sep 4, 2012 at 12:17 PM, Sean Carolan scarolan@gmail.com wrote:
Suppose you have server A and server B. Server B is running 60 seconds too fast, while server A is accurate. Is there a way to gradually move server B's time back into sync with server A, without making a drastic, immediate change to the clock? In other words, we would like to 'smear' the difference across several hours or days to ensure there are no drastic changes in timestamps, etc.
This is already how ntpd works. When you first start the service (usually upon reboot), it will use 'ntpdate' to do a hard set of the clock, then ntpd picks up and adjusts the clock back and forth to keep it correct.
❧ Brian Mathis
This is already how ntpd works. When you first start the service (usually upon reboot), it will use 'ntpdate' to do a hard set of the clock, then ntpd picks up and adjusts the clock back and forth to keep it correct.
My understanding was that ntpd will use "slewing" for adjustments of less than ~120ms or so, but for adjustments between 120ms and 17 minutes it will use "stepping" instead, making an abrupt and immediate adjustment of the entire delta.
What I'm trying to avoid is abruptly resetting the clock from 12:06 to 12:05 all at once. Instead we want to slowly turn the clock back that one minute, but spread the changes across several hours or days.
What I'm trying to avoid is abruptly resetting the clock from 12:06 to 12:05 all at once. Instead we want to slowly turn the clock back that one minute, but spread the changes across several hours or days.
I think the "-x" option may be our solution; I R'd the FM and it says:
"...If the -x option is included on the command line, the clock will never be stepped and only slew corrections will be used."
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Brian Mathis -
Sean Carolan