Re: [chrony-users] Minimal online duration
> > Assuming the servers are reachable/fine, would a short connection time of > > 2-3 seconds twice per day be enough to keep synchronized, or should i > > rather enforce some minimum "on" time? (no big precision required, just > > within 1s) > > That should be ok. 1 second per 12 hours is a frequency error of 23 > ppm. Unless the clock on the board is very unstable, its error should > stay well below that. i'm not (so) worried by the precision, but rather if chrony manages to "exploit" in a useful way the single query to each server that it will manage to send in those 2-3 seconds window. There seems to be an implicit "yes" in you answer :) > > server SERVER1/2/3 auto_offline offline iburst presend 10 minpoll 4 > > initstepslew 3600 SERVER1/2/3 > > If you don't need chronyd to block the boot sequence until the clock > is stepped I'd suggest to drop the initstepslew directive ok thanks for the hint! BR, Ariel -- To unsubscribe email chrony-users-requ...@chrony.tuxfamily.org with "unsubscribe" in the subject. For help email chrony-users-requ...@chrony.tuxfamily.org with "help" in the subject. Trouble? Email listmas...@chrony.tuxfamily.org.
Re: [chrony-users] Minimal online duration
On Fri, Feb 09, 2018 at 03:18:08PM +0100, Ariel Garcia wrote: > Assuming the servers are reachable/fine, would a short connection time of > 2-3 seconds twice per day be enough to keep synchronized, or should i rather > enforce some minimum "on" time? (no big precision required, just within 1s) That should be ok. 1 second per 12 hours is a frequency error of 23 ppm. Unless the clock on the board is very unstable, its error should stay well below that. > server SERVER1/2/3 auto_offline offline iburst presend 10 minpoll 4 > initstepslew 3600 SERVER1/2/3 If you don't need chronyd to block the boot sequence until the clock is stepped I'd suggest to drop the initstepslew directive > makestep 3600 2 > fallbackdrift 13 19 > driftfile /var/lib/chrony/sysclock.drift > dumpdir /var/lib/chrony/history > dumponexit That looks ok. -- Miroslav Lichvar -- To unsubscribe email chrony-users-requ...@chrony.tuxfamily.org with "unsubscribe" in the subject. For help email chrony-users-requ...@chrony.tuxfamily.org with "help" in the subject. Trouble? Email listmas...@chrony.tuxfamily.org.
[chrony-users] Minimal online duration
Hello, my use case for chrony is on a device which is connecting for a few seconds every 12 hours to send data. An initial synchronization time on first boot will of course take longer, that's ok. The ppp deamon will set chrony servers online / offline when the link is on/off. Assuming the servers are reachable/fine, would a short connection time of 2-3 seconds twice per day be enough to keep synchronized, or should i rather enforce some minimum "on" time? (no big precision required, just within 1s) Can anybody with a similar use-case comment on experience? My relevant config is: --- server SERVER1/2/3 auto_offline offline iburst presend 10 minpoll 4 initstepslew 3600 SERVER1/2/3 makestep 3600 2 fallbackdrift 13 19 driftfile /var/lib/chrony/sysclock.drift dumpdir /var/lib/chrony/history dumponexit --- Thanks in advance! Ariel -- To unsubscribe email chrony-users-requ...@chrony.tuxfamily.org with "unsubscribe" in the subject. For help email chrony-users-requ...@chrony.tuxfamily.org with "help" in the subject. Trouble? Email listmas...@chrony.tuxfamily.org.