linuxptp-users

[Linuxptp-users] PHC2SYS clock jumped forward or running faster than expected

[Jord P. <jor...@ou...>]

Hi all,


I am running a phc2sys instance which is synchronising the system clock to the physical hardware clock and is running with perfect offset values. However once every 20 minutes it returns the message "clock jumped forward or running faster than expected" with a sudden offset of 0,9 second which immediately recovers to normal values within 10 seconds.


However, I can not permit to have a nearly 1 second offset for a short amount of time every 20 seconds. What could be the cause or solution to this?


Jord Pool
IT Service Management

Re: [Linuxptp-users] PHC2SYS clock jumped forward or running faster than expected

[Miroslav L. <mli...@re...>]

On Mon, May 14, 2018 at 08:49:47AM +0000, Jord Pool wrote:
> However, I can not permit to have a nearly 1 second offset for a short amount of time every 20 seconds. What could be the cause or solution to this?

The first suspect would be an NTP client. Are you sure there is no
systemd-timesyncd, ntpd, chronyd, openntpd, or similar running?

-- 
Miroslav Lichvar

Re: [Linuxptp-users] PHC2SYS clock jumped forward or running faster than expected

[Jord P. <jor...@ou...>]

When running '# systemctl status ntp' it indeed seemed that NTP was 'active'. I have now disabled NTP by running '# systemctl stop ntp'. Will let it run and see if this helps!


Thank you!


Jord Pool
IT Service Management


________________________________
From: Miroslav Lichvar <mli...@re...>
Sent: Monday, May 14, 2018 10:56:18 AM
To: Jord Pool
Cc: lin...@li...
Subject: Re: [Linuxptp-users] PHC2SYS clock jumped forward or running faster than expected

On Mon, May 14, 2018 at 08:49:47AM +0000, Jord Pool wrote:
> However, I can not permit to have a nearly 1 second offset for a short amount of time every 20 seconds. What could be the cause or solution to this?

The first suspect would be an NTP client. Are you sure there is no
systemd-timesyncd, ntpd, chronyd, openntpd, or similar running?

--
Miroslav Lichvar