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Entry  Mon Aug 16 23:30:34 2021, Paco, Update, CDS, AS WFS commissioning; restarting models 
    Reply  Thu Aug 19 03:23:00 2021, Anchal, Update, CDS, Time synchornization not running 
       Reply  Thu Aug 19 14:14:49 2021, Koji, Update, CDS, Time synchornization not running 
          Reply  Fri Aug 20 00:28:55 2021, Anchal, Update, CDS, Time synchornization not running 
             Reply  Fri Aug 20 06:24:18 2021, Anchal, Update, CDS, Time synchornization not running 
Message ID: 16283     Entry time: Thu Aug 19 03:23:00 2021     In reply to: 16280     Reply to this: 16284
Author: Anchal 
Type: Update 
Category: CDS 
Subject: Time synchornization not running 

I tried to read a bit and understand the NTP synchronization implementation in FE computers. I'm quite sure that NTP synchronization should be 'yes' if timesyncd are running correctly in the output of timedatectl in these computers. As Koji reported in 15791, this is not the case. I logged into c1lsc, c1sus and c1ioo and saw that RTC has drifted from the software clocks too which does not happen if NTP synchronization was active. This would mean that almost certainly, if the computers are rebooted, the synchronization will be lost and the models will fail to come online.

My current findings are the following (this should be documented in wiki once we setup everything):

  • nodus is running a NTP server using chronyd. One can check the configuration of this NTP serer in /etc/chornyd.conf
  • fb1 is running an NTP server using ntpd that follows nodus and an IP address 131.215.239.14. This can be seen in /etc/ntp.conf.
  • There are no comments to describe what this other server (131.215.239.14) is. Does the GC network have an NTP server too?
  • c1lsc, c1sus and c1ioo all have systemd-timesyncd.service running with configuration file in /etc/systemd/timesyncd.conf.
  • The configuration file set Servers=ntpserver but echo $ntpserver produces nothing (blank) on these computers and I've been unable to find anyplace where ntpserver is defined.
  • In chiara (our name server), the name server file /etc/hosts does not have any entry for ntpserver either.
  • I think the problem might be that these computers are unable to find the ntpserver as it is not defined anywhere.

The solution to this issue could be as simple as just defining ntpserver in the name server list. But I'm not sure if my understanding of this issue is correct. Comments/suggestions are welcome for future steps.

 

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