On our Ubuntu 20.04 servers we run chrony as a time service. Unfortunately we always have time synchronization problems. It would be great if it ran always correctly for up to 0.05 seconds.
How can we fix this? What has to be switched off? How can you set chrony so that no problems arise? We have the standard configuration.
In addition, it would be nice if someone could say what I can check to find out why chrony can't synchronise sometimes:
systemctl status chrony
● chrony.service - chrony, an NTP client/server
Loaded: loaded (/lib/systemd/system/chrony.service; enabled; vendor preset: enabled)
Active: active (running) since Fri 2020-11-13 08:33:58 CET; 3 weeks 3 days ago
Docs: man:chronyd(8)
man:chronyc(1)
man:chrony.conf(5)
Main PID: 825 (chronyd)
Tasks: 2 (limit: 2282)
Memory: 2.0M
CGroup: /system.slice/chrony.service
├─825 /usr/sbin/chronyd -F -1
└─826 /usr/sbin/chronyd -F -1
Nov 13 08:33:58 server systemd[1]: Starting chrony, an NTP client/server...
Nov 13 08:33:58 server chronyd[825]: chronyd version 3.5 starting (+CMDMON +NTP +REFCLOCK +RTC +PRIVDROP +SCFILTER +SIGND +ASYNCDNS +SECHASH +IPV6 >
Nov 13 08:33:58 server chronyd[825]: Frequency -39.027 +/- 0.054 ppm read from /var/lib/chrony/chrony.drift
Nov 13 08:33:58 server chronyd[825]: Loaded seccomp filter
Nov 13 08:33:58 server systemd[1]: Started chrony, an NTP client/server.
Nov 13 08:34:02 server chronyd[825]: Selected source NTP Server IP
Nov 23 07:41:33 server chronyd[825]: Can't synchronise: no selectable sources
Nov 23 08:14:56 server chronyd[825]: Selected source NTP Server IP
Thanks in advance.