systemd timesyncd.conf 5 timesyncd.conf timesyncd.conf.d Network Time Synchronization configuration files /etc/systemd/timesyncd.conf /etc/systemd/timesyncd.conf.d/*.conf /run/systemd/timesyncd.conf.d/*.conf /usr/lib/systemd/timesyncd.conf.d/*.conf These configuration files control NTP network time synchronization. See systemd.syntax5 for a general description of the syntax. The following settings are configured in the [Time] section: NTP= A space-separated list of NTP server host names or IP addresses. During runtime this list is combined with any per-interface NTP servers acquired from systemd-networkd.service8. systemd-timesyncd will contact all configured system or per-interface servers in turn until one is found that responds. When the empty string is assigned, the list of NTP servers is reset, and all assignments prior to this one will have no effect. This setting defaults to an empty list. FallbackNTP= A space-separated list of NTP server host names or IP addresses to be used as the fallback NTP servers. Any per-interface NTP servers obtained from systemd-networkd.service8 take precedence over this setting, as do any servers set via NTP= above. This setting is hence only used if no other NTP server information is known. When the empty string is assigned, the list of NTP servers is reset, and all assignments prior to this one will have no effect. If this option is not given, a compiled-in list of NTP servers is used instead. RootDistanceMaxSec= Maximum acceptable root distance. Takes a time value (in seconds). Defaults to 5 seconds. PollIntervalMinSec= PollIntervalMaxSec= The minimum and maximum poll intervals for NTP messages. Each setting takes a time value (in seconds). PollIntervalMinSec= must not be smaller than 16 seconds. PollIntervalMaxSec= must be larger than PollIntervalMinSec=. PollIntervalMinSec= defaults to 32 seconds, and PollIntervalMaxSec= defaults to 2048 seconds. systemd1, systemd-timesyncd.service8, systemd-networkd.service8