timesyncd.conf(5) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | CONFIGURATION DIRECTORIES AND PRECEDENCE | OPTIONS | SEE ALSO | COLOPHON

TIMESYNCD.CONF(5)            timesyncd.conf            TIMESYNCD.CONF(5)

NAME         top

       timesyncd.conf, timesyncd.conf.d - Network Time Synchronization
       configuration files

SYNOPSIS         top

       /etc/systemd/timesyncd.conf

       /etc/systemd/timesyncd.conf.d/*.conf

       /run/systemd/timesyncd.conf.d/*.conf

       /usr/lib/systemd/timesyncd.conf.d/*.conf

DESCRIPTION         top

       These configuration files control NTP network time
       synchronization. See systemd.syntax(7) for a general description
       of the syntax.

CONFIGURATION DIRECTORIES AND PRECEDENCE         top

       The default configuration is defined during compilation, so a
       configuration file is only needed when it is necessary to deviate
       from those defaults. By default, the configuration file in
       /etc/systemd/ contains commented out entries showing the defaults
       as a guide to the administrator. This file can be edited to
       create local overrides.

       When packages need to customize the configuration, they can
       install configuration snippets in /usr/lib/systemd/*.conf.d/ or
       /usr/local/lib/systemd/*.conf.d/. The main configuration file is
       read before any of the configuration directories, and has the
       lowest precedence; entries in a file in any configuration
       directory override entries in the single configuration file.
       Files in the *.conf.d/ configuration subdirectories are sorted by
       their filename in lexicographic order, regardless of in which of
       the subdirectories they reside. When multiple files specify the
       same option, for options which accept just a single value, the
       entry in the file with the lexicographically latest name takes
       precedence. For options which accept a list of values, entries
       are collected as they occur in files sorted lexicographically.

       Files in /etc/ are reserved for the local administrator, who may
       use this logic to override the configuration files installed by
       vendor packages. It is recommended to prefix all filenames in
       those subdirectories with a two-digit number and a dash, to
       simplify the ordering of the files.

       To disable a configuration file supplied by the vendor, the
       recommended way is to place a symlink to /dev/null in the
       configuration directory in /etc/, with the same filename as the
       vendor configuration file.

OPTIONS         top

       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.service(8). 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.service(8) 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.

       ConnectionRetrySec=
           Specifies the delaying attempts to contact servers after
           network is online. Takes a time value (in seconds). Defaults
           to 30 seconds and must not be smaller than 1 seconds.

SEE ALSO         top

       systemd(1), systemd-timesyncd.service(8),
       systemd-networkd.service(8)

COLOPHON         top

       This page is part of the systemd (systemd system and service
       manager) project.  Information about the project can be found at
       ⟨http://www.freedesktop.org/wiki/Software/systemd⟩.  If you have
       a bug report for this manual page, see
       ⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.
       This page was obtained from the project's upstream Git repository
       ⟨https://github.com/systemd/systemd.git⟩ on 2020-12-18.  (At that
       time, the date of the most recent commit that was found in the
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       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

systemd 247                                            TIMESYNCD.CONF(5)

Pages that refer to this page: systemd.directives(7)systemd.index(7)systemd.syntax(7)systemd-timesyncd.service(8)