Imported Upstream version 221

[systemd.git] / man / timesyncd.conf.5

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.TH "TIMESYNCD\&.CONF" "5" "" "systemd 221" "timesyncd.conf"
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.SH "NAME"
timesyncd.conf, timesyncd.conf.d \- Network Time Synchronization configuration files
.SH "SYNOPSIS"
.PP
/etc/systemd/timesyncd\&.conf
.PP
/etc/systemd/timesyncd\&.conf\&.d/*\&.conf
.PP
/run/systemd/timesyncd\&.conf\&.d/*\&.conf
.PP
/usr/lib/systemd/timesyncd\&.conf\&.d/*\&.conf
.SH "DESCRIPTION"
.PP
These configuration files control NTP network time synchronization\&.
.SH "CONFIGURATION DIRECTORIES AND PRECEDENCE"
.PP
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\&.
.PP
When packages need to customize the configuration, they can install configuration snippets in
/usr/lib/systemd/*\&.conf\&.d/\&. Files in
/etc/
are reserved for the local administrator, who may use this logic to override the configuration files installed by vendor packages\&. 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 which of the subdirectories they reside in\&. If multiple files specify the same option, the entry in the file with the lexicographically latest name takes precedence\&. 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\&.
.PP
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\&.
.SH "OPTIONS"
.PP
\fINTP=\fR
.RS 4
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
\fBsystemd-networkd.service\fR(8)\&. systemd\-timesyncd will contact all configured system or per\-interface servers in turn until one is found that responds\&. This setting defaults to an empty list\&.
.RE
.PP
\fIFallbackNTP=\fR
.RS 4
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
\fBsystemd-networkd.service\fR(8)
take precedence over this setting, as do any servers set via
\fINTP=\fR
above\&. This setting is hence only used if no other NTP server information is known\&. If this option is not given, a compiled\-in list of NTP servers is used instead\&.
.RE
.SH "SEE ALSO"
.PP
\fBsystemd\fR(1),
\fBsystemd-timesyncd.service\fR(8),
\fBsystemd-networkd.service\fR(8)