TIMESYNC(8) TIMESYNC(8)
NAME
timesync - synchronize the system clock to a time source
SYNOPSIS
aux/timesync [ -a accuracy ] [ -S stratum ] [ -s netroot ] [
-frnDdLilG ] [ timeserver ]
DESCRIPTION
Aux/timesync synchronizes the system clock to a time source,
by default a file server. The options are:
-f synchronize to a file server. If timeserver is missing,
use /srv/boot.
-r synchronize to the local real time clock, #r/rtc.
-L used with -r to indicate the real time clock is in local
time rather than GMT. This is useful on PCs that also
run the Windows OS.
-n synchronize to an NTP server. If timeserver is missing,
dial the server udp!$ntp!ntp.
-D print debugging to standard error
-d put file containing last determined clock frequency in
directory dir, default /tmp.
-i stands for impotent. Timesync announces what it would
do but doesn't do it. This is useful for tracking
alternate time sources.
-a specifies the accuracy in nanoseconds to which the clock
should be synchronized. This determines how often the
reference clock is accessed.
-G causes timesync to use a gps server (see gpsfs(8)) as a
time source.
-s causes timesync to listen for UDP NTP requests on the
network rooted at netroot. Up to 4 -s options are
allowed.
-S sets the stratum number to stratum.
-l turns on logging to /sys/log/timesync.
FILES
/tmp/ts.<sysname>.<type>.timeserver where the last
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TIMESYNC(8) TIMESYNC(8)
frequency guess is kept
/sys/log/timesync log file
SOURCE
/sys/src/cmd/aux/timesync.c
BUGS
Only works with IPv4.
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