- stretch 3.0-4+deb9u2
- testing 3.4-4
- unstable 3.4-4
- experimental 3.5-1
CHRONYD(8) | System Administration | CHRONYD(8) |
NAME¶
chronyd - chrony daemonSYNOPSIS¶
chronyd [OPTION]... [DIRECTIVE]...DESCRIPTION¶
chronyd is a daemon for synchronisation of the system clock. It can synchronise the clock with NTP servers, reference clocks (e.g. a GPS receiver), and manual input using wristwatch and keyboard via chronyc. It can also operate as an NTPv4 (RFC 5905) server and peer to provide a time service to other computers in the network.If no configuration directives are specified on the command line, chronyd will read them from a configuration file. The compiled-in default location of the file is /etc/chrony/chrony.conf.
Information messages and warnings will be logged to syslog.
OPTIONS¶
-4-6
-f file
-n
-d
-q
-Q
-r
-R
-s
If used in conjunction with the -r flag, chronyd will attempt to preserve the old samples after setting the system clock from the RTC. This can be used to allow chronyd to perform long term averaging of the gain or loss rate across system reboots, and is useful for systems with intermittent access to network that are shut down when not in use. For this to work well, it relies on chronyd having been able to determine accurate statistics for the difference between the RTC and system clock last time the computer was on.
If the last modification time of the drift file is later than both the current time and the RTC time, the system time will be set to it to restore the time when chronyd was previously stopped. This is useful on computers that have no RTC or the RTC is broken (e.g. it has no battery).
-t timeout
-u user
On Linux, chronyd needs to be compiled with support for the libcap library. On macOS, FreeBSD, NetBSD and Solaris chronyd forks into two processes. The child process retains root privileges, but can only perform a very limited range of privileged system calls on behalf of the parent.
-F level
It’s recommended to enable the filter only when it’s known to work on the version of the system where chrony is installed as the filter needs to allow also system calls made from libraries that chronyd is using (e.g. libc) and different versions or implementations of the libraries may make different system calls. If the filter is missing some system call, chronyd could be killed even in normal operation.
-P priority
-m
-v
FILES¶
/etc/chrony/chrony.confSEE ALSO¶
chronyc(1), chrony.conf(5)BUGS¶
For instructions on how to report bugs, please visit ⟨URL: https://chrony.tuxfamily.org/ ⟩.AUTHORS¶
chrony was written by Richard Curnow, Miroslav Lichvar, and others.2017-01-12 | chrony 3.0 |