chronyd

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.conf.

Documentation

• man 8 'chronyd' [EN]

Installation & Configuration

Files

• /
  • etc/
    • chrony.conf, Example: 1
    • sysconfig/ (Used in Red Hat Enterprise Linux & Fedora)
      • chronyd, Example: 1

Syntax

chronyd [PARAMETER ...]

Parameters

-4

With this option hostnames will be resolved only to IPv4 addresses and only IPv4 sockets will be created.

-6

With this option hostnames will be resolved only to IPv6 addresses and only IPv6 sockets will be created.

-f FILE

This option can be used to specify an alternate location for the configuration FILE (default /etc/chrony.conf).

-q

When run in this mode, chronyd will set the system clock once and exit. It will not detach from the terminal.