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RDATE(8) System Manager's Manual RDATE(8)

rdateset the system's date from a remote host

rdate [-46acnopsv] host

rdate displays and sets the local date and time from the host name or address given as the argument. The time source may be an RFC 5905 protocol SNTP/NTP server or an RFC 868 TCP protocol server, which is usually implemented as a built-in service of inetd(8). By default, rdate uses the RFC 5905 SNTP/NTP protocol.

The options are as follows:

Forces rdate to use IPv4 addresses only.
Forces rdate to use IPv6 addresses only.
Use the adjtime(2) call to gradually skew the local time to the remote time rather than just hopping.
Correct leap seconds. This should be used only when synchronizing to a server which does not correctly account for leap seconds.
Use SNTP (RFC 5905) instead of the RFC 868 time protocol. This is the default. This protocol counts 32 bits of seconds from January 1, 1900 and will rollover in March 2036.
Use an RFC 868 TCP protocol server instead of SNTP. This protocol is obsolete as it is not capable of representing dates past January 19, 2038 03:14:07 GMT.
Do not set, just print the remote time.
Do not print the time.
Verbose output. Always show the adjustment.

record of date resets and time changes

To get the legal time in Germany, set the /etc/localtime symlink to /usr/share/zoneinfo/right/Europe/Berlin and issue the following command:

# rdate -v

The command of course assumes you have a working internet connection and DNS set up to connect to the server at in Braunschweig, Germany.

date(1), adjtime(2), inetd(8), ntpd(8)

February 10, 2015 OpenBSD-5.9