— set the
system's date from a remote host
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 868 TCP protocol server, which is usually implemented as a built-in
service of inetd(8)
, or an RFC 2030 protocol
SNTP/NTP server. By default, rdate
uses the RFC
868 TCP protocol.
The options are as follows:
- Forces rdate to use IPv4
- Forces rdate to use IPv6
- Use the adjtime(2) call to
gradually skew the local time to the remote time rather than just
- Correct leap seconds. Sometimes required when synchronizing
to an NTP server. When synchronizing using the RFC 868 protocol, use this
option only if the server does not correctly account for leap seconds. You
can determine if you need this parameter if you sync against an NTP server
(with this parameter) or (recommended) check with a local radio controlled
watch or phone service.
- Use SNTP (RFC 2030) instead of the RFC 868 time
- Use port port instead of
- Do not set, just print the remote time.
- Do not print the time.
- Use UDP instead of TCP as transport.
- Verbose output. Always show the adjustment.
- record of date resets and time changes
To get the legal time in Germany, set the
the following command:
# rdate -ncv ptbtime1.ptb.de
The command of course assumes you have a working internet connection and DNS set
up to connect to the server at
To gradually adjust time once an hour after the first “step”
adjustment, put the following line into root's crontab:
58 * * * * rdate -ncav ptbtime1.ptb.de | logger
To to set the time through an ssh tunnel, use something like so:
ssh -f -L 10037:time.example.com:37
tyr.example.com sleep 10
rdate -a -o 10037 locahost
This manual page was written by Christos
It was changed by
Anibal Monsalve Salazar
for the Debian