Next: ntpd Description, Previous: (dir), Up: (dir)
The ntpd
program is an operating system daemon that synchronizes the
system clock to remote NTP time servers or local reference clocks.
It is a complete implementation of NTP version 4 defined by RFC-5905, but
also retains compatible with version 3 defined by RFC-1305 and versions
1 and 2, defined by RFC-1059 and RFC-1119, respectively.
The program can operate in any of several modes, including client/server,
symmetric and broadcast modes, and with both symmetric-key and public-key
cryptography.
This document applies to version 4.2.8p10 of ntpd
.
• ntpd Description: | Description | |
• ntpd Invocation: | Invoking ntpd | |
• Usage: | Usage |
The ntpd
program ordinarily requires
a configuration file described at ‘ntp.conf’.
This configuration file contains configuration commands described on
the pages listed above.
However a client can discover remote servers and configure them
automatically.
This makes it possible to deploy a fleet of workstations without
specifying configuration details specific to the local environment.
The ntpd
program normally operates continuously while adjusting the
system time and frequency, but in some cases this might not be
practical.
With the -q
option ntpd
operates as in continuous mode, but
exits just after setting the clock for the first time.
Most applications will probably want to specify the iburst
option with the server
command.
With this option an initial volley of messages is exchanged to
groom the data and set the clock in about ten seconds’ time.
If nothing is heard after a few minutes’ time,
the daemon times out and exits without setting the clock.
Previous: ntpd Description, Up: ntpd Description
What | Default | Flag | Option |
---|---|---|---|
configuration file | /etc/ntp.conf | -c | conffile |
frequency file | none | -f | driftfile |
leapseconds file | none | leapfile | |
process ID file | none | -p | pidfile |
log file | system log | -l | logfile |
include file | none | none | includefile |
statistics path | /var/NTP | -s | statsdir |
keys path | /usr/local/etc | -k | keysdir |