TIMED(8)                386BSD System Manager's Manual                TIMED(8)

NAME
     timed - time server daemon

SYNOPSIS
     timed [-M] [-t] [-i network] [-n network]

DESCRIPTION
     This is the time server daemon and is normally invoked at boot time from
     the rc(8) file.  It synchronizes the host's time with the time of other
     machines in a local area network running timed 8. These time servers will
     slow down the clocks of some machines and speed up the clocks of others
     to bring them to the average network time.  The average network time is
     computed from measurements of clock differences using the ICMP timestamp
     request message.

     The service provided by timed is based  on a master-slave scheme.  When
     timed 8 is started on a machine, it asks the master for the network time
     and sets the host's clock to that time.  After that, it accepts
     synchronization messages periodically sent by the master and calls
     adjtime(2) to perform the needed corrections on the host's clock.

     It also communicates with date(1) in order to set the date globally, and
     with timedc(8),  a timed control program.  If the machine running the
     master crashes, then the slaves will elect a new master from among slaves
     running with the -M flag.  A timed running without the -M flag will
     remain a slave.  The -t flag enables timed to trace the messages it
     receives in the file /var/log/timed.log. Tracing can be turned on or off
     by the program timedc(8).  Normally timed checks for a master time server
     on each network to which it is connected, except as modified by the
     options described below.  It will request synchronization service from
     the first master server located.  If permitted by the -M flag, it will
     provide synchronization service on any attached networks on which no
     current master server was detected.  Such a server propagates the time
     computed by the top-level master.  The -n flag, followed by the name of a
     network which the host is connected to (see networks(5)),  overrides the
     default choice of the network addresses made by the program.  Each time
     the -n flag appears, that network name is added to a list of valid
     networks.  All other networks are ignored.  The -i flag, followed by the
     name of a network to which the host is connected (see networks(5)),
     overrides the default choice of the network addresses made by the
     program.  Each time the -i flag appears, that network name is added to a
     list of networks to ignore.  All other networks are used by the time
     daemon.  The -n and -i flags are meaningless if used together.

FILES
     /var/log/timed.log        tracing file for timed
     /var/log/timed.masterlog  log file for master timed

SEE ALSO
     date(1),  adjtime(2),  gettimeofday(2),  icmp(4),  timedc(8),

     R. Gusella, and S. Zatti, TSP: The Time Synchronization Protocol for UNIX
     4.3BSD.

HISTORY
     The timed daemon appeared in 4.3BSD.

4.3 Berkeley Distribution       April 27, 1991                               1