2.11BSD#431 - /usr/man/cat8/timed.0

TIMED(8)	    UNIX Programmer's Manual		 TIMED(8)


NAME
     timed - time server daemon

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

DESCRIPTION
     Timed 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 per-
     form 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  /usr/adm/timed.log.	 Tracing  can  be
     turned  on  or off by the program timedc(8).  Timed normally
     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 net-
     works  on which no current master server was detected.  Such
     a server propagates the time computed by the top-level  mas-
     ter.   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.


Printed 11/26/99	November 17, 1996			1


TIMED(8)	    UNIX Programmer's Manual		 TIMED(8)


FILES
     /usr/adm/timed.log           tracing file for timed
     /usr/adm/timed.masterlog	  log file for master timed

SEE ALSO
     date(1), adjtime(2), gettimeofday(2), icmp(4P), timedc(8),
     TSP: The Time Synchronization Protocol for UNIX  4.3BSD,  R.
     Gusella and S. Zatti


Printed 11/26/99	November 17, 1996			2