TIMED(8)						      System Manager'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  net-
       work  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  /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 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

       /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

4.3 Berkeley Distribution					 November 17, 1996							  TIMED(8)