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NTPDC(8)		     System Manager's Manual			NTPDC(8)

NAME
     ntpdc -- vendor-specific NTPD control program

SYNOPSIS
     ntpdc [-flags] [-flag [value]] [--option-name[[=| ]value]] [ host ...]

DESCRIPTION
     ntpdc  is	deprecated.   Please  use  ntpq(8)instead - it can do everything
     ntpdc used to do, and it does so using a much more sane interface.

     ntpdc is a utility program used to query ntpd(8) about  its  current  state
     and  to  request changes in that state.  It uses NTP mode 7 control message
     formats described in the source code.  The program may be run either in in-
     teractive mode or controlled using command line arguments.  Extensive state
     and statistics information is available through the  ntpdc  interface.   In
     addition,	nearly	all  the configuration options which can be specified at
     startup using ntpd's configuration file may also be specified at  run  time
     using ntpdc.

OPTIONS
     -4, --ipv4
	     Force  IPv4  DNS  name  resolution.  This option must not appear in
	     combination with any of the following options: ipv6.

	     Force DNS resolution of following host names on the command line to
	     the IPv4 namespace.

     -6, --ipv6
	     Force IPv6 DNS name resolution.  This option  must  not  appear  in
	     combination with any of the following options: ipv4.

	     Force DNS resolution of following host names on the command line to
	     the IPv6 namespace.

     -c cmd, --command=cmd
	     run a command and exit.  This option may appear an unlimited number
	     of times.

	     The following argument is interpreted as an interactive format com-
	     mand  and	is  added  to the list of commands to be executed on the
	     specified host(s).

     -d, --debug-level
	     Increase debug verbosity level.  This option may appear  an  unlim-
	     ited number of times.

     -D number, --set-debug-level=number
	     Set the debug verbosity level.  This option may appear an unlimited
	     number  of times.	This option takes an integer number as its argu-
	     ment.

     -i, --interactive
	     Force ntpq to operate in interactive mode.  This  option  must  not
	     appear  in  combination with any of the following options: command,
	     listpeers, peers, showpeers.

	     Force ntpq to operate in interactive mode.  Prompts will be written
	     to the standard output and commands read from the standard input.

     -l, --listpeers
	     Print a list of the peers.  This option must not appear in combina-
	     tion with any of the following options: command.

	     Print a list of the peers known to the server as well as a  summary
	     of  their	state. This is equivalent to the 'listpeers' interactive
	     command.

     -n, --numeric
	     numeric host addresses.

	     Output all host addresses in dotted-quad numeric format rather than
	     converting to the canonical host names.

     -p, --peers
	     Print a list of the peers.  This option must not appear in combina-
	     tion with any of the following options: command.

	     Print a list of the peers known to the server as well as a  summary
	     of  their state. This is equivalent to the 'peers' interactive com-
	     mand.

     -s, --showpeers
	     Show a list of the peers.	This option must not appear in	combina-
	     tion with any of the following options: command.

	     Print  a list of the peers known to the server as well as a summary
	     of their state. This is equivalent  to  the  'dmpeers'  interactive
	     command.

     -u, --unconnected
	     Use unconnected UDP to communicate with ntpd (default on Windows).

	     Open  an  unconnected  UDP association to ntpd (the default on Win-
	     dows).

     -?, --help
	     Display usage information and exit.

     -!, --more-help
	     Pass the extended usage information through a pager.

     -> [cfgfile], --save-opts [=cfgfile]
	     Save the option state to cfgfile.	The default is the last configu-
	     ration file listed in the OPTION PRESETS section, below.  The  com-
	     mand will exit after updating the config file.

     -< cfgfile, --load-opts=cfgfile, --no-load-opts
	     Load  options from cfgfile.  The no-load-opts form will disable the
	     loading of earlier config/rc/ini files.  --no-load-opts is  handled
	     early, out of order.

     --version [{v|c|n}]
	     Output  version  of  program  and exit.  The default mode is `v', a
	     simple version.  The `c' mode will print copyright information  and
	     `n' will print the full copyright notice.

OPTION PRESETS
     Any  option  that is not marked as not presettable may be preset by loading
     values from configuration ("RC" or ".INI") file(s) and values from environ-
     ment variables named:
       NTPDC_<option-name> or NTPDC
     The environmental presets take precedence (are processed  later  than)  the
     configuration  files.   The  homerc  files are "$HOME", and ".".  If any of
     these are directories, then the file .ntprc is searched  for  within  those
     directories.

USAGE
     If  one or more request options are included on the command line when ntpdc
     is executed, each of the requests will be sent to the NTP	servers  running
     on  each  of  the hosts given as command line arguments, or on localhost by
     default.  If no request options are given, ntpdc will attempt to read  com-
     mands  from  the standard input and execute these on the NTP server running
     on the first host given on the command line, again defaulting to  localhost
     when  no  other  host is specified.  The ntpdc utility will prompt for com-
     mands if the standard input is a terminal device.

     The ntpdc utility uses NTP mode 7	packets  to  communicate  with	the  NTP
     server, and hence can be used to query any compatible server on the network
     which permits it.	Note that since NTP is a UDP protocol this communication
     will  be  somewhat  unreliable, especially over large distances in terms of
     network topology.	The ntpdc utility makes no  attempt  to  retransmit  re-
     quests,  and  will  time  requests out if the remote host is not heard from
     within a suitable timeout time.

     The operation of ntpdc are specific to the particular implementation of the
     ntpd(8) daemon and can be expected to work only with this	and  maybe  some
     previous  versions  of  the  daemon.   Requests from a remote ntpdc utility
     which affect the state of the local server must be authenticated, which re-
     quires both the remote program and local server share a common key and  key
     identifier.

     Note that in contexts where a host name is expected, a -4 qualifier preced-
     ing  the  host name forces DNS resolution to the IPv4 namespace, while a -6
     qualifier forces DNS resolution to the IPv6 namespace.  Specifying  a  com-
     mand  line  option  other	than  -i  or  -n  will cause the specified query
     (queries) to be sent to  the  indicated  host(s)  immediately.   Otherwise,
     ntpdc  will  attempt  to read interactive format commands from the standard
     input.

   Interactive Commands
     Interactive format commands consist of a keyword followed by zero	to  four
     arguments.  Only enough characters of the full keyword to uniquely identify
     the command need be typed.  The output of a command is normally sent to the
     standard  output,	but  optionally the output of individual commands may be
     sent to a file by appending a `>', followed by a file name, to the  command
     line.

     A	number	of  interactive format commands are executed entirely within the
     ntpdc utility itself and do not result in NTP mode 7 requests being sent to
     a server.	These are described following.

     ? command_keyword

     help command_keyword
	     A `?' will print a list of all the command keywords known	to  this
	     incarnation  of  ntpdc.   A  `?' followed by a command keyword will
	     print function and usage information about the command.  This  com-
	     mand  is probably a better source of information about ntpq(8) than
	     this manual page.

     delay milliseconds
	     Specify a time interval to be added to timestamps included  in  re-
	     quests which require authentication.  This is used to enable (unre-
	     liable) server reconfiguration over long delay network paths or be-
	     tween  machines  whose  clocks  are  unsynchronized.   Actually the
	     server does not now require timestamps in	authenticated  requests,
	     so this command may be obsolete.

     host hostname
	     Set the host to which future queries will be sent.  Hostname may be
	     either a host name or a numeric address.

     hostnames [yes | no]
	     If  yes  is  specified,  host names are printed in information dis-
	     plays.  If no is specified, numeric addresses are printed	instead.
	     The  default  is  yes,  unless  modified  using the command line -n
	     switch.

     keyid keyid
	     This command allows the specification of a key number to be used to
	     authenticate configuration requests.  This must correspond to a key
	     number the server has been configured to use for this purpose.

     quit    Exit ntpdc.

     passwd  This command prompts you to type in a password (which will  not  be
	     echoed)  which will be used to authenticate configuration requests.
	     The password must correspond to the key configured for use  by  the
	     NTP server for this purpose if such requests are to be successful.

     timeout milliseconds
	     Specify  a timeout period for responses to server queries.  The de-
	     fault is about 8000 milliseconds.	Note that  since  ntpdc  retries
	     each query once after a timeout, the total waiting time for a time-
	     out will be twice the timeout value set.

   Control Message Commands
     Query  commands result in NTP mode 7 packets containing requests for infor-
     mation being sent to the server.  These are read-only commands in that they
     make no modification of the server configuration state.

     listpeers
	     Obtains and prints a brief list of the peers for which  the  server
	     is maintaining state.  These should include all configured peer as-
	     sociations  as  well as those peers whose stratum is such that they
	     are considered by the server to be possible future  synchronization
	     candidates.

     peers   Obtains  a list of peers for which the server is maintaining state,
	     along with a summary of that state.  Summary  information	includes
	     the  address  of  the  remote  peer,  the	local  interface address
	     (0.0.0.0 if a local address has yet to be determined), the  stratum
	     of  the  remote  peer (a stratum of 16 indicates the remote peer is
	     unsynchronized), the polling interval, in seconds, the reachability
	     register, in octal, and the current  estimated  delay,  offset  and
	     dispersion of the peer, all in seconds.

	     The character in the left margin indicates the mode this peer entry
	     is  operating  in.  A `+' denotes symmetric active, a `-' indicates
	     symmetric passive, a `=' means the remote server is being polled in
	     client mode, a `^' indicates that the  server  is	broadcasting  to
	     this  address, a `~' denotes that the remote peer is sending broad-
	     casts and a `~' denotes that the remote peer is sending  broadcasts
	     and a `*' marks the peer the server is currently synchronizing to.

	     The contents of the host field may be one of four forms.  It may be
	     a	host  name, an IP address, a reference clock implementation name
	     with its parameter or REFCLK(implementation_number, parameter).  On
	     hostnames no only IP-addresses will be displayed.

     dmpeers
	     A slightly different peer summary list.  Identical to the output of
	     the peers command, except for the character in the leftmost column.
	     Characters only appear beside peers which were included in the  fi-
	     nal  stage  of the clock selection algorithm.  A `.' indicates that
	     this peer was cast off in the falseticker detection,  while  a  `+'
	     indicates	that  the  peer made it through.  A `*' denotes the peer
	     the server is currently synchronizing with.

     showpeer peer_address [...]
	     Shows a detailed display of the current peer variables for  one  or
	     more  peers.  Most of these values are described in the NTP Version
	     2 specification.

     pstats peer_address [...]
	     Show per-peer statistic  counters	associated  with  the  specified
	     peer(s).

     clockstat clock_peer_address [...]
	     Obtain  and  print information concerning a peer clock.  The values
	     obtained provide information on the setting of  fudge  factors  and
	     other clock performance information.

     kerninfo
	     Obtain and print kernel phase-lock loop operating parameters.  This
	     information is available only if the kernel has been specially mod-
	     ified for a precision timekeeping function.

     loopinfo [oneline | multiline]
	     Print  the values of selected loop filter variables.  The loop fil-
	     ter is the part of NTP which deals with adjusting the local  system
	     clock.  The `offset' is the last offset given to the loop filter by
	     the packet processing code.  The `frequency' is the frequency error
	     of  the  local  clock in parts-per-million (ppm).	The `time_const'
	     controls the stiffness of the phase-lock loop and thus the speed at
	     which it can adapt to oscillator drift.  The `watchdog timer' value
	     is the number of seconds which have elapsed since the  last  sample
	     offset was given to the loop filter.  The oneline and multiline op-
	     tions  specify  the  format  in  which  this  information	is to be
	     printed, with multiline as the default.

     sysinfo
	     Print a variety of system state variables, i.e., state  related  to
	     the  local server.  All except the last four lines are described in
	     the NTP Version 3 specification, RFC-1305.

	     The `system flags' show various system flags, some of which can  be
	     set  and  cleared by the enable and disable configuration commands,
	     respectively.  These are the auth, bclient, monitor, pll,	pps  and
	     stats  flags.   See  the  ntpd(8)	documentation for the meaning of
	     these flags.  There are two additional flags which are  read  only,
	     the  kernel_pll  and kernel_pps.  These flags indicate the synchro-
	     nization status when the precision time kernel modifications are in
	     use.  The `kernel_pll' indicates that the local clock is being dis-
	     ciplined by the kernel, while the `kernel_pps' indicates the kernel
	     discipline is provided by the PPS signal.

	     The `stability' is the residual frequency error remaining after the
	     system frequency correction is applied and is intended for  mainte-
	     nance  and  debugging.  In most architectures, this value will ini-
	     tially decrease from as high as 500 ppm to a nominal value  in  the
	     range  .01  to  0.1  ppm.	 If  it remains high for some time after
	     starting the daemon, something may be wrong with the  local  clock,
	     or  the value of the kernel variable kern.clockrate.tick may be in-
	     correct.

	     The `broadcastdelay' shows the default broadcast delay, as  set  by
	     the broadcastdelay configuration command.

	     The  `authdelay'  shows the default authentication delay, as set by
	     the authdelay configuration command.

     sysstats
	     Print statistics counters maintained in the protocol module.

     memstats
	     Print statistics counters related to memory allocation code.

     iostats
	     Print statistics counters maintained in the input-output module.

     timerstats
	     Print statistics counters maintained in the timer/event queue  sup-
	     port code.

     reslist
	     Obtain and print the server's restriction list.  This list is (usu-
	     ally)  printed  in  sorted order and may help to understand how the
	     restrictions are applied.

     monlist [version]
	     Obtain and print traffic counts collected	and  maintained  by  the
	     monitor  facility.   The version number should not normally need to
	     be specified.

     clkbug clock_peer_address [...]
	     Obtain debugging information for a reference  clock  driver.   This
	     information  is  provided	only by some clock drivers and is mostly
	     undecodable without a copy of the driver source in hand.

   Runtime Configuration Requests
     All requests which cause state changes in the server are  authenticated  by
     the server using a configured NTP key (the facility can also be disabled by
     the server by not configuring a key).  The key number and the corresponding
     key must also be made known to ntpdc.  This can be done using the keyid and
     passwd  commands,	the  latter  of  which will prompt at the terminal for a
     password to use as the encryption key.  You will also be prompted automati-
     cally for both the key number and password the first time a  command  which
     would result in an authenticated request to the server is given.  Authenti-
     cation  not only provides verification that the requester has permission to
     make such changes, but also gives	an  extra  degree  of  protection  again
     transmission errors.

     Authenticated requests always include a timestamp in the packet data, which
     is  included in the computation of the authentication code.  This timestamp
     is compared by the server to its receive time stamp.   If	they  differ  by
     more  than  a  small  amount the request is rejected.  This is done for two
     reasons.  First, it makes simple replay attacks on the server,  by  someone
     who  might  be  able  to overhear traffic on your LAN, much more difficult.
     Second, it makes it more difficult to request configuration changes to your
     server from topologically remote hosts.  While the reconfiguration facility
     will work well with a server on the local host, and may work adequately be-
     tween time-synchronized hosts on the same LAN, it will work very poorly for
     more distant hosts.  As such, if reasonable passwords are chosen,	care  is
     taken in the distribution and protection of keys and appropriate source ad-
     dress  restrictions  are  applied,  the  run  time reconfiguration facility
     should provide an adequate level of security.

     The following commands all make authenticated requests.

     addpeer peer_address [keyid] [version] [prefer]
	     Add a configured peer association at the given address and  operat-
	     ing  in  symmetric  active mode.  Note that an existing association
	     with the same peer may be deleted when this command is executed, or
	     may simply be converted to conform to the new configuration, as ap-
	     propriate.  If the optional keyid is a nonzero integer, all  outgo-
	     ing  packets to the remote server will have an authentication field
	     attached encrypted with this key.	If the value is 0 (or not given)
	     no authentication will be done.  The version can be 1, 2 or  3  and
	     defaults  to 3.  The prefer keyword indicates a preferred peer (and
	     thus will be used primarily for clock synchronisation if possible).
	     The preferred peer also determines the validity of the PPS signal -
	     if the preferred peer is suitable for synchronisation so is the PPS
	     signal.

     addserver peer_address [keyid] [version] [prefer]
	     Identical to the addpeer command, except that the operating mode is
	     client.

     broadcast peer_address [keyid] [version] [prefer]
	     Identical to the addpeer command, except that the operating mode is
	     broadcast.  In this case a valid key identifier  and  key	are  re-
	     quired.  The peer_address parameter can be the broadcast address of
	     the local network or a multicast group address assigned to NTP.  If
	     a multicast address, a multicast-capable kernel is required.

     unconfig peer_address [...]
	     This command causes the configured bit to be removed from the spec-
	     ified  peer(s).  In many cases this will cause the peer association
	     to be deleted.  When appropriate, however, the association may per-
	     sist in an unconfigured mode if the remote peer is willing to  con-
	     tinue on in this fashion.

     fudge peer_address [time1] [time2] [stratum] [refid]
	     This  command  provides  a  way to set certain data for a reference
	     clock.  See the source listing for further information.

     enable [auth | bclient | calibrate | kernel | monitor | ntp | pps | stats]

     disable [auth | bclient | calibrate | kernel | monitor | ntp | pps | stats]
	     These commands operate in the same way as the  enable  and  disable
	     configuration file commands of ntpd(8).

	     auth    Enables  the  server to synchronize with unconfigured peers
		     only if the peer has been correctly authenticated using ei-
		     ther public key or private key cryptography.   The  default
		     for this flag is enable.

	     bclient
		     Enables the server to listen for a message from a broadcast
		     or multicast server, as in the multicastclient command with
		     default address.  The default for this flag is disable.

	     calibrate
		     Enables  the  calibrate  feature for reference clocks.  The
		     default for this flag is disable.

	     kernel  Enables the kernel time discipline, if available.	The  de-
		     fault for this flag is enable if support is available, oth-
		     erwise disable.

	     monitor
		     Enables  the  monitoring  facility.   See the documentation
		     here about the monlist command or further information.  The
		     default for this flag is enable.

	     ntp     Enables time and frequency  discipline.   In  effect,  this
		     switch  opens and closes the feedback loop, which is useful
		     for testing.  The default for this flag is enable.

	     pps     Enables the pulse-per-second (PPS)  signal  when  frequency
		     and  time is disciplined by the precision time kernel modi-
		     fications.   See  the  "A	Kernel	 Model	 for   Precision
		     Timekeeping"  (available  as part of the HTML documentation
		     provided in /usr/share/doc/ntp) page for  further	informa-
		     tion.  The default for this flag is disable.

	     stats   Enables  the  statistics  facility.   See	the  "Monitoring
		     Options" section of ntp.conf(5)  for  further  information.
		     The default for this flag is disable.

     restrict address mask flag [...]
	     This command operates in the same way as the restrict configuration
	     file commands of ntpd(8).

     unrestrict address mask flag [...]
	     Unrestrict the matching entry from the restrict list.

     delrestrict address mask [ntpport]
	     Delete the matching entry from the restrict list.

     readkeys
	     Causes  the  current  set of authentication keys to be purged and a
	     new set to be obtained by rereading the keys file (which must  have
	     been specified in the ntpd(8) configuration file).  This allows en-
	     cryption keys to be changed without restarting the server.

     trustedkey keyid [...]

     untrustedkey keyid [...]
	     These  commands  operate  in  the	same  way  as the trustedkey and
	     untrustedkey configuration file commands of ntpd(8).

     authinfo
	     Returns information concerning the authentication module, including
	     known keys and counts of encryptions  and	decryptions  which  have
	     been done.

     traps   Display  the  traps  set in the server.  See the source listing for
	     further information.

     addtrap address [port] [interface]
	     Set a trap for asynchronous messages.  See the source  listing  for
	     further information.

     clrtrap address [port] [interface]
	     Clear a trap for asynchronous messages.  See the source listing for
	     further information.

     reset   Clear  the  statistics  counters  in various modules of the server.
	     See the source listing for further information.

ENVIRONMENT
     See OPTION PRESETS for configuration environment variables.

FILES
     See OPTION PRESETS for configuration files.

EXIT STATUS
     One of the following exit values will be returned:

     0	(EXIT_SUCCESS)
	     Successful program execution.

     1	(EXIT_FAILURE)
	     The operation failed or the command syntax was not valid.

     66  (EX_NOINPUT)
	     A specified configuration file could not be loaded.

     70  (EX_SOFTWARE)
	     libopts had an internal operational error.  Please report it to au-
	     togen-users@lists.sourceforge.net.  Thank you.

SEE ALSO
     ntp.conf(5), ntpd(8)

     David L. Mills, Network Time Protocol (Version 3), RFC1305.

AUTHORS
     The formatting directives in this document came from FreeBSD.

COPYRIGHT
     Copyright (C) 1992-2024 The University of Delaware and Network Time Founda-
     tion all rights reserved.	This program is released under the terms of  the
     NTP license, <http://ntp.org/license>.

BUGS
     The  ntpdc  utility  is  a crude hack.  Much of the information it shows is
     deadly boring and could only be loved by its implementer.	The program  was
     designed  so  that  new  (and  temporary) features were easy to hack in, at
     great expense to the program's ease of use.  Despite this, the  program  is
     occasionally useful.

     Please report bugs to http://bugs.ntp.org .

     Please send bug reports to: https://bugs.ntp.org, bugs@ntp.org

NOTES
     This manual page was AutoGen-erated from the ntpdc option definitions.

FreeBSD ports 15.quarterly	   May 25 2024				NTPDC(8)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=ntpdc&sektion=8&manpath=FreeBSD+Ports+15.1.quarterly>

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