NTPDC(1)						      General Commands Manual							  NTPDC(1)

NAME

       ntpdc - special NTP query program

SYNOPSIS

       ntpdc [-ilnps] [-c command] [host] [...]

DESCRIPTION

       ntpdc  is  used	to  query  the	ntpd daemon about its current state and to request changes in that state. The program may be run either in
       interactive 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.

       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 commands 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. ntpdc will prompt for commands if the standard input is a terminal
       device.

       ntpdc 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. ntpdc makes no attempt to retransmit requests, 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 daemon and can be expected to work only with this and
       maybe some previous versions of the daemon. Requests from a remote ntpdc program which affect the state of the local server must be authen-
       ticated, which requires 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 preceding the host name forces DNS resolution to the IPv4 namespace,
       while a -6 qualifier forces DNS resolution to the IPv6 namespace.

OPTIONS

       Specifying a command line option other than -i or -n will cause the specified query (queries) to be sent to the indicated  host(s)  immedi-
       ately. Otherwise, ntpdc will attempt to read interactive format commands from the standard input.

       -4     Force DNS resolution of following host names on the command line to the IPv4 namespace.

       -6     Force DNS resolution of following host names on the command line to the IPv6 namespace.

       -c command
	      The  following  argument	is interpreted as an interactive format command and is added to the list of commands to be executed on the
	      specified host(s). Multiple -c options may be given.

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

       -l     Obtain a list of peers which are known to the server(s). This switch is equivalent to -c listpeers.

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

       -p     Print a list of the peers known to the server as well as a summary of their state. This is equivalent to -c peers.

       -s     Print  a	list  of the peers known to the server as well as a summary of their state, but in a slightly different format than the -p
	      switch. This is equivalent to -c dmpeers.

SEE ALSO

       /usr/share/doc/ntp-doc/html/ntpdc.html for the full documentation.

Network Time Protocol						  October 7, 2006							  NTPDC(1)