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NTPQ(8)			FreeBSD	System Manager's Manual		       NTPQ(8)

NAME
     ntpq -- standard NTP query	program

SYNOPSIS
     ntpq [-inp] [-c command] [host ...]

DESCRIPTION
     The ntpq utility is used to query NTP servers which implement the recom-
     mended NTP	mode 6 control message format about current state and to
     request changes in	that state.  The program may be	run either in interac-
     tive mode or controlled using command line	arguments.  Requests to	read
     and write arbitrary variables can be assembled, with raw and pretty-
     printed output options being available.  The ntpq utility can also	obtain
     and print a list of peers in a common format by sending multiple queries
     to	the server.

     If	one or more request options is included	on the command line when ntpq
     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,	ntpq 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 local-
     host when no other	host is	specified.  The	ntpq utility will prompt for
     commands if the standard input is a terminal device.

     The ntpq utility uses NTP mode 6 packets to communicate with the NTP
     server, and hence can be used to query any	compatible server on the net-
     work which	permits	it.  Note that since NTP is a UDP protocol this	commu-
     nication will be somewhat unreliable, especially over large distances in
     terms of network topology.	 The ntpq utility makes	one attempt to
     retransmit	requests, and will time	requests out if	the remote host	is not
     heard from	within a suitable timeout time.

     For examples and usage, see the "NTP Debugging Techniques"	page (avail-
     able as part of the HTML documentation provided in	/usr/share/doc/ntp).

     The following options are available:

     -c	     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 ntpq	to operate in interactive mode.	 Prompts will be writ-
	     ten to the	standard output	and commands read from the standard
	     input.

     -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	sum-
	     mary of their state.  This	is equivalent to the peers interactive
	     command.

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

   Internal Commands
     Interactive format	commands consist of a keyword followed by zero to four
     arguments.	 Only enough characters	of the full keyword to uniquely	iden-
     tify 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 ntpq utility itself and do not	result in NTP mode 6
     requests being sent to a server.  These are described following.

     ? [command_keyword]

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

     addvars variable_name[=value ...]

     rmvars variable_name ...

     clearvars
	     The data carried by NTP mode 6 messages consists of a list	of
	     items of the form `variable_name=value', where the	`=value' is
	     ignored, and can be omitted, in requests to the server to read
	     variables.	 The ntpq utility maintains an internal	list in	which
	     data to be	included in control messages can be assembled, and
	     sent using	the readlist and writelist commands described below.
	     The addvars command allows	variables and their optional values to
	     be	added to the list.  If more than one variable is to be added,
	     the list should be	comma-separated	and not	contain	white space.
	     The rmvars	command	can be used to remove individual variables
	     from the list, while the clearlist	command	removes	all variables
	     from the list.

     authenticate yes |	no
	     Normally ntpq does	not authenticate requests unless they are
	     write requests.  The command `authenticate	yes' causes ntpq to
	     send authentication with all requests it makes.  Authenticated
	     requests causes some servers to handle requests slightly differ-
	     ently, and	can occasionally melt the CPU in fuzzballs if you turn
	     authentication on before doing a peer display.

     cooked  Causes output from	query commands to be "cooked", so that vari-
	     ables which are recognized	by ntpq	will have their	values refor-
	     matted for	human consumption.  Variables which ntpq thinks	should
	     have a decodable value but	didn't are marked with a trailing `?'.

     debug more	| less | off
	     Turns internal query program debugging on and off.

     delay milliseconds
	     Specify a time interval to	be added to timestamps included	in
	     requests which require authentication.  This is used to enable
	     (unreliable) server reconfiguration over long delay network paths
	     or	between	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 pur-
	     pose.

     ntpversion	1 | 2 |	3 | 4
	     Sets the NTP version number which ntpq claims in packets.
	     Defaults to 3, Note that mode 6 control messages (and modes, for
	     that matter) didn't exist in NTP version 1.  There	appear to be
	     no	servers	left which demand version 1.

     quit    Exit ntpq.

     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.

     raw     Causes all	output from query commands is printed as received from
	     the remote	server.	 The only formating/interpretation done	on the
	     data is to	transform nonascii data	into a printable (but barely
	     understandable) form.

     timeout milliseconds
	     Specify a timeout period for responses to server queries.	The
	     default is	about 5000 milliseconds.  Note that since ntpq retries
	     each query	once after a timeout, the total	waiting	time for a
	     timeout will be twice the timeout value set.

   Control Message Commands
     Each peer known to	an NTP server has a 16 bit integer association identi-
     fier assigned to it.  NTP control messages	which carry peer variables
     must identify the peer the	values correspond to by	including its associa-
     tion ID.  An association ID of 0 is special, and indicates	the variables
     are system	variables, whose names are drawn from a	separate name space.

     Control message commands result in	one or more NTP	mode 6 messages	being
     sent to the server, and cause the data returned to	be printed in some
     format.  Most commands currently implemented send a single	message	and
     expect a single response.	The current exceptions are the peers command,
     which will	send a preprogrammed series of messages	to obtain the data it
     needs, and	the mreadlist and mreadvar commands, which will	iterate	over a
     range of associations.

     associations
	     Obtains and prints	a list of association identifiers and peer
	     statuses for in-spec peers	of the server being queried.  The list
	     is	printed	in columns.  The first of these	is an index numbering
	     the associations from 1 for internal use, the second the actual
	     association identifier returned by	the server and the third the
	     status word for the peer.	This is	followed by a number of	col-
	     umns containing data decoded from the status word.	 See the peers
	     command for a decode of the `condition' field.  Note that the
	     data returned by the associations command is cached internally in
	     ntpq.  The	index is then of use when dealing with stupid servers
	     which use association identifiers which are hard for humans to
	     type, in that for any subsequent commands which require an	asso-
	     ciation identifier	as an argument,	the form of index may be used
	     as	an alternative.

     clockvar [assocID]	[variable_name[=value ...]] ...

     cv	[assocID] [variable_name[=value	...]] ...
	     Requests that a list of the server's clock	variables be sent.
	     Servers which have	a radio	clock or other external	synchroniza-
	     tion will respond positively to this.  If the association identi-
	     fier is omitted or	zero the request is for	the variables of the
	     `system clock' and	will generally get a positive response from
	     all servers with a	clock.	If the server treats clocks as pseudo-
	     peers, and	hence can possibly have	more than one clock connected
	     at	once, referencing the appropriate peer association ID will
	     show the variables	of a particular	clock.	Omitting the variable
	     list will cause the server	to return a default variable display.

     lassociations
	     Obtains and prints	a list of association identifiers and peer
	     statuses for all associations for which the server	is maintaining
	     state.  This command differs from the associations	command	only
	     for servers which retain state for	out-of-spec client associa-
	     tions (i.e., fuzzballs).  Such associations are normally omitted
	     from the display when the associations command is used, but are
	     included in the output of lassociations.

     lpassociations
	     Print data	for all	associations, including	out-of-spec client
	     associations, from	the internally cached list of associations.
	     This command differs from passociations only when dealing with
	     fuzzballs.

     lpeers  Like R peers, except a summary of all associations	for which the
	     server is maintaining state is printed.  This can produce a much
	     longer list of peers from fuzzball	servers.

     mreadlist assocID assocID

     mrl assocID assocID
	     Like the readlist command,	except the query is done for each of a
	     range of (nonzero)	association IDs.  This range is	determined
	     from the association list cached by the most recent associations
	     command.

     mreadvar assocID assocID [variable_name[=value ...]]

     mrv assocID assocID [variable_name[=value ...]]
	     Like the readvar command, except the query	is done	for each of a
	     range of (nonzero)	association IDs.  This range is	determined
	     from the association list cached by the most recent associations
	     command.

     opeers  An	old form of the	peers command with the reference ID replaced
	     by	the local interface address.

     passociations
	     Displays association data concerning in-spec peers	from the
	     internally	cached list of associations.  This command performs
	     identically to the	associations except that it displays the
	     internally	stored data rather than	making a new query.

     peers   Obtains a current list peers of the server, along with a summary
	     of	each peer's state.  Summary information	includes the address
	     of	the remote peer, the reference ID (0.0.0.0 if this is
	     unknown), the stratum of the remote peer, the type	of the peer
	     (local, unicast, multicast	or broadcast), when the	last packet
	     was received, the polling interval, in seconds, the reachability
	     register, in octal, and the current estimated delay, offset and
	     dispersion	of the peer, all in milliseconds.  The character in
	     the left margin indicates the fate	of this	peer in	the clock
	     selection process.	 Following is a	list of	these characters, the
	     pigeon used in the	rv command, and	a short	explanation of the
	     condition revealed.

	     space   (reject) The peer is discarded as unreachable, synchro-
		     nized to this server (synch loop) or outrageous synchro-
		     nization distance.

	     x	     (falsetick) The peer is discarded by the intersection
		     algorithm as a falseticker.

	     .	     (excess) The peer is discarded as not among the first ten
		     peers sorted by synchronization distance and so is	proba-
		     bly a poor	candidate for further consideration.

	     -	     (outlyer) The peer	is discarded by	the clustering algo-
		     rithm as an outlyer.

	     +	     (candidate) The peer is a survivor	and a candidate	for
		     the combining algorithm.

	     #	     (selected)	The peer is a survivor,	but not	among the
		     first six peers sorted by synchronization distance.  If
		     the association is	ephemeral, it may be demobilized to
		     conserve resources.

	     *	     (peer) The	peer has been declared the system peer and
		     lends its variables to the	system variables.

	     o	     ((pps.peer)) The peer has been declared the system	peer
		     and lends its variables to	the system variables.  How-
		     ever, the actual system synchronization is	derived	from a
		     pulse-per-second (PPS) signal, either indirectly via the
		     PPS reference clock driver	or directly via	kernel inter-
		     face.

     The flash variable	is a valuable debugging	aid.  It displays the results
     of	the original sanity checks defined in the NTP specification RFC-1305
     and additional ones added in NTP Version 4.  There	are eleven tests
     called TEST1 through TEST11.  The tests are performed in a	certain	order
     designed to gain maximum diagnostic information while protecting against
     accidental	or malicious errors.  The flash	variable is first initialized
     to	zero.  If after	each set of tests one or more bits are set, the	packet
     is	discarded.

     Tests TEST4 and TEST5 check the access permissions	and cryptographic mes-
     sage digest.  If any bits are set after that, the packet is discarded.
     Tests TEST10 and TEST11 check the authentication state using Autokey pub-
     lic-key cryptography, as described	in the Authentication Options section
     of	ntp.conf(5).  If any bits are set and the association has previously
     been marked reachable, the	packet is discarded; otherwise,	the originate
     and receive timestamps are	saved, as required by the NTP protocol,	and
     processing	continues.

     Tests TEST1 through TEST3 check the packet	timestamps from	which the off-
     set and delay are calculated.  If any bits	are set, the packet is dis-
     carded; otherwise,	the packet header variables are	saved.	Tests TEST6
     through TEST8 check the health of the server.  If any bits	are set, the
     packet is discarded; otherwise, the offset	and delay relative to the
     server are	calculated and saved.  Test TEST9 checks the health of the
     association itself.  If any bits are set, the packet is discarded;	other-
     wise, the saved variables are passed to the clock filter and mitigation
     algorithms.

     The flash bits for	each test read in increasing order from	the least sig-
     nificant bit are defined as follows.

     TEST1   Duplicate packet.	The packet is at best a	casual retransmission
	     and at worst a malicious replay.

     TEST2   Bogus packet.  The	packet is not a	reply to a message previously
	     sent.  This can happen when the NTP daemon	is restarted and
	     before somebody else notices.

     TEST3   Unsynchronized.  One or more timestamp fields are invalid.	 This
	     normally happens when the first packet from a peer	is received.

     TEST4   Access is denied.	See the	"Access	Control" page.

     TEST5   Cryptographic authentication fails.  See the Authentication
	     Options section of	ntp.conf(5).

     TEST6   The server	is unsynchronized.  Wind up its	clock first.

     TEST7   The server	stratum	is at the maximum than 15.  It is probably
	     unsynchronized and	its clock needs	to be wound up.

     TEST8   Either the	root delay or dispersion is greater than one second,
	     which is highly unlikely unless the peer is synchronized to Mars.

     TEST9   Either the	peer delay or dispersion is greater than one second,
	     which is highly unlikely unless the peer is on Mars.

     TEST10  The autokey protocol has detected an authentication failure.  See
	     the Authentication	Options	section	of ntp.conf(5).

     TEST11  The autokey protocol has not verified the server or peer is
	     authentic and has valid public key	credentials.  See the
	     Authentication Options section of ntp.conf(5).

     Additional	system variables used by the NTP Version 4 Autokey support
     include the following:

     certificate filestamp
	     Shows the NTP seconds when	the certificate	file was created.

     hostname host
	     Shows the name of the host	as returned by the Unix	gethostname(3)
	     library function.

     flags hex
	     Shows the current flag bits, where	the hex	bits are interpreted
	     as	follows:

	     0x01    autokey enabled

	     0x02    RSA public/private	key files present

	     0x04    PKI certificate file present

	     0x08    Diffie-Hellman parameters file present

	     0x10    NIST leapseconds table file present

     leapseconds filestamp
	     Shows the NTP seconds when	the NIST leapseconds table file	was
	     created.

     params filestamp
	     Shows the NTP seconds when	the Diffie-Hellman agreement parameter
	     file was created.

     publickey filestamp
	     Shows the NTP seconds when	the RSA	public/private key files were
	     created.

     refresh filestamp
	     Shows the NTP seconds when	the public cryptographic values	were
	     refreshed and signed.

     tai offset
	     Shows the TAI-UTC offset in seconds obtained from the NIST
	     leapseconds table.

     Additional	peer variables used by the NTP Version 4 Autokey support
     include the following:

     certificate filestamp
	     Shows the NTP seconds when	the certificate	file was created.

     flags hex
	     Shows the current flag bits, where	the hex	bits are interpreted
	     as	in the system variable of the same name.  The bits are set in
	     the first autokey message received	from the server	and then reset
	     as	the associated data are	obtained from the server and stored.

     hcookie hex
	     Shows the host cookie used	in the key agreement algorithm.

     initkey key
	     Shows the initial key used	by the key list	generator in the
	     autokey protocol.

     initsequence index
	     Shows the initial index used by the key list generator in the
	     autokey protocol.

     pcookie hex
	     Specifies the peer	cookie used in the key agreement algorithm.

     timestamp time
	     Shows the NTP seconds when	the last autokey key list was gener-
	     ated and signed.

     pstatus assocID
	     Sends a read status request to the	server for the given associa-
	     tion.  The	names and values of the	peer variables returned	will
	     be	printed.  Note that the	status word from the header is dis-
	     played preceding the variables, both in hexadecimal and in	pid-
	     geon English.

     readlist assocID

     rl	assocID
	     Requests that the values of the variables in the internal vari-
	     able list be returned by the server.  If the association ID is
	     omitted or	is 0 the variables are assumed to be system variables.
	     Otherwise they are	treated	as peer	variables.  If the internal
	     variable list is empty a request is sent without data, which
	     should induce the remote server to	return a default display.

     readvar assocID variable_name[=value] ...

     rv	assocID	variable_name[=value] ...
	     Requests that the values of the specified variables be returned
	     by	the server by sending a	read variables request.	 If the	asso-
	     ciation ID	is omitted or is given as zero the variables are sys-
	     tem variables, otherwise they are peer variables and the values
	     returned will be those of the corresponding peer.	Omitting the
	     variable list will	send a request with no data which should
	     induce the	server to return a default display.

     writevar assocID variable_name[=value] ...
	     Like the readvar request, except the specified variables are
	     written instead of	read.

     writelist [assocID]
	     Like the readlist request,	except the internal list variables are
	     written instead of	read.

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

BUGS
     The peers command is non-atomic and may occasionally result in spurious
     error messages about invalid associations occurring and terminating the
     command.  The timeout time	is a fixed constant, which means you wait a
     long time for timeouts since it assumes sort of a worst case.  The	pro-
     gram should improve the timeout estimate as it sends queries to a partic-
     ular host,	but doesn't.

FreeBSD	10.1			January	7, 2000			  FreeBSD 10.1

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | BUGS

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