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NTPQ(8)			  BSD 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 monitor NTP daemon ntpd(8) operations and
     determine performance.  It uses the standard NTP mode 6 control message
     formats defined in Appendix B of the NTPv3 specification RFC1305.	The
     same formats are used in NTPv4, although some of the variables have
     changed and new ones added.  The description on this page is for the
     NTPv4 variables.

     The program can be run either in interactive 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 avail‐
     able.  The ntpq can also obtain and print a list of peers in a common
     format by sendingmultiple 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:

     -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	     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.

     -d	     Turn on debugging mode.

     -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.

     Note that in contexts where a host name is expected, a -4 qualifier pre‐
     ceding the host name forces DNS resolution to the IPv4 namespace, while a
     -6 qualifier forces DNS resolution to the IPv6 namespace.	Specifying a
     command line option other than -i or -n will cause the specified 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.

     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 did not 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 specifies the 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.

     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) did not exist in NTP version 1.  There appear to be
	     no servers left which demand version 1.

     passwd  This command prompts for a password (which will not be echoed)
	     which will be used to authenticate configuration requests.	 The
	     password must correspond to the key configured for NTP server for
	     this purpose.

     quit    Exit ntpq.

     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 association known to an NTP server has a 16 bit integer association
     identifier.  NTP control messages which carry peer variables must iden‐
     tify the peer the values correspond to by including its association 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 and 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 at
	     the left margin of each line shows the synchronization status of
	     the association and is a valuable diagnostic tool.	 The encoding
	     and meaning of this character, called the tally code, is given
	     later in this page.

     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.  The encoding and
	     meaning of the variables derived from NTPv3 is given in RFC-1305;
	     the encoding and meaning of the additional NTPv4 variables are
	     given later in this page.

     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.

   Tally Codes
     The character in the left margin in the ‘peers’ billboard, called the
     tally code, shows the fate of each association 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, synchronized to
	     this server (synch loop) or outrageous synchronization 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 probably a poor can‐
	     didate for further consideration.

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

     +	     (candidat) The peer is a survivor and a candidate for the combin‐
	     ing 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.

     *	     (sys.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.  However, the actual sys‐
	     tem synchronization is derived from a pulse-per-second (PPS) sig‐
	     nal, either indirectly via the PPS reference clock driver or
	     directly via kernel interface.

   System Variables
     The status, leap, stratum, precision, rootdelay, rootdispersion, refid,
     reftime, poll, offset, and frequency variables are described in RFC-1305
     specification.  Additional NTPv4 system variables include the following.

     version
	     Everything you might need to know about the software version and
	     generation time.

     processor
	     The processor and kernel identification string.

     system  The operating system version and release identifier.

     state   The state of the clock discipline state machine.  The values are
	     described in the architecture briefing on the NTP Project page
	     linked from www.ntp.org.

     peer    The internal integer used to identify the association currently
	     designated the system peer.

     jitter  The estimated time error of the system clock measured as an expo‐
	     nential average of RMS time differences.

     stability
	     The estimated frequency stability of the system clock measured as
	     an exponential average of RMS frequency differences.

     When the NTPv4 daemon is compiled with the OpenSSL software library,
     additional system variables are displayed, including some or all of the
     following, depending on the particular dance:

     flags   The current flags word bits and message digest algorithm identi‐
	     fier (NID) in hex format.	The high order 16 bits of the four-
	     byte word contain the NID from the OpenSSL ligrary, while the
	     low-order bits are interpreted as follows:

	     0x01    autokey enabled

	     0x02    NIST leapseconds file loaded

	     0x10    PC identity scheme

	     0x20    IFF identity scheme

	     0x40    GQ identity scheme

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

     hostkey
	     The NTP filestamp of the host key file.

     cert    A list of certificates held by the host.  Each entry includes the
	     subject, issuer, flags and NTP filestamp in order.	 The bits are
	     interpreted as follows:

	     0x01    certificate has been signed by the server

	     0x02    certificate is trusted

	     0x04    certificate is private

	     0x08    certificate contains errors and should not be trusted

     leapseconds
	     The NTP filestamp of the NIST leapseconds file.

     refresh
	     The NTP timestamp when the host public cryptographic values were
	     refreshed and signed.

     signature
	     The host digest/signature scheme name from the OpenSSL library.

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

   Peer Variables
     The status, srcadr, srcport, dstadr, dstport, leap, stratum, precision,
     rootdelay, rootdispersion, readh, hmode, pmode, hpoll, ppoll, offset,
     delay, dspersion, reftime variables are described in the RFC-1305 speci‐
     fication, as are the timestamps org, rec and xmt.	Additional NTPv4 sys‐
     tem variables include the following.

     flash   The flash code for the most recent packet received.  The encoding
	     and meaning of these codes is given later in this page.

     jitter  The estimated time error of the peer clock measured as an expo‐
	     nential average of RMS time differences.

     unreach
	     The value of the counter which records the number of poll inter‐
	     vals since the last valid packet was received.

     When the NTPv4 daemon is compiled with the OpenSSL software library,
     additional peer variables are displayed, including the following:

     flags   The current flag bits.  This word is the server host status word
	     with additional bits used by the Autokey state machine.  See the
	     source code for the bit encoding.

     hostname
	     The server host name.

     initkey key
	     The initial key used by the key list generator in the Autokey
	     protocol.

     initsequence index
	     The initial index used by the key list generator in the Autokey
	     protocol.

     signature
	     The server message digest/signature scheme name from the OpenSSL
	     software library.

     timestamp time
	     The NTP timestamp when the last Autokey key list was generated
	     and signed.

   Flash Codes
     The flash code is a valuable debugging aid displayed in the peer vari‐
     ables list.  It shows the results of the original sanity checks defined
     in the NTP specification RFC-1305 and additional ones added in NTPv4.
     There are 12 tests designated TEST1 through TEST12.  The tests are per‐
     formed in a certain order designed to gain maximum diagnostic information
     while protecting against accidental or malicious errors.  The flash vari‐
     able is initialized to zero as each packet is received.  If after each
     set of tests one or more bits are set, the packet is discarded.

     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.	TEST4 and
     TEST5 are associated with access control and cryptographic authentica‐
     tion.  If any bits are set, the packet is discarded immediately with
     nothing changed.

     Tests TEST6 through TEST8 check the health of the server.	If any bits
     are set, the packet is discarded; otherwise, the offset and delay rela‐
     tive to the server are calculated and saved.  TEST9 checks the health of
     the association itself.  If any bits are set, the packet is discarded;
     otherwise, the saved variables are passed to the clock filter and mitiga‐
     tion algorithms.

     Tests TEST10 through TEST12 check the authentication state using Autokey
     public-key cryptography, as described in the Authentication Options sec‐
     tion of ntp.conf(5).  If any bits are set and the association has previ‐
     ously been marked reachable, the packet is discarded; otherwise, the
     originate and receive timestamps are saved, as required by the NTP proto‐
     col, and processing continues.

     The flash bits for each test are defined as follows.

     0x001   (TEST1) Duplicate packet.	The packet is at best a casual
	     retransmission and at worst a malicious replay.

     0x002   (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.

     0x004   (TEST3) Unsynchronized.  One or more timestamp fields are
	     invalid.  This normally happens when the first packet from a peer
	     is received.

     0x008   (TEST4) Access is denied.	See the Access Control Support section
	     of ntp.conf(5).

     0x010   (TEST5) Cryptographic authentication fails.  See the
	     Authentication Options section of ntp.conf(5).

     0x020   (TEST6) The server is unsynchronized.  Wind up its clock first.

     0x040   (TEST7) The server stratum is at the maximum than 15.  It is
	     probably unsynchronized and its clock needs to be wound up.

     0x080   (TEST8) Either the root delay or dispersion is greater than one
	     second, which is highly unlikely unless the peer is unsynchro‐
	     nized to Mars.

     0x100   (TEST9) Either the peer delay or dispersion is greater than one
	     second, which is higly unlikely unless the peer is on Mars.

     0x200   (TEST10) The autokey protocol has detected an authentication
	     failure.  See the Authentication Options section of ntp.conf(5).

     0x400   (TEST11) The autokey protocol has not verified the server or peer
	     is proventic and has valid public key credentials.	 See the
	     Authentication Options section of ntp.conf(5).

     0x800   (TEST12) A protocol or configuration error has occurred in the
	     public key algorithms or a possible intrusion event has been
	     detected.	See the Authentication Options section of ntp.conf(5).

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 does not.

BSD				 May 17, 2006				   BSD
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