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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 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
     available.  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
     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.  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
     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 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
     (available 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
             written 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
             summary of their state.  This is equivalent to the peers
             interactive command.

     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.
     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
     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 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
             command.  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
             variables which are recognized by ntpq will have their values
             reformatted 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
             displays.  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 formatting/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
     identify 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
             columns 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 association 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
             synchronization will respond positively to this.  If the
             association identifier 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
             associations (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
             association.  The names and values of the peer variables returned
             will be printed.  Note that the status word from the header is
             displayed preceding the variables, both in hexadecimal and in
             pidgeon English.

     readlist assocID

     rl assocID
             Requests that the values of the variables in the internal
             variable 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
             association ID is omitted or is given as zero the variables are
             system 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
             candidate 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
             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.

     *       (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
             system synchronization is derived from a pulse-per-second (PPS)
             signal, 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
             exponential 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
             identifier (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
     specification, as are the timestamps org, rec and xmt.  Additional NTPv4
     system 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
             exponential average of RMS time differences.

     unreach
             The value of the counter which records the number of poll
             intervals 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
     variables 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 performed in a certain order designed to gain maximum diagnostic
     information while protecting against accidental or malicious errors.  The
     flash variable 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
     offset and delay are calculated.  If any bits are set, the packet is
     discarded; otherwise, the packet header variables are saved.  TEST4 and
     TEST5 are associated with access control and cryptographic
     authentication.  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
     relative 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
     mitigation algorithms.

     Tests TEST10 through TEST12 check the authentication state using Autokey
     public-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.

     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
             unsynchronized 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
     program should improve the timeout estimate as it sends queries to a
     particular host, but does not.

FreeBSD 11.0-PRERELEASE          May 17, 2006          FreeBSD 11.0-PRERELEASE

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | BUGS

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