ntpq(1) User Commands ntpq(1)
ntpq - standard NTP query program
ntpq [-flags] [-flag [value]] [--option-name[[=| ]value]] [ host ...]
The ntpq utility program is used to query NTP servers to monitor NTP operations and performance, requesting information about current state
and/or changes in that state. The program may 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 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 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 termi-
ntpq 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.
Note that in contexts where a host name is expected, a -4 qualifier preceding the host name forces resolution to the IPv4 namespace, while
a -6 qualifier forces resolution to the IPv6 namespace. For examples and usage, see the NTP Debugging Techniques page.
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, ntpq will attempt to read interactive format commands from the standard input.
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.
A number of interactive format commands are executed entirely within the ntpq utility itself and do not result in NTP requests being sent
to a server. These are described following.
help [command] A '?' by itself will print a list of all the commands known to ntpq. A '?' followed by a command name will print function
and usage information about the command.
showvars The arguments to this command consist of a list of items of the form 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 messages can be assembled, and displayed or set 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 clearvars command removes all variables from the list. The showvars command displays the
current list of optional variables.
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 dif-
ferently. The command authenticate causes ntpq to display whether or not it is currently authenticating requests.
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 could not decode completely are marked with a trailing '?'.
With no argument, displays the current debug level. Otherwise, the debugging level is changed as indicated.
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. Without any
arguments, displays the current delay.
Display refids as IPv4 or hash. Without any arguments, displays whether refids are shown as IPv4 addresses or hashes.
exit Exit ntpq.
host [name] Set the host to which future queries will be sent. The name may be either a host name or a numeric address. Without any
arguments, displays the current host.
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. Without any arguments, displays whether
host names or numeric addresses are shown.
keyid [keyid] This command allows the specification of a key number to be used to authenticate configuration requests. This must corre-
spond to the controlkey key number the server has been configured to use for this purpose. Without any arguments, displays
the current keyid.
Specify the digest algorithm to use for authenticating requests, with default MD5. If ntpq was built with OpenSSL support,
and OpenSSL is installed, digest can be any message digest algorithm supported by OpenSSL. If no argument is given, the
current keytype digest algorithm used is displayed.
Sets the NTP version number which ntpq claims in packets. Defaults to 3, and 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. With no argu-
ment, displays the current NTP version that will be used when communicating with servers.
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.
poll [n] [verbose]
Poll an NTP server in client mode n times. Poll not implemented yet.
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.
Specify a timeout period for responses to server queries. The default is about 5000 milliseconds. Without any arguments,
displays the current timeout period. 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.
version Display the version of the ntpq program.
Control Message Commands
Association ids are used to identify system, peer and clock variables. System variables are assigned an association id of zero and system
name space, while each association is assigned a nonzero association id and peer namespace. Most control commands send a single message to
the server and expect a single response message. The exceptions are the peers command, which sends a series of messages, and the mreadlist
and mreadvar commands, which iterate over a range of associations.
apeers Display a list of peers in the form: where the output is just like the peers command except that the refid is displayed in hex
format and the association number is also displayed.
Display a list of mobilized associations in the form:
authinfo Display the authentication statistics counters: time since reset, stored keys, free keys, key lookups, keys not found, uncached
keys, expired keys, encryptions, decryptions.
Display all clock variables in the variable list for those associations supporting a reference clock.
clockvar [associd] [name[=value] ,...]
cv [associd] [name[=value] ,...]
Display a list of clock variables for those associations supporting a reference clock.
:config configuration command line
Send the remainder of the command line, including whitespace, to the server as a run-time configuration command in the same for-
mat as a line in the configuration file. This command is experimental until further notice and clarification. Authentication is
of course required.
Send each line of filename to the server as run-time configuration commands in the same format as lines in the configuration
file. This command is experimental until further notice and clarification. Authentication is required.
ifstats Display status and statistics counters for each local network interface address: interface number, interface name and address or
broadcast, drop, flag, ttl, mc, received, sent, send failed, peers, uptime. Authentication is required.
iostats Display network and reference clock I/O statistics: time since reset, receive buffers, free receive buffers, used receive buf-
fers, low water refills, dropped packets, ignored packets, received packets, packets sent, packet send failures, input wakeups,
useful input wakeups.
kerninfo Display kernel loop and PPS statistics: associd, status, pll offset, pll frequency, maximum error, estimated error, kernel sta-
tus, pll time constant, precision, frequency tolerance, pps frequency, pps stability, pps jitter, calibration interval, calibra-
tion cycles, jitter exceeded, stability exceeded, calibration errors. As with other ntpq output, times are in milliseconds; very
small values may be shown as exponentials. The precision value displayed is in milliseconds as well, unlike the precision system
Perform the same function as the associations command, except display mobilized and unmobilized associations, including all
Display a list of all peers and clients showing dstadr (associated with the given IP version).
Display the last obtained list of associations, including all clients.
Display a list of all peers and clients (associated with the given IP version).
monstats Display monitor facility status, statistics, and limits: enabled, addresses, peak addresses, maximum addresses, reclaim above
count, reclaim older than, kilobytes, maximum kilobytes.
mreadlist associdlo associdhi
mrl associdlo associdhi
Perform the same function as the readlist command for a range of association ids.
mreadvar associdlo associdhi [name][,...]
This range may be determined from the list displayed by any command showing associations.
mrv associdlo associdhi [name][,...]
Perform the same function as the readvar command for a range of association ids. This range may be determined from the list dis-
played by any command showing associations.
mrulist [limited | kod | mincount=count | laddr=localaddr | sort=[-]sortorder | resany=hexmask | resall=hexmask]
Display traffic counts of the most recently seen source addresses collected and maintained by the monitor facility. With the
exception of sort=[-]sortorder, the options filter the list returned by ntpd(8). The limited and kod options return only entries
representing client addresses from which the last packet received triggered either discarding or a KoD response. The min-
count=count option filters entries representing less than count packets. The laddr=localaddr option filters entries for packets
received on any local address other than localaddr. resany=hexmask and resall=hexmask filter entries containing none or less
than all, respectively, of the bits in hexmask, which must begin with 0x. The sortorder defaults to lstint and may be addr,
avgint, count, lstint, or any of those preceded by '-' to reverse the sort order. The output columns are:
lstint Interval in seconds between the receipt of the most recent packet from this address and the completion of the retrieval
of the MRU list by ntpq.
avgint Average interval in s between packets from this address.
rstr Restriction flags associated with this address. Most are copied unchanged from the matching restrict command, however
0x400 (kod) and 0x20 (limited) flags are cleared unless the last packet from this address triggered a rate control
r Rate control indicator, either a period, L or K for no rate control response, rate limiting by discarding, or rate lim-
iting with a KoD response, respectively.
m Packet mode.
v Packet version number.
count Packets received from this address.
rport Source port of last packet from this address.
host or DNS name, numeric address, or address followed by claimed DNS name which could not be verified in parentheses.
opeers [-4 | -6]
Obtain and print the old-style list of all peers and clients showing dstadr (associated with the given IP version), rather than
Perform the same function as the associations command, except that it uses previously stored data rather than making a new query.
peers Display a list of peers in the form:
[tally] single-character code indicating current value of the select field of the
remote host name (or IP number) of peer. The value displayed will be truncated to 15 characters unless the ntpq -w option is
given, in which case the full value will be displayed on the first line, and if too long, the remaining data will be
displayed on the next line.
refid source IP address or
st stratum: 0 for local reference clocks, 1 for servers with local reference clocks, ..., 16 for unsynchronized server
t u: unicast or manycast client, b: broadcast or multicast client, p: pool source, l: local (reference clock), s: symmet-
ric (peer), A: manycast server, B: broadcast server, M: multicast server
when time in seconds, minutes, hours, or days since the last packet was received, or '-' if a packet has never been received
poll poll interval (s)
reach reach shift register (octal)
delay roundtrip delay
offset offset of server relative to this host
jitter offset RMS error estimate.
Display the statistics for the peer with the given associd: associd, status, remote host, local address, time last received, time
until next send, reachability change, packets sent, packets received, bad authentication, bogus origin, duplicate, bad disper-
sion, bad reference time, candidate order.
Display all system or peer variables. If the associd is omitted, it is assumed to be zero.
readvar [associd name[=value] [, ...]]
rv [associd name[=value] [, ...]]
Display the specified system or peer variables. If associd is zero, the variables are from the System Variables name space, oth-
erwise they are from the Peer Variables name space. The associd is required, as the same name can occur in both spaces. If no
name is included, all operative variables in the name space are displayed. In this case only, if the associd is omitted, it is
assumed to be zero. Multiple names are specified with comma separators and without whitespace. Note that time values are repre-
sented in milliseconds and frequency values in parts-per-million (PPM). Some NTP timestamps are represented in the format YYYYMM
DD TTTT, where YYYY is the year, MM the month of year, DD the day of month and TTTT the time of day.
reslist Display the access control (restrict) list for ntpq. Authentication is required.
Save the current configuration, including any runtime modifications made by :config or config-from-file, to the NTP server host
file filename. This command will be rejected by the server unless appears in the ntpd(8) configuration file. filename can use
date(1) format specifiers to substitute the current date and time, for example,
The filename used is stored in system variable savedconfig. Authentication is required.
sysinfo Display system operational summary: associd, status, system peer, system peer mode, leap indicator, stratum, log2 precision, root
delay, root dispersion, reference id, reference time, system jitter, clock jitter, clock wander, broadcast delay, symm. auth.
sysstats Display system uptime and packet counts maintained in the protocol module: uptime, sysstats reset, packets received, current ver-
sion, older version, bad length or format, authentication failed, declined, restricted, rate limited, KoD responses, processed
Display interval timer counters: time since reset, timer overruns, calls to transmit.
Set all system or peer variables included in the variable list.
writevar associd name=value [, ...]
Set the specified variables in the variable list. If the associd is zero, the variables are from the System Variables name
space, otherwise they are from the Peer Variables name space. The associd is required, as the same name can occur in both spa-
ces. Authentication is required.
Status Words and Kiss Codes
The current state of the operating program is shown in a set of status words maintained by the system. Status information is also avail-
able on a per-association basis. These words are displayed by the readlist and associations commands both in hexadecimal and in decoded
short tip strings. The codes, tips and short explanations are documented on the page. The page also includes a list of system and peer
messages, the code for the latest of which is included in the status word.
Information resulting from protocol machine state transitions is displayed using an informal set of ASCII strings called The original pur-
pose was for kiss-o'-death (KoD) packets sent by the server to advise the client of an unusual condition. They are now displayed, when
appropriate, in the reference identifier field in various billboards.
The following system variables appear in the readlist billboard. Not all variables are displayed in some configurations.
version NTP software version and build time
processor hardware platform and version
system operating system and version
leap leap warning indicator (0-3)
stratum stratum (1-15)
precision precision (log2 s)
rootdelay total roundtrip delay to the primary reference clock
rootdisp total dispersion to the primary reference clock
refid reference id or
reftime reference time
clock date and time of day
peer system peer association id
tc time constant and poll exponent (log2 s) (3-17)
mintc minimum time constant (log2 s) (3-10)
offset combined offset of server relative to this host
frequency frequency drift (PPM) relative to hardware clock
combined system jitter
clock frequency wander (PPM)
tai TAI-UTC offset (s)
leapsec NTP seconds when the next leap second is/was inserted
expire NTP seconds when the NIST leapseconds file expires
The jitter and wander statistics are exponentially-weighted RMS averages. The system jitter is defined in the NTPv4 specification; the
clock jitter statistic is computed by the clock discipline module.
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 Autokey dance:
host Autokey host name for this host
ident Autokey group name for this host
flags host flags (see Autokey specification)
digest OpenSSL message digest algorithm
signature OpenSSL digest/signature scheme
update NTP seconds at last signature update
cert certificate subject, issuer and certificate flags
until NTP seconds when the certificate expires
The following peer variables appear in the readlist billboard for each association. Not all variables are displayed in some configura-
associd association id
srcadr source (remote) IP address
srcport source (remote) port
dstadr destination (local) IP address
dstport destination (local) port
leap leap indicator (0-3)
stratum stratum (0-15)
precision precision (log2 s)
rootdelay total roundtrip delay to the primary reference clock
rootdisp total root dispersion to the primary reference clock
refid reference id or
reftime reference time
rec last packet received time
reach reach register (octal)
unreach unreach counter
hmode host mode (1-6)
pmode peer mode (1-5)
hpoll host poll exponent (log2 s) (3-17)
ppoll peer poll exponent (log2 s) (3-17)
headway headway (see
keyid symmetric key id
offset filter offset
delay filter delay
jitter filter jitter
bias unicast/broadcast bias
xleave interleave delay (see
The bias variable is calculated when the first broadcast packet is received after the calibration volley. It represents the offset of the
broadcast subgraph relative to the unicast subgraph. The xleave variable appears only for the interleaved symmetric and interleaved modes.
It represents the internal queuing, buffering and transmission delays for the preceding packet.
When the NTPv4 daemon is compiled with the OpenSSL software library, additional peer variables are displayed, including the following:
flags peer flags (see Autokey specification)
host Autokey server name
flags peer flags (see Autokey specification)
signature OpenSSL digest/signature scheme
initial key id
initkey initial key index
timestamp Autokey signature timestamp
ident Autokey group name for this association
The following clock variables appear in the clocklist billboard for each association with a reference clock. Not all variables are dis-
played in some configurations.
associd association id
device device description
timecode ASCII time code string (specific to device)
poll poll messages sent
noreply no reply
badformat bad format
baddata bad date or time
fudge time 1
fudge time 2
stratum driver stratum
refid driver reference id
flags driver flags
Force IPv4 name resolution. This option must not appear in combination with any of the following options: ipv6.
Force resolution of following host names on the command line to the IPv4 namespace.
Force IPv6 name resolution. This option must not appear in combination with any of the following options: ipv4.
Force 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 command and is added to the list of commands to be executed on the
Increase debug verbosity level. This option may appear an unlimited 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
Force ntpq to operate in interactive mode. This option must not appear in combination with any of the following options: command,
Force ntpq to operate in interactive mode. Prompts will be written to the standard output and commands read from the standard
numeric host addresses.
Output all host addresses in dotted-quad numeric format rather than converting to the canonical host names.
Always output status line with readvar.
By default, ntpq now suppresses the associd=... line that precedes the output of readvar (alias rv) when a single variable is
requested, such as ntpq -c "rv 0 offset". This option causes ntpq to include both lines of output for a single-variable readvar.
Using an environment variable to preset this option in a script will enable both older and newer ntpq to behave identically in this
Print a list of the peers. This option must not appear in combination with any of the following options: interactive.
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
-r keyword, --refid=keyword
Set default display type for S2+ refids. This option takes a keyword as its argument. The argument sets an enumeration value that
can be tested by comparing them against the option value macro. The available keywords are:
or their numeric equivalent.
The default keyword for this option is:
Set the default display format for S2+ refids.
Display the full 'remote' value.
Display the full value of the 'remote' value. If this requires more than 15 characters, display the full value, emit a newline, and
continue the data display properly indented on the next line.
Display usage information and exit.
Pass the extended usage information through a pager.
-> [cfgfile], --save-opts [=cfgfile]
Save the option state to cfgfile. The default is the last configuration 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 han-
dled early, out of order.
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.
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 environment variables named:
NTPQ_<option-name> or NTPQ
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.
See OPTION PRESETS for configuration environment variables.
See OPTION PRESETS for configuration files.
One of the following exit values will be returned:
Successful program execution.
The operation failed or the command syntax was not valid.
A specified configuration file could not be loaded.
libopts had an internal operational error. Please report it to email@example.com. Thank you.
The University of Delaware and Network Time Foundation
Copyright (C) 1992-2017 The University of Delaware and Network Time Foundation all rights reserved. This program is released under the
terms of the NTP license, <http://ntp.org/license>.
Please send bug reports to: http://bugs.ntp.org, firstname.lastname@example.org
This manual page was AutoGen-erated from the ntpq option definitions.
4.2.8p13 20 Feb 2019 ntpq(1)