ntpq: Network Time Protocol Query User's Manual

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ntpq: Network Time Protocol Query User Manual

The ntpq utility program is used to monitor the operational status and determine the performance of ntpd, the NTP daemon.

This document applies to version 4.2.8p9 of ntpq.


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Description

The ntpq utility program is used to monitor NTP daemon ntpd 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 variable names 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 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. ntpq will prompt for commands if the standard input is a terminal device.

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. ntpq 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 DNS resolution to the IPv4 namespace, while a -6 qualifier forces DNS resolution to the IPv6 namespace.

For examples and usage, see the NTP Debugging Techniques page.



Invoking ntpq

The ntpq utility program is used to query NTP servers which implement the standard NTP mode 6 control message formats defined in Appendix B of the NTPv3 specification RFC1305, requesting information about current state and/or changes in that state. 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 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 terminal device.

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.

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.

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
showvars
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. The showvars command displays the current list of optional variables.
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 differently, and can occasionally melt the CPU in fuzzballs if you turn authentication on before doing a peer display. The command authenticate causes ntpq to display whether or not ntpq is currently autheinticating 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 thinks should have a decodable value but didn't are marked with a trailing ?.
debug [more | less | off]
With no argument, displays the current debug level. Otherwise, the debug level is changed to the indicated level.
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.
exit
Exit ntpq
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 allows the specification of a key number to be used to authenticate configuration requests. This must correspond to the controlkey key number the server has been configured to use for this purpose.
keytype [md5 | OpenSSLDigestType]
Specify the type of key to use for authenticating requests. md5 is alway supported. If ntpq was built with OpenSSL support, any digest type supported by OpenSSL can also be provided. If no argument is given, the current keytype is displayed.
ntpversion [1 | 2 | 3 | 4]
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 argument, 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
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.
version
Print 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 mode-6 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.

associations
Display a list of mobilized associations in the form:
          ind assid status conf reach auth condition last_event cnt
     
Sy String Ta Sy Description
ind Ta index on this list
assid Ta association ID
status Ta peer status word
conf Ta yes: persistent, no: ephemeral
reach Ta yes: reachable, no: unreachable
auth Ta ok, yes, bad and none
condition Ta selection status (see the select field of the peer status word)
last_event Ta event report (see the event field of the peer status word)
cnt Ta event count (see the count field of the peer status word)

authinfo
Display the authentication statistics.
clockvar assocID [name[=value]] [...]
cv assocID [name[=value]] [...]
Display a list of clock variables for those associations supporting a reference clock.
:config [...]
Send the remainder of the command line, including whitespace, to the server as a run-time configuration command in the same format as a line in the configuration file. This command is experimental until further notice and clarification. Authentication is of course required.
config-from-file filename
Send the each line of filename to the server as run-time configuration commands in the same format as a line in the configuration file. This command is experimental until further notice and clarification. Authentication is required.
ifstats
Display statistics for each local network address. Authentication is required.
iostats
Display network and reference clock I/O statistics.
kerninfo
Display kernel loop and PPS statistics. As with other ntpq output, times are in milliseconds. The precision value displayed is in milliseconds as well, unlike the precision system variable.
lassociations
Perform the same function as the associations command, except display mobilized and unmobilized associations.
lopeers [-4 | -6]
Obtain and print a list of all peers and clients showing dstadr (associated with any given IP version).
lpeers [-4 | -6]
Print a peer spreadsheet for the appropriate IP version(s). dstadr (associated with any given IP version).
monstats
Display monitor facility statistics.
mrulist [limited | kod | mincount=count | laddr=localaddr | sort=sortorder | resany=hexmask | resall=hexmask]
Obtain and print traffic counts collected and maintained by the monitor facility. With the exception of sort=sortorder, the options filter the list returned by ntpd. 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 mincount=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 any of addr, count, avgint, lstint, or any of those preceded by a minus sign (hyphen) to reverse the sort order. The output columns are:
Column
Description
lstint
Interval in s 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 response.
r
Rate control indicator, either a period, L or K for no rate control response, rate limiting by discarding, or rate limiting 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.
remote address
DNS name, numeric address, or address followed by claimed DNS name which could not be verified in parentheses.

mreadvar assocID assocID [variable_name[=value] ...]
mrv assocID assocID [variable_name[=value] ...]
Perform the same function as the readvar command, except for a range of association IDs. This range is determined from the association list cached by the most recent associations command.
opeers [-4 | -6]
Obtain and print the old-style list of all peers and clients showing dstadr (associated with any given IP version), rather than the refid.
passociations
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]remote refid st t when pool reach delay offset jitter
     
Variable
Description
[tally]
single-character code indicating current value of the select field of the .Lk decode.html#peer "peer status word"
remote
host name (or IP number) of peer. The value displayed will be truncated to 15 characters unless the -w flag is given, in which case the full value will be displayed on the first line, and the remaining data is displayed on the next line.
refid
association ID or .Lk decode.html#kiss "'kiss code"
st
stratum
t
u: unicast or manycast client, b: broadcast or multicast client, l: local (reference clock), s: symmetric (peer), A: manycast server, B: broadcast server, M: multicast server
when
sec/min/hr since last received packet
poll
poll interval (log2 s)
reach
reach shift register (octal)
delay
roundtrip delay
offset
offset of server relative to this host
jitter
jitter

apeers
Display a list of peers in the form:
          [tally]remote refid assid st t when pool reach delay offset jitter
     

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.

pstats assocID
Show the statistics for the peer with the given assocID.
readlist assocID
rl assocID
Read the system or peer variables included in the variable list.
readvar assocID name[=value] [, ...]
rv assocID name[=value] [, ...]
Display the specified variables. If 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 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 zero. Multiple names are specified with comma separators and without whitespace. Note that time values are represented in milliseconds and frequency values in parts-per-million (PPM). Some NTP timestamps are represented in the format YYYYMMDDTTTT , where YYYY is the year, MM the month of year, DD the day of month and TTTT the time of day.

reslist
Show the access control (restrict) list for ntpq
saveconfig filename
Write the current configuration, including any runtime modifications given with :config or config-from-file, to the ntpd host's file filename. This command will be rejected by the server unless .Lk miscopt.html#saveconfigdir "saveconfigdir" appears in the ntpd configuration file. filename can use strftime() format specifies to substitute the current date and time, for example, q]saveconfig ntp-%Y%m%d-%H%M%S.confq]. The filename used is stored in system variable savedconfig. Authentication is required.
timerstats
Display interval timer counters.
writelist assocID
Write the system or peer variables included in the variable list.
writevar assocID name=value [, ...]
Write the specified variables. 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 spaces.
sysinfo
Display operational summary.
sysstats
Print statistics counters maintained in the protocol module.
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 available on a per-association basis. These words are displayed in the rv and as commands both in hexadecimal and in decoded short tip strings. The codes, tips and short explanations are documented on the .Lk decode.html "Event Messages and Status Words" 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 .Lk decode.html#kiss "kiss codes" . The original purpose 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.

System Variables

The following system variables appear in the rv billboard. Not all variables are displayed in some configurations.

Variable
Description
status
.Lk decode.html#sys "system status word"
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
peer
system peer association ID
tc
time constant and poll exponent (log2 s) (3-17)
mintc
minimum time constant (log2 s) (3-10)
clock
date and time of day
refid
reference ID or .Lk decode.html#kiss "kiss code"
reftime
reference time
offset
combined offset of server relative to this host
sys_jitter
combined system jitter
frequency
frequency offset (PPM) relative to hardware clock
clk_wander
clock frequency wander (PPM)
clk_jitter
clock jitter
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:

Variable
Description
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
Peer Variables

The following peer variables appear in the rv billboard for each association. Not all variables are displayed in some configurations.

Variable
Description
associd
association ID
status
.Lk decode.html#peer "peer status word"
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 .Lk decode.html#kiss "kiss code"
reftime
reference 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 .Lk rate.html "Rate Management and the Kiss-o'-Death Packet" )
flash
.Lk decode.html#flash "flash status word"
offset
filter offset
delay
filter delay
dispersion
filter dispersion
jitter
filter jitter
ident
Autokey group name for this association
bias
unicast/broadcast bias
xleave
interleave delay (see .Lk xleave.html "NTP Interleaved Modes" )
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:

Variable
Description
flags
peer flags (see Autokey specification)
host
Autokey server name
flags
peer flags (see Autokey specification)
signature
OpenSSL digest/signature scheme
initsequence
initial key ID
initkey
initial key index
timestamp
Autokey signature timestamp
Clock Variables

The following clock variables appear in the cv billboard for each association with a reference clock. Not all variables are displayed in some configurations.

Variable
Description
associd
association ID
status
.Lk decode.html#clock "clock status word"
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
fudgetime1
fudge time 1
fudgetime2
fudge time 2
stratum
driver stratum
refid
driver reference ID
flags
driver flags

This section was generated by AutoGen, using the agtexi-cmd template and the option descriptions for the ntpq program. This software is released under the NTP license, <http://ntp.org/license>.


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ntpq help/usage (--help)

This is the automatically generated usage text for ntpq.

The text printed is the same whether selected with the help option (--help) or the more-help option (--more-help). more-help will print the usage text by passing it through a pager program. more-help is disabled on platforms without a working fork(2) function. The PAGER environment variable is used to select the program, defaulting to more. Both will exit with a status code of 0.

ntpq - standard NTP query program - Ver. 4.2.8p9-RC
Usage:  ntpq [ -<flag> [<val>] | --<name>[{=| }<val>] ]... [ host ...]
  Flg Arg Option-Name    Description
   -4 no  ipv4           Force IPv4 DNS name resolution
                                - prohibits the option 'ipv6'
   -6 no  ipv6           Force IPv6 DNS name resolution
                                - prohibits the option 'ipv4'
   -c Str command        run a command and exit
                                - may appear multiple times
   -d no  debug-level    Increase debug verbosity level
                                - may appear multiple times
   -D Num set-debug-level Set the debug verbosity level
                                - may appear multiple times
   -i no  interactive    Force ntpq to operate in interactive mode
                                - prohibits these options:
                                command
                                peers
   -n no  numeric        numeric host addresses
      no  old-rv         Always output status line with readvar
   -p no  peers          Print a list of the peers
                                - prohibits the option 'interactive'
   -r KWd refid          Set default display type for S2+ refids
   -w no  wide           Display the full 'remote' value
      opt version        output version information and exit
   -? no  help           display extended usage information and exit
   -! no  more-help      extended usage information passed thru pager
   -> opt save-opts      save the option state to a config file
   -< Str load-opts      load options from a config file
                                - disabled as '--no-load-opts'
                                - may appear multiple times

Options are specified by doubled hyphens and their name or by a single
hyphen and the flag character.

The following option preset mechanisms are supported:
 - reading file $HOME/.ntprc
 - reading file ./.ntprc
 - examining environment variables named NTPQ_*

The valid "refid" option keywords are:
  hash ipv4
  or an integer from 0 through 1

Please send bug reports to:  <http://bugs.ntp.org, bugs@ntp.org>


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ipv4 option (-4)

This is the “force ipv4 dns name resolution” option.

This option has some usage constraints. It:

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


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ipv6 option (-6)

This is the “force ipv6 dns name resolution” option.

This option has some usage constraints. It:

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


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command option (-c)

This is the “run a command and exit” option. This option takes a string argument cmd.

This option has some usage constraints. It:

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).


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interactive option (-i)

This is the “force ntpq to operate in interactive mode” option.

This option has some usage constraints. It:

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


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numeric option (-n)

This is the “numeric host addresses” option. Output all host addresses in dotted-quad numeric format rather than converting to the canonical host names.


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old-rv option

This is the “always output status line with readvar” option. 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 regard.


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peers option (-p)

This is the “print a list of the peers” option.

This option has some usage constraints. It:

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.


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refid option (-r)

This is the “set default display type for s2+ refids” option. This option takes a keyword argument.

This option has some usage constraints. It:

Set the default display format for S2+ refids.


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wide option (-w)

This is the “display the full 'remote' value” option. 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.


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presetting/configuring ntpq

Any option that is not marked as not presettable may be preset by loading values from configuration ("rc" or "ini") files, and values from environment variables named NTPQ and NTPQ_<OPTION_NAME>. <OPTION_NAME> must be one of the options listed above in upper case and segmented with underscores. The NTPQ variable will be tokenized and parsed like the command line. The remaining variables are tested for existence and their values are treated like option arguments.

libopts will search in 2 places for configuration files:

The environment variables HOME, and PWD are expanded and replaced when ntpq runs. For any of these that are plain files, they are simply processed. For any that are directories, then a file named .ntprc is searched for within that directory and processed.

Configuration files may be in a wide variety of formats. The basic format is an option name followed by a value (argument) on the same line. Values may be separated from the option name with a colon, equal sign or simply white space. Values may be continued across multiple lines by escaping the newline with a backslash.

Multiple programs may also share the same initialization file. Common options are collected at the top, followed by program specific segments. The segments are separated by lines like:

    [NTPQ]

or by

    <?program ntpq>

Do not mix these styles within one configuration file.

Compound values and carefully constructed string values may also be specified using XML syntax:

    <option-name>
       <sub-opt>...&lt;...&gt;...</sub-opt>
    </option-name>

yielding an option-name.sub-opt string value of

    "...<...>..."

AutoOpts does not track suboptions. You simply note that it is a hierarchicly valued option. AutoOpts does provide a means for searching the associated name/value pair list (see: optionFindValue).

The command line options relating to configuration and/or usage help are:

version (-)

Print the program version to standard out, optionally with licensing information, then exit 0. The optional argument specifies how much licensing detail to provide. The default is to print just the version. The licensing infomation may be selected with an option argument. Only the first letter of the argument is examined:

version
Only print the version. This is the default.
copyright
Name the copyright usage licensing terms.
verbose
Print the full copyright usage licensing terms.


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ntpq exit status

One of the following exit values will be returned:

0 (EXIT_SUCCESS)
Successful program execution.
1 (EXIT_FAILURE)
The operation failed or the command syntax was not valid.
66 (EX_NOINPUT)
A specified configuration file could not be loaded.
70 (EX_SOFTWARE)
libopts had an internal operational error. Please report it to autogen-users@lists.sourceforge.net. Thank you.


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Usage

What Default Flag Option
configuration file /etc/ntp.conf -c conffile
frequency file none -f driftfile
leapseconds file none leapfile
process ID file none -p pidfile
log file system log -l logfile
include file none none includefile
statistics path /var/NTP -s statsdir
keys path /usr/local/etc -k keysdir


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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 program 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 ntpq. A ? followed by a command keyword will print function and usage information about the command.
>addvars name [ = value] [...]
rmvars name [...]
clearvars</dt>
The arguments to these commands consist of a list of items of the form name = value, where the = value is ignored, and can be omitted in read requests. ntpq 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 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
Display server messages in prettyprint format.
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 name
Set the host to which future queries will be sent. The name may be either a DNS 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 ID configured in ntp.conf for this purpose.
keytype
Specify the digest algorithm to use for authenticated requests, with default MD5. If the OpenSSL library is installed, digest can be be any message digest algorithm supported by the library. The current selections are: MD2, MD4, MD5, MDC2, RIPEMD160, SHA and SHA1.
ntpversion 1 | 2 | 3 | 4
Sets the NTP version number which ntpq claims in packets. Defaults to 2. Note that mode-6 control messages (and modes, for that matter) didn't exist in NTP version 1.
passwd
This command prompts for a password to authenticate requests. The password must correspond to the key ID configured in ntp.conf for this purpose.
quit
Exit ntpq.
raw
Display server messages as received and without reformatting.
timeout millseconds
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.


Next: , Previous: Internal Commands, Up: Top

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 mode-6 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.

associations
Display a list of mobilized associations in the form:
ind assid status conf reach auth condition last_event cnt

Variable Description


ind index on this list


assid association ID


status peer status word


conf yes: persistent, no: ephemeral


reach yes: reachable, no: unreachable


auth ok, yes, bad and none


condition selection status (see the select field of the peer status word)


last_event event report (see the event field of the peer status word)


cnt event count (see the count field of the peer status word)

clockvar assocID [name [ = value [...]] [...]]
cv assocID [name [ = value [...] ][...]]
Display a list of clock variables for those associations supporting a reference clock.
:config [...]
Send the remainder of the command line, including whitespace, to the server as a run-time configuration command in the same format as the configuration file. This command is experimental until further notice and clarification. Authentication is of course required.
config-from-file filename
Send the each line of filename to the server as run-time configuration commands in the same format as the configuration file. This command is experimental until further notice and clarification. Authentication is required.
ifstats
Display statistics for each local network address. Authentication is required.
iostats
Display network and reference clock I/O statistics.
kerninfo
Display kernel loop and PPS statistics. As with other ntpq output, times are in milliseconds. The precision value displayed is in milliseconds as well, unlike the precision system variable.
lassociations
Perform the same function as the associations command, except display mobilized and unmobilized associations.
monstats
Display monitor facility statistics.
mrulist [limited | kod | mincount=count | laddr=localaddr | sort=sortorder | resany=hexmask | resall=hexmask]
Obtain and print traffic counts collected and maintained by the monitor facility. With the exception of sort=sortorder, the options filter the list returned by ntpd. 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 mincount=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 any of addr, count, avgint, lstint, or any of those preceded by a minus sign (hyphen) to reverse the sort order. The output columns are:

Column Description


lstint Interval in s 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 response.


r Rate control indicator, either a period, L or K for no rate control response, rate limiting by discarding, or rate limiting 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.


remote address DNS name, numeric address, or address followed by claimed DNS name which could not be verified in parentheses.

mreadvar assocID assocID [ variable_name [ = value[ ... ]
mrv assocID assocID [ variable_name [ = value[ ... ]
Perform the same function as the readvar command, except for a range of association IDs. This range is determined from the association list cached by the most recent associations command.
passociations
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]remote refid st t when pool reach delay offset jitter

Variable Description
[tally] single-character code indicating current value of the select field of the peer status word.


remote host name (or IP number) of peer


refid association ID or kiss code.


st stratum


t u: unicast or manycast client, b: broadcast or multicast client, l: local (reference clock), s: symmetric (peer), A: manycast server, B: broadcast server, M: multicast server.


when sec/min/hr since last received packet


poll poll interval (log(2) s)


reach reach shift register (octal)


delay roundtrip delay


offset offset of server relative to this host


jitter jitter

readvar assocID name [ = value ] [,...]
rv assocID [ name ] [,...]
Display the specified variables. If 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 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 zero. Multiple names are specified with comma separators and without whitespace. Note that time values are represented in milliseconds and frequency values in parts-per-million (PPM). Some NTP timestamps are represented in the format YYYYMMDDTTTT, where YYYY is the year, MM the month of year, DD the day of month and TTTT the time of day.
saveconfig filename
Write the current configuration, including any runtime modifications given with :config or config-from-file, to the ntpd host's file filename. This command will be rejected by the server unless saveconfigdir appears in the ntpd configuration file. filename can use strftime() format specifiers to substitute the current date and time, for example, saveconfig ntp-%Y%m%d-%H%M%S.conf. The filename used is stored in system variable savedconfig. Authentication is required.
writevar assocID name = value [,...]
Write the specified variables. 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 spaces.
sysinfo
Display operational summary.
sysstats
Print statistics counters maintained in the protocol module.


Next: , Previous: Control Message Commands, Up: Top

Status Words and Kiss Codes

The current state of the operating program is shown in a set of status words maintained by the system and each association separately. These words are displayed in the rv and as commands both in hexadecimal and decoded short tip strings. The codes, tips and short explanations are on the Event Messages and Status Words 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 kiss codes. The original purpose 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.


Next: , Previous: Status Words and Kiss Codes, Up: Top

System Variables

The following system variables appear in the rv billboard. Not all variables are displayed in some configurations.

Variable Description


status system status word


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 (log(2) s)


rootdelay total roundtrip delay to the primary reference clock


rootdisp total dispersion to the primary reference clock


peer system peer association ID


tc time constant and poll exponent (log(2) s) (3-17)


mintc minimum time constant (log(2) s) (3-10)


clock date and time of day


refid reference ID or kiss code


reftime reference time


offset combined offset of server relative to this host


sys_jitter combined system jitter


frequency frequency offset (PPM) relative to hardware clock


clk_wander clock frequency wander (PPM)


clk_jitter clock jitter


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:

Variable Description


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


Next: , Previous: System Variables, Up: Top

Peer Variables

The following peer variables appear in the rv billboard for each association. Not all variables are displayed in some configurations.

Variable Description


associd association ID


status peer status word


srcadr
srcport source (remote) IP address and port


dstadr
dstport destination (local) IP address and port


leap leap indicator (0-3)


stratum stratum (0-15)


precision precision (log(2) s)


rootdelay total roundtrip delay to the primary reference clock


rootdisp total root dispersion to the primary reference clock


refid reference ID or kiss code


reftime reference time


reach reach register (octal)


unreach unreach counter


hmode host mode (1-6)


pmode peer mode (1-5)


hpoll host poll exponent (log(2) s) (3-17)
ppoll peer poll exponent (log(2) s) (3-17)


headway headway (see Rate Management and the Kiss-o'-Death Packet)


flash flash status word


offset filter offset


delay filter delay


dispersion filter dispersion


jitter filter jitter


ident Autokey group name for this association


bias unicast/broadcast bias


xleave interleave delay (see NTP Interleaved Modes)

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 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:

Variable Description


flags peer flags (see Autokey specification)


host Autokey server name


flags peer flags (see Autokey specification)


signature OpenSSL digest/signature scheme


initsequence initial key ID


initkey initial key index


timestamp Autokey signature timestamp


Previous: Peer Variables, Up: Top

Clock Variables

The following clock variables appear in the cv billboard for each association with a reference clock. Not all variables are displayed in some configurations.

Variable Description
associd association ID
status clock status word
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
fudgetime1 fudge time 1
fudgetime2 fudge time 2
stratum driver stratum
refid driver reference ID
flags driver flags