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NTPQ

Section: Programmer's Manual (1)
Updated: 2007-03-07
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NAME

ntpq - standard NTP query program  

SYNOPSIS

ntpq [-flag [value]]... [--opt-name [[=| ]value]]...
[ host ...]  

DESCRIPTION

This manual page documents, briefly, the ntpq command. The [= prog-name =] 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 [= prog-name =] 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 [= prog-name =] 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, [= prog-name =] 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 [= prog-name =] utility will prompt for commands if the standard input is a terminal device.

The [= prog-name =] 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 [= prog-name =] 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, [= prog-name =] 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 [= prog-name =] utility itself and do not result in NTP mode 6 requests being sent to a server. These are described following.

? [command_keyword]

A `?' by itself will print a list of all the command keywords known to this incarnation of [= prog-name =] . 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 [= prog-name =] 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 [= prog-name =] utility maintains an internal list in which data to be included in control messages can be assembled, and sent using the readlist and writelist commands described below. The addvars command allows variables and their optional values to be added to the list. If more than one variable is to be added, the list should be comma-separated and not contain white space. The rmvars command can be used to remove individual variables from the list, while the clearlist command removes all variables from the list.

authenticate [ yes | no ] Normally [= prog-name =] does not authenticate requests unless they are write requests. The command `authenticate' yes causes [= prog-name =] 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 [= prog-name =] to display whether or not [= prog-name =] is currently autheinticating requests.

cooked Causes output from query commands to be "cooked", so that variables which are recognized by [= prog-name =] will have their values reformatted for human consumption. Variables which [= prog-name =] thinks should have a decodable value but didn't are marked with a trailing `?' 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.

host hostname Set the host to which future queries will be sent. Hostname may be either a host name or a numeric address.

hostnames Cm yes | Cm 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 a key number the server has been configured to use for this purpose.

ntpversion [ 1 2 3 4 ] Sets the NTP version number which [= prog-name =] claims in packets. Defaults to 3, Note that mode 6 control messages (and modes, for that matter) didn't exist in NTP version 1. There appear to be no servers left which demand version 1. With no argument, displays the current NTP version that will be used when communicating with servers.

quit Exit [= prog-name =] .

passwd This command prompts you to type in a password (which will not be echoed) which will be used to authenticate configuration requests. The password must correspond to the key configured for use by the NTP server for this purpose if such requests are to be successful.

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

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

 

OPTIONS

-4, --ipv4
Force IPv4 DNS name resolution. This option is a member of the ipv4 class of options.

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

-6, --ipv6
Force IPv6 DNS name resolution. This option is a member of the ipv4 class of options.

Force DNS 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 specified host(s).

-d, --debug-level
Increase output debug message level. This option may appear an unlimited number of times.

Increase the debugging message output level.

-D string, --set-debug-level=string
Set the output debug message level. This option may appear an unlimited number of times.

Set the output debugging level. Can be supplied multiple times, but each overrides the previous value(s).

-p, --peers
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 command.

-i, --interactive
Force ntpq to operate in interactive mode. This option must not appear in combination with any of the following options: command, peers.

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

-n, --numeric
numeric host addresses.

Output all host addresses in dotted-quad numeric format rather than converting to the canonical host names.

-?, --help
Display usage information and exit.
-!, --more-help
Extended usage information passed thru pager.
-> [rcfile], --save-opts[=rcfile]
Save the option state to rcfile. The default is the last configuration file listed in the OPTION PRESETS section, below.
-< rcfile, --load-opts=rcfile, --no-load-opts
Load options from rcfile. The no-load-opts form will disable the loading of earlier RC/INI files. --no-load-opts is handled early, out of order.
-v [{v|c|n}], --version[={v|c|n}]
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.
 

OPTION PRESETS

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.  

AUTHOR

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

see html/copyright.html

This manual page was AutoGen-erated from the ntpq option definitions.


 

Index

NAME
SYNOPSIS
DESCRIPTION
Internal Commands
OPTIONS
OPTION PRESETS
AUTHOR




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