6.2 NTPQ

NTPQ is an interactive NTPv3 query utility to help query the status or quality of time parameters.

Usage:

NTPQ [-i np] [-c command] [host] [ ... ]

Table 6-2 NTPQ Parameters

Parameter

Description

-c

Is interpreted as an interactive format command and is added to the list of commands to be executed on the specified hosts. Multiple -c options can be given.

-i

Forces NTPQ to operate in the interactive mode. Prompts are 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 hostnames.

-p

Displays a list of the peers known to the server as well as a summary of their state.

6.2.1 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 can be sent to a file by appending a “<” followed by a filename, 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 in the following table.

Table 6-3 Parameter Description

Parameter

Description

? [ command_keyword ]

helpl [ command_keyword ]

A "?" by itself displays a list of all the command keywords known to this incarnation of NTPQ. A "?" followed by a command keyword displays the function and usage information about the command.

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. 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 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, and the clearlist command removes all variables from the list.

authenticate yes | no

Normally NTPQ does not authenticate requests unless they are write requests. The authenticate yes command causes NTPQ to send authentication with all requests it makes. Authenticated requests causes some servers to handle requests slightly differently, and the CPU is caught CPU in fuzzball (Fuzzballs are clocks that survey and average ticks from many different clocks and thereby reliable) server cycles if you turn authentication on before doing a peer display.

cooked

Causes output from query commands to be "cooked," which means that variables that are recognized by the server have their values reformatted for human consumption. Variables that NTPQ determines should have a decodeable value but didn’t 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 time stamps included in requests that require authentication. This is used to enable (unreliable) server reconfiguration over long delay network paths or between machines whose clocks are unsynchronized. However, the server does not now require time stamps in authenticated requests, so this command might be obsolete.

host hostname

Set the host to which future queries are sent. Hostname can be either a name or a numeric address.

hostnames [ yes | no ]

If Yes is specified, hostnames are printed in information displays. If No is specified, numeric addresses are displayed 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

Sets the NTP version number that NTPQ 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 that demand version 1.

quit

Exit NTPQ.

passwd

This command prompts you to type a password (which is not echoed) which is 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 to be displayed as received from the remote server. The only formatting/intepretation done on the data is to transform non-ASCII data into a printable form.

timeout millseconds

Specifies a timeout period for responses to server queries. The default is about 5000 milliseconds. Because NTPQ retries each query once after a timeout, the total waiting time for a timeout is twice the timeout value set.

6.2.2 Control Message Commands

Each peer known to an NTP server has a 16-bit integer association identifier assigned to it. NTP control messages that carry peer variables must identify the peer that the values correspond to by including its association ID. An association ID of 0 is special, and indicates that 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 sends a preprogrammed series of messages to obtain the data it needs, and the mreadlist and mreadvar commands, which iterate over a range of associations.

Table 6-4 Parameter Description

Parameter

Description

associations

Obtains and displays a list of association identifiers and peer statuses for in-spec peers of the server being queried. The list is displayed in columns. The first of these is an index numbering the associations from 1 for internal use, the second is the actual association identifier returned by the server and the third is the status word for the peer. This is followed by a number of columns containing data decoded from the status word.

The data returned by the associations command is cached internally in NTPQ. The index is then of use when dealing with servers that use association identifiers that are hard for humans to type, because for any subsequent commands that require an association identifier as an argument, the form and index can be used as an alternative.

clockvar [ assocID ] [ variable_name [ = cv [ assocID ] [ variable_name [ = value [ ... ] ] [ ... ]

Requests that a list of the server’s clock variables be sent. Servers that have a radio clock or other external synchronization respond positively to this. If the association identifier is omitted or has a value of zero, the request is for the variables of the system clock and generally gets a positive response from all servers with a clock. If the server treats clocks as pseudo-peers, so more than one clock can be connected at once, referencing the appropriate peer association ID shows the variables of a particular clock period. Omitting the variable list causes the server to return a default variable display.

lassocations

Obtains and displays 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 that retain state for out-of-spec client associations ( such as fuzzballs). Such associations are normally omitted from the display when the associations command is used, but are included in the output of lassociations.

lpassociations

Displays 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 fuzzball servers.

lpeers

Like R peers, except a summary of all associations for which the server is maintaining state is displayed. This can produce a much longer list of peers than 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 command except that it displays the internally stored data rather than making a new query.

peers

 

pstatus assocID

Sends a read status request to the server for the given association. The names and values of the peer variables returned are printed. The status word from the header is displayed preceding the variables, both in hexadecimal and in simple 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 are those of the corresponding peer. Omitting the variable list sends a request with no data that should induce the server to return a default display.

rvi index

Similar to rv with an association ID corresponding to this index.

writevar assocID variable_name [ = value ] [ ... ]

Similar to readvar request, except the specified variables are written instead of read.

writelist [ assocID ]

Similar to readlist request, except the internal list variables are written instead of read.

showipconf

Displays the IP addresses of the local machine along with the corresponding subnet broadcast addresses.