Provided by: ntp_4.2.8p4+dfsg-3ubuntu5_amd64 bug


       ntp.keys - NTP symmetric key file format configuration file


        [--option-name] [--option-name value]

       All arguments must be options.


       This document describes the format of an NTP symmetric key file.  For a description of the
       use of this type of file, see the "Authentication  Support"  section  of  the  ntp.conf(5)

       ntpd(8)  reads its keys from a file specified using the -k command line option or the keys
       statement in the configuration file.  While key number 0 is fixed by the NTP standard  (as
       56 zero bits) and may not be changed, one or more keys numbered between 1 and 65534 may be
       arbitrarily set in the keys file.

       The key file uses the same comment conventions as the configuration file.  Key entries use
       a fixed format of the form

           keyno type key

       where  keyno  is  a  positive  integer  (between  1 and 65534), type is the message digest
       algorithm, and key is the key itself.

       The key may be given in a format controlled by the type field.  The  type  MD5  is  always
       supported.   If  ntpd was built with the OpenSSL library then any digest library supported
       by that library may be specified.  However, if compliance with FIPS 140-2 is required  the
       type must be either SHA or SHA1.

       What follows are some key types, and corresponding formats:

       MD5    The  key  is  1 to 16 printable characters terminated by an EOL, whitespace, or a #
              (which is the "start of comment" character).

       RMD160 The key is a hex-encoded ASCII string of  40  characters,  which  is  truncated  as

       Note that the keys used by the ntpq(8) and ntpdc(8) programs are checked against passwords
       requested by the programs and entered by hand, so it is generally appropriate  to  specify
       these keys in ASCII format.


       /etc/ntp.keys the default name of the configuration file


       ntp.conf(5), ntpd(1), ntpdate(1), ntpdc(1), sntp(1)


       The University of Delaware and Network Time Foundation


       Copyright  (C) 1992-2015 The University of Delaware and Network Time Foundation all rights
       reserved.   This  program  is   released   under   the   terms   of   the   NTP   license,


       Please send bug reports to:,


       This document was derived from FreeBSD.

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