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ntp.keys(5)


NAME

   ntp.keys - NTP symmetric key file format configuration file

SYNOPSIS

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

   All arguments must be options.

DESCRIPTION

   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) page.

   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 opt_IP_list

   where keyno is a positive integer (between 1 and 65534),  type  is  the
   message digest algorithm, and key is the key itself, and opt_IP_list is
   an optional comma-separated list of IPs that are allowed to serve time.
   If opt_IP_list is empty, any properly-authenticated server message will
   be accepted.

   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).

   SHA
   SHA1
   RMD160 The key is a hex-encoded ASCII string of 40 characters, which is
          truncated as necessary.

   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.

FILES

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

SEE ALSO

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

AUTHORS

   The University of Delaware and Network Time Foundation

COPYRIGHT

   Copyright  (C)  1992-2016  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>.

BUGS

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

NOTES

   This document was derived from FreeBSD.

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



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