HP-UX Reference (11i v2 04/09) - 1M System Administration Commands N-Z (vol 4)

x
xntpd(1M) xntpd(1M)
by the daemon. If the file does not exist or this command is not given, the initial fre-
quency offset is assumed zero. In this case, it may take some hours for the frequency to
stabilize and the residual timing errors to subside.
enable authbclientmonitorpll
ppsstats
disable authbclientmonitor
pllppsstats
Provides a way to enable or disable various server options. Flags not mentioned are
unaffected. Note that all of these flags can be controlled remotely using the
xntpdc
utility program. Each of these flags is described below.
auth Enables the server to synchronize with unconfigured peers only if the peer has
been correctly authenticated using a trusted key and key identifier. The
default for this flag is disable.
bclient Enables the server to listen for a message from a broadcast or multicast
server, as in the multicastclient
command with default address. The
default for this flag is
disable.
monitor Enables the monitoring facility. See the xntpdc monlist
command for
further information (xntpdc (1M)).
pll Enables the server to adjust its local clock, with default enable. If not set, the
local clock free-runs at its intrinsic time and frequency offset. This flag is use-
ful in case the local clock is controlled by some other device or protocol and
NTP is used only to provide synchronization to other clients. In this case, the
local clock driver is used. See the Reference Clock Drivers subsection for
further information.
pps Enables the pulse-per-second (PPS) signal when frequency and time is discip-
lined by the precision time kernel modifications. The default is enable when
these modifications are available and disable otherwise.
stats Enables the statistics facility. By default this option is enabled.
Authentication Key File Format
The NTP standard specifies an extension allowing verification of the authenticity of received NTP pack-
ets, and to provide an indication of authenticity in outgoing packets. This is implemented in
xntpd
using the DES encryption algorithm. The specification allows any one of a possible 4 billion keys, num-
bered with 32 bit unsigned integers, to be used to authenticate an association. The servers involved in an
association must agree on the value of the key used to authenticate their data, though they must each
learn the key independently. The keys are standard 56 bit DES keys.
Additionally, another authentication algorithm is available which uses an MD5 message digest to com-
pute an authenticator. The length of the key or password is limited to 8 characters.
xntpd 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 of the keys numbered 1 through 15 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, type is a single character that defines the format the key is given in,
and key is the key itself.
The key may be given in one of four different formats, controlled by the type character. The four key
types, and corresponding formats, are listed following.
S The key is a 64-bit hexadecimal number in the format specified in the DES document, that is the
high order 7 bits of each octet are used to form the 56-bit key while the low order bit of each octet is
given a value such that odd parity is maintained for the octet. Leading zeroes must be specified
(that is, the key must be exactly 16 hex digits long) and odd parity must be maintained. Hence a
zero key, in standard format, would be given as 0101010101010101.
N The key is a 64-bit hexadecimal number in the format specified in the NTP standard. This is the
same as the DES format except the bits in each octet have been rotated one bit right so that the par-
ity bit is now the high order bit of the octet. Leading zeroes must be specified and odd parity must
be maintained. A zero key in NTP format would be specified as 8080808080808080.
Section 1M−−938 Hewlett-Packard Company − 3 − HP-UX 11i Version 2: September 2004