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Unix/Linux 网络时间协议版本3 Network Time Protocol Version 3 (NTP) distribution for Unix systems

This directory contains support for monitoring the local clock of xntp daemons.

WARNING: The scripts and routines contained in this directory are bete realease!
	 Do not depend on their correct operation. They are, however, in regular
	 use at University of Erlangen-Nuernberg. No severe problems are known
	 for this code.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
PLEASE THINK TWICE BEFORE STARTING MONITORING REMOTE XNTP DEAMONS !!!!
MONITORING MAY INCREASE THE LOAD OF THE DEAMON MONITORED AND MAY
INCREASE THE NETWORK LOAD SIGNIFICANTLY 
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


Files are:

README:
	This file

ntptrap:
	perl script to log ntp mode 6 trap messages.

	It sends a set_trap request to each server given and dumps the
	trap messages received. It handles refresh of set_trap.
	Currently it handles only NTP V2, however the NTP V3 servers
	also accept v2 requests. It will not interpret v3 system and peer
	stati correctly.

	usage:
	  ntptrap [-n] [-p <port>] [-l <debug-output>] servers...
	
	-n:		do not send set_trap requests

	port:		port to listen for responses
			useful if you have a configured trap

	debug-output:	file to write trace output to (for debugging)

	This script convinced me that ntp trap messages are only of
	little use.

ntploopstat:
	perl script to gather loop info statistics from xntpd via mode 7
	LOOP_INFO requests.

	This script collects data to allow monitoring of remote xntp servers
	where it is not possible to directly access the loopstats file
	produced by xntpd itself. Of course, it can be used to sample
	a local server if it is not configured to produce a loopstats file.

	Please note, this program poses a high load on the server as
	a communication takes place every delay seconds ! USE WITH CARE !

	usage:
	  ntploopstat [-d<delay>] [-t<timeout>] [-l <logfile>] [-v] [ntpserver]
	
	delay:		number of seconds to wait between samples
			default: 60 seconds
	timeout:	number of seconds to wait for reply
			default 12 seconds
	logfile:	file to log samples to
			default: loopstats:<ntpserver>:
			(note the trailing colon)
			This name actually is a prefix.
			The file name is dynamically derived by appending
			the name of the month the sample belongs to.
			Thus all samples of a month end up in the same file.

	the format of the files generated is identical to the format used by
	xntpd with the loopstats file:
		MJD <seconds since midnight UTC> offset frequency compliance
	
	if a timeout occurs the next sample is tried after delay/2 seconds

	The script will terminate after MAX_FAIL (currently 60) consecutive errors.
	Errors are counted for:
		- error on send call
		- error on select call
		- error on recv call
		- short packet received
		- bad packet 
		- error on open for logfile

ntploopwatch:
	perl script to display loop filter statistics collected by ntploopstat
	or dumped directly by xntpd.

	Gnuplot is used to produce a graphical representation of the sample
	values, that have been preprocessed and analysed by this script.

	It can either be called to produce a printout of specific data set or
	used to continously monitor the values. Monitoring is achieved by 
	periodically reprocessing the logfiles, which are updated regularly
	either by a running ntploopstat process or by the running xntpd.

	usage:
	  to watch statistics permanently:
	     ntploopwatch [-v[<level>]] [-c <config-file>] [-d <working-dir>]

	  to get a single print out specify also
			  -P<printer> [-s<samples>]
				      [-S <start-time>] [-E <end-time>]
				      [-O <MaxOffs>] [-o <MinOffs>]
	
	level:		level of verbosity for debugging
	config-file:	file to read configurable settings from
			On each iteration it is checked and reread
			if it has been changed
			default: loopwatch.config
	working-dir:	specify working directory for process, affects
			interpretation of relative file names
	
	All other flags are only useful with printing plots, as otherwise
	command line values would be replaced by settings from the config file.

	printer:	specify printer to print plot
			BSD print systems semantics apply; if printer is omitted
			the name "ps" is used; plots are prepared using
			PostScript, thus the printer should best accept
			postscript input

	For the following see also the comments in loopwatch.config.SAMPLE

	samples:	use last # samples from input data
	start-time:	ignore input samples before this date
	end-time:	ignore input samples after this date
			if both start-time and end-time are specified
			a given samples value is ignored
	MaxOffs:
	MinOffs:	restrict value range 

loopwatch.config.SAMPLE:
	sample config file for ntploopwatch
	each configurable option is explained there

lr.pl:
	linear regression package used by ntploopwatch to compute
	linear approximations for frequency and offset values
	within display range

timelocal.pl:
	used during conversion of ISO_DATE_TIME values specified in loopwatch
	config files to unix epoch values (seconds since 1970-01-01_00:00_00 UTC)

	A version of this file is distributed with perl-4.x, however,
	it has a bug related to dates crossing 1970, causing endless loops..
	The version contained here has been fixed.

ntp.pl:
	perl support for ntp v2 mode 6 message handling
	WARNING: This code is beta level - it triggers a memory leak;
		 as for now it is not quite clear, wether this is caused by a
		 bug in perl or by bad usage of perl within this script.