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ntp 4.2.6p5

    1: -------------
    2: INTRODUCTION:
    3: -------------
    4: Last revision:  06-Jul-1994
    5: 
    6: Included in this distribution of XNTP V3 is a configuration file suitable
    7: for use under Apple's A/UX Version 3.x.x  There is also one for A/UX 2.0.1
    8: but it has not been fully tested. To make the executables follow the steps
    9: outlined below.
   10: 
   11: *** NOTE:  You must have gcc installed to successfully compile the current
   12: distribution; the native cc supplied with A/UX will NOT correctly compile
   13: this source.  See the FAQ in comp.unix.aux for places to obtain gcc from
   14: and how to install it.
   15: 
   16: ----------------------
   17: MAKING XNTPD FOR A/UX:
   18: ----------------------
   19: 
   20: First, you need to create the makefiles (after you've downloaded the
   21: source, of course):
   22: 
   23:     % make clean
   24:     % make refconf
   25: 
   26: After that, you should edit Config.local to make sure that BINDIR is
   27: correct for where you wish the programs to be "installed". The default
   28: (and what I use) is /usr/local/etc. Make sure that DEFS_LOCAL and
   29: CLOCKDEFS are commented out! Presently, only the LOCAL_CLOCK/REFCLOCK
   30: clock is used and supported.
   31: 
   32: 
   33: After this is done (you should be told that your system is A/UX 3), make
   34: 'xntpd' (the options to 'gcc' are held in compilers/aux3.gcc):
   35: 
   36:     % make
   37: 
   38: I do not normally use the `make install' option and so have not verified its
   39: compatibility with A/UX.  Rather, I pull out each of the executables and
   40: place them in the locally appropriate locations.
   41: 
   42: ---------------
   43: STARTING XNTPD:
   44: ---------------
   45: 
   46: At this point you need to set things up so that 'xntpd' is started upon
   47: boot-up. You can do this in 1 of 2 ways: either add entries in /etc/inittab
   48: or, more ideally, create and use an /etc/rc.local file. Since rc.local is
   49: what I recommend, here's how you do it:
   50: 
   51: By default, A/UX doesn't have rc.local, so you'll need to add the following to
   52: /etc/inittab:
   53: 
   54:     net6:2:wait:/etc/syslogd		# set to "wait" to run a syslog daemon
   55: +   jmj0:2:wait:/etc/rc.local 1>/dev/syscon 2>&1	# Local stuff
   56:     dbg2::wait:/etc/telinit v	# turn off init's verbose mode
   57: 
   58: Now, the look of a sample /etc/rc.local is as follows:
   59: 
   60:     #!/bin/sh
   61:     :
   62:     : rc.local
   63:     :
   64:     #	@(#)Copyright Apple Computer 1987	Version 1.17 of rc.sh on 91/11/08 15:56:21 (ATT 1.12)
   65:     
   66:     
   67:     #	Push line discipline/set the device so it will print
   68:     /etc/line_sane 1
   69:     echo " "
   70:     echo "Entering rc.local..."
   71:     
   72:     set `/bin/who -r`
   73:     if [ "$7" = 2 ]
   74:     then
   75:         /bin/echo " now setting the time..."
   76:         /usr/local/etc/ntpdate -s -b <host.domain>
   77:         sleep 5
   78:     #
   79:     # start up 'xntpd' if we want
   80:     #
   81:         if [ -f /etc/ntp.conf ]
   82:         then
   83:     	/bin/echo " setting tick and tickadj..."
   84:     	/usr/local/etc/tickadj -t 16672 -a 54
   85:     	sleep 5
   86:     	/bin/echo " starting xntpd..."
   87:     	/usr/local/etc/xntpd <&- > /dev/null 2>&1
   88:     	sleep 5
   89:         fi
   90:     #
   91:     fi
   92:     
   93:     echo "Leaving rc.local..."
   94: 
   95: There are a few things to notice about the above:
   96: 
   97:     o When run, 'ntpdate' forces your clock to the time returned by the
   98:       host(s) specified by <host.domain> (you'll need to replace this
   99:       be the IP address(es) of your timehosts. This is good since it gets
  100:       things close to start off with. You can use more than one time
  101:       server.
  102: 
  103:     o 'tickadj' is also called. This does two things: changes the
  104:       default value of 'tick' (which the the amount of time, in ms, that
  105:       is added to the clock every 1/60 seconds) and changes the value
  106:       of 'tickadj' which the the amount that is added or subtracted
  107:       from 'tickadj' when adjtime() is called.
  108: 
  109:       Now Mac clocks are pretty bad and tend to be slow. Sooo, instead of
  110:       having A/UX add the default of 16666ms every 1/60th of a second, you
  111:       may want it to add more (or less) so that it keeps better time. The
  112:       above value works for me but your "best" value may be different and
  113:       will likely require some fooling around to find the best value. As a
  114:       general rule of thumb, if you see 'xntpd' make a lot of negative clock
  115:       adjustments, then your clock is fast and you'll need to _decrease_
  116:       the value of 'tick'. If your adjustments are positive, then you need
  117:       to increase 'tick'. To make a guess on how fast/slow your clock is,
  118:       use 'ntpdate' to sync your clock. Now watch 'xntpd' and see how it
  119:       operates. If, for example, it resets your clock by 1 second every 30
  120:       minutes, then your clock is (1/(30*60)) is about 0.056% off and you'll
  121:       need to adjust 'tick' by 16666*0.00056 or about 9 (i.e. 'tick' should
  122:       be ~16675 if slow or ~16657 if fast)
  123: 
  124:       A/UX's default value of 'tickadj' is 1666 which is too big for
  125:       'xntpd'... so it also needs to be adjusted. I like using larger
  126:       values then the recommended value of 9 for 'tickadj' (although not
  127:       anything near as big as 1666) since this allows for quick slews
  128:       when adjusting the clock. Even with semi-large values of 'tickadj'
  129:       (~200), getting 5ms (1/200 s) accuracy is easy.
  130: 
  131: 
  132: Finally, before A/UX and 'xntpd' will work happily together, you need to
  133: patch the kernel. This is due to the fact that A/UX attempts to keep the
  134: UNIX-software clock and the Mac-hardware clock in sync. Neither the h/w or
  135: the s/w clock are too accurate. Also, 'xntpd' will be attempting to adjust
  136: the software clock as well, so having A/UX muck around with it is asking
  137: for headaches. What you therefore need to do is tell the kernel _not_ to
  138: sync the s/w clock with the h/w one. This is done using 'adb'. The
  139: following is a shell script that will do the patch for you:
  140: 
  141:     #! /bin/sh
  142:     adb -w /unix <<!
  143:     init_time_fix_timeout?4i
  144:     init_time_fix_timeout?w 0x4e75
  145:     init_time_fix_timeout?4i
  146:     $q
  147:     !
  148: 
  149: This must be done _every_ time you create a new kernel (via newconfig or
  150: newunix) or else 'xntpd' will go crazy.
  151: 
  152: --------
  153: HISTORY:
  154: --------
  155: 
  156: John Dundas was the original porter of 'xntpd' and a lot of the additions
  157: and A/UX-ports are from him. I got involved when I wanted to run 'xntpd'
  158: on jagubox. It was also around this time that the base-patchlevel of
  159: 'xntpd' changed relatively (the so-called "jones" version). Since then,
  160: I've been maintaining 'xntpd' for A/UX for the xntp development team
  161: 
  162: The original kernel patch (which patched 'time_fix_timeout') was from
  163: Richard Todd. I suggest patching 'init_time_fix_timeout' which prevents
  164: 'time_fix_timeout' from even being called.
  165: 
  166: ----------------
  167: TECHNICAL NOTES:
  168: ----------------
  169: 
  170:     o As configured (see machines/aux3), 'xntpd' will log messages via syslogd
  171:       using the LOC_LOCAL1 facility. I would suggest the following in
  172:       /etc/syslog.conf:
  173: 
  174: 	local1.notice		/usr/adm/ntpd-syslog
  175: 
  176:     o As mentioned above, the clocks on A/UX and Macs are kinda bad. Not
  177:       only that, but logging in and out of the MacOS mode as well as
  178:       extensive floppy use causes A/UX to drop and lose clock interupts
  179:       (these are sent every 1/60th of a second). So, if you do these
  180:       activities a lot, you find out that you lose about 300ms of time
  181:       (i.e., you become 300ms slow). 'xntpd' default way of handling this
  182:       is to called 'settimeofday()' and step the clock to the correct
  183:       time. I prefer having 'xntpd' slew the clock back into line by
  184:       making gradual adjustments to the clock over a coupla minutes
  185:       or so. It's for this reason that SLEWALWAYS is defined in
  186:       include/ntp_machine.h for SYS_AUX3. It's also for this reason than
  187:       I like larger values of 'tickadj'.
  188: 
  189: Good luck!  If you have problems under A/UX feel free to contact me (e-mail
  190: is preferred).
  191: --
  192:     Jim Jagielski               |  "That is no ordinary rabbit... 'tis the
  193:     jim@jagubox.gsfc.nasa.gov   |   most foul, cruel and bad-tempered
  194:     NASA/GSFC, Code 734.4       |   rodent you ever set eyes on"
  195:     Greenbelt, MD 20771         |                   Tim the Enchanter