Hello Marc,
Wednesday, October 24, 2007, 1:13:23 PM, you wrote:
>>   May  be  it makes sense to set "-ncv" as a default behavior of rdate, but

quoted text
>> there is should be a way to synchronize time without running a demon (don't

>> understand  why  are  people  so  aggressive  about that) if you don't need

>> up-to-second  synchronization  (in my case modern hardware goes less than a

>> second off per day, and really old hardware - less than 10 seconds).

MB> You don't understand the implications of changing the time of a computer

MB> at runtime.
  I believe I do. :)

  There  are  pros  and  cons  in  the  "demon" and in the "cron" schema. I

decided  to  use  cron and I know why. Every sysadmin/architect should make

that  decision  for  *his*  systems  (and  know  why).  "Home users" should

probably  stay  with the default (ntpd), but they are usually using Windows

and cheap "hardware" firewalls anyway. ;)
MB> If  either  case is acceptable depends on the software that runs on the

MB> computer.
  Exactly.  And  I  believe  that  "usual"  case is not a cluster, monetary

transaction server or traffic control system.
MB> A  computer  that  controls  an  insulin  pump  probably  should run at

MB> constant  speed  whereas  a computer that does a task at a certain time

MB> should not skip time units.
  Have  you  seen  an  insulin  pump ran by OpenBSD system? ;) Give me some

*real* examples (if you want to).
MB> If a cronjob runs at 17:10 and at 17:00 your wise cronjob sets the time

MB> to 17:20, cron will not start that job.
  First  of  all,  this  is not a *real* case again. I was talking about 10

seconds  a  day,  not  20  minutes.  If  your *production* hardware goes 20

minutes off a day you will probably replace it (I believe, for new hardware

it's a "warranty" case).

  Second   of  all,  I've  seen  that  behavior  (with  much  smaller  time

adjustments)  on  SCO, but OpenBSD handles it pretty good - my cron doesn't

repeat itself after adjusting time back.
--

Best regards,

 Boris                            mailto:boris@twopoint.com