* Paul de Weerd <weerd@weirdnet.nl> [2007-10-24 19:28]:
quoted text
> On Wed, Oct 24, 2007 at 10:47:45AM -0500, Boris Goldberg wrote:
> |   May  be  it makes sense to set "-ncv" as a default behavior of rdate, but
> | 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).
> 
> The problem here is the jump in time. You repeat a second or more (if
> you have to jump back) or skip some (if you jump forward). This may
> not be a problem for you in particular, but is considered bad in
> general.

rdate can use adjtime, so that point is moot.

quoted text
> Another issue is the fact that the server you're syncing to may not be
> perfectly sync'ed itself. Or maybe there's some (assymmetrical) delay
> in the network. This may make time on your machine somewhat off (this
> isn't as big a problem as the previous, IMO).

this is the key. rdate sets/skews the clock based on a single reply. 
which might get affected badly by network issues or whatever, or be 
spoofed, or... ntpd doesn't have that problem at all - last not least it 
never uses less than 8 packets to form a single update (just picking 
that one as example, there is more it can do, because it can develop 
thing over TIME instead of a single one-shot update & exit.

and it fixes the clock frequency permanently using adjtick. rdate 
doesn't.

quoted text
> And it's totally unneccessary, simply run ntpd and be done
> with it.

exactly.

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