what was up with ntp again?

[Mike Alexander]

On 23 Mar 2015, at 14:36, Mihai Moldovan wrote:

> On 23.03.2015 07:27 PM, Christopher Jones wrote:
>>> On 23 Mar 2015, at 6:24pm, Mihai Moldovan <ionic at macports.org> 
>>> wrote:
>>> You likely rebooted yesterday or the like.
>>>
>>> I haven't done so on a while, obviously…
>>
>> yes, I did reboot around then yesterday. Perhaps I mis understood 
>> [Brandon]’s mail though but that seemed to suggest even a reboot 
>> wouldn’t update it. But if it does then fine, (non)mystery 
>> solved…
>
> That's just a misunderstanding. The file is created/updated once
> whenever Apple's ntpd starts, but never touched again afterwards 
> (until
> the next time Apple's ntpd is started.)
>
> It's not a "once in a lifetime" deal.
>
> So, his explanation fits beautifully.

I have a feeling that this has changed recently, perhaps as part of 
Apple's NTP security update. [1]  On two of my machines, both running 
stock Apple code in this regard, /var/db/ntp.drift is changed between 
boots (it changed while I was looking at it just now on one machine).  
Also pacemaker is not running on either machine (it's disabled in 
launchctl).  I don't know why my machines are different than yours, but 
it's not because of anything I intentionally changed.  I see that ntpd 
on these machines is version 92.10.1 which is even later than in that 
security update.  This was apparently part of 10.10.2.  On one of the 
machines I looked at /usr/libexec/pacemaker was last accessed on Feb. 17 
even though the machine was booted several times since then.

                Mike

[1] <https://support.apple.com/en-us/HT204425>