Re: Raspian ntp manual invocation?

From	Greg Wooledge <wooledg@eeg.ccf.org>
Newsgroups	linux.debian.user
Subject	Re: Raspian ntp manual invocation?
Date	2019-08-08 21:40 +0200
Message-ID	<ysWqu-W6-21@gated-at.bofh.it> (permalink)
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On Thu, Aug 08, 2019 at 12:28:32PM -0700, John Conover wrote:
> timedatectl(1) yields:
> 
>           Local time: Thu 2019-08-08 12:16:51 PDT
>       Universal time: Thu 2019-08-08 19:16:51 UTC
>             RTC time: n/a
>            Time zone: America/Los_Angeles (PDT, -0700)
>      Network time on: yes
>     NTP synchronized: yes
>      RTC in local TZ: no
> 
> Does this mean ntp(1) is running periodically?

More likely, it means systemd-timesyncd.service is running.

> BTW, the reason for the question is that the RPi documentation claims
> ntp(1) is run ONLY AT BOOT to set the system time.

... "the RPi documentation"?  As in hardware documentation?  How on earth
would the hardware documentation know what the operating system is going
to do?  Unless it's talking about something that happens in the firmware
before the OS is loaded.  In which case, it wouldn't be ntp(1).  The (1)
indicates a Unix command utility.  Not pieces of the firmware or whatever.

> I have a 3b+ that
> has been running many weeks with less than a 100 mS system clock
> error, implying that ntp(1) is run periodically. Hardly possible with
> commodity timing components.

ps is your friend.  Or systemctl status systemd-timesyncd.service.  Or
journalctl -u systemd-timesyncd.service.

Thread

Raspian ntp manual invocation? conover@rahul.net (John Conover) - 2019-08-08 20:20 +0200
  Re: Raspian ntp manual invocation? Gene Heskett <gheskett@shentel.net> - 2019-08-08 20:20 +0200
    Re: Raspian ntp manual invocation? Sven Joachim <svenjoac@gmx.de> - 2019-08-08 20:40 +0200
      Re: Raspian ntp manual invocation? conover@rahul.net (John Conover) - 2019-08-08 21:30 +0200
        Re: Raspian ntp manual invocation? Greg Wooledge <wooledg@eeg.ccf.org> - 2019-08-08 21:40 +0200
      Re: Raspian ntp manual invocation? "Martin McCormick" <martin.m@suddenlink.net> - 2019-08-08 21:50 +0200

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