Re: [gentoo-user] Getting a valid /etc/adjtime while using ntpd ?

[Mick]

On Friday 18 Mar 2016 09:38:50 Håkon Alstadheim wrote:
> On 03/17/2016 11:31 PM, Mick wrote:
> > On Friday 18 Mar 2016 06:01:17 Bill Kenworthy wrote:
> >> On 18/03/16 05:59, Bill Kenworthy wrote:
> >>> On 18/03/16 05:14, Alan McKinnon wrote:
> >>>> On 17/03/2016 22:02, Håkon Alstadheim wrote:
> >>>>> On 03/17/2016 02:03 PM, Bill Kenworthy wrote:
> >>>>>> On 17/03/16 20:26, Alan McKinnon wrote:
> >>>>>>> On 17/03/2016 08:50, Håkon Alstadheim wrote:
> >>>>>>>> I have a server SUPPOSED to be running 24/7, but every once in a
> >>>>>>>> while
> >>>>>>>> during a prolonged absence the box will go down. The Real Time
> >>>>>>>> Clock
> >>>>>>>> will drift, and in the rush to get the box up again I let
> >>>>>>>> everything
> >>>>>>>> boot up automatically and get both wrong time on the main systems,
> >>>>>>>> and
> >>>>>>>> different times on the various systems.
> >>>>>>>>
> >>>>>>>> My setup has a main server which does NTP, but with no direct link
> >>>>>>>> to
> >>>>>>>> the outside. Router&firewall /have/ to be booted booted later (dumb
> >>>>>>>> setup, don't ask), after which I can finally get correct time from
> >>>>>>>> NTP.
> >>>>>>>>
> >>>>>>>> NTP initiates "11 minute mode", which makes /etc/adjtime useless as
> >>>>>>>> far
> >>>>>>>> as I understand. Anybody have a /correct/ way to account for RTC
> >>>>>>>> drift
> >>>>>>>> on a box running ntpd? Right now I have a ---file in
> >>>>>>>> /etc/cron.d/time-bad like so:
> >>>>>>>> * * * * * root adjtimex -S 5 >/dev/null 2>&1 </dev/null
> >>>>>>>> ---
> >>>>>>>>
> >>>>>>>> Combined with an old-fashioned setup for hwclock during boot and
> >>>>>>>> shutdown. This feels really wrong, and I have no idea what I am
> >>>>>>>> doing.
> >>>>>>>>
> >>>>>>>> TLDR: Anybody have a /correct/ way to account for RTC drift on a
> >>>>>>>> box
> >>>>>>>> running ntpd?
> >>>
> >>> Have you looked at adjtimex ... its in portage
> >>>
> >>>  From the man page ...
> >>>
> >>> "For a standalone or intermittently connected machine, where it’s not
> >>> ossible to run ntpd, you may use adjtimex instead to correct the sys-tem
> >>> clock for systematic drift.
> >>>
> >>>         There are several ways to estimate the drift rate.  If your
> >>>
> >>> computer can be connected to the net, you might run ntpd for at least
> >>> several hours and run "adjtimex --print" to learn what values of tick
> >>> and freq it settled on.  Alternately, you could estimate values using as
> >>> a reference the CMOS clock (see the --compare and --adjust switches),
> >>> another host (see --host and --review), or some other source of time
> >>> (see --watch and --review).  You could then add a line to rc.local
> >>> invoking adjtimex, or configure /etc/init.d/adjtimex or
> >>> /etc/default/adjtimex, to set those parameters each time you reboot."
> >>>
> >>> Used it at one time for dialup which approximates your condition.
> >>>
> >>> BillK
> >>
> >> forget it ... I forgot that's where you started from ... must be getting
> >> old :(
> >
> > Nobody mentioned net-misc/chrony.  Would it be more appropriate for this
> > use case?
>
> I see it also claims to contain an ntp server. I'll check it out.

I have found that when RTC starts playing up the BIOS MoBo battery probably 
needs replacing.  Have you tried changing it/measuring its voltage?

-- 
Regards,
Mick