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

[Mick]

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?

-- 
Regards,
Mick