How to coordinate the clock when dual-booting with Windows

Tue Dec 12 02:41:16 UTC 2017

On 11.12.2017 22:07, Drew Einhorn wrote:
> NTP is probably assuming system clock is UTC and correcting based on
> your time zone settings. This way ntp can assume all clocks are UTC and
> not have figure out all the relevant time zone corrections.
> 
> Does this make sense for your time zone?
> 
> Remote users can set their time zone environment variables for their
> local time zone. Things work out nicely on Unix or Linux based systems.
> 
> I don't know If there is a right way to configure Windows so it knows
> the hardware clock is UTC and the user time zone is different. If not,
> you have different issues depending on whether the hardware clock is UTC
> or local time. You may have to decide which issues are the bigger problem.
> 
> Windows may screw things up for spring and fall daylight savings
> adjustments, if Windows thinks the hardware is on local time when it's
> really on UTC.
> 
> If the latest updates are not installed, your systems may change to or
> from daylight savings on the wrong weekend. This can be an issue for all
> operating systems.
> 
> My daughter's alarm clock switched itself from daylight savings time to
> standard time on the wrong weekend this year. And, there is no way to
> update the rules for when to change.
> 
> 
> 
> On December 11, 2017, at 12:47 PM, Kevin O'Gorman <kogorman at gmail.com>
> wrote:
> 
> 
> On Sun, Dec 10, 2017 at 11:23 PM, Grizzly via ubuntu-users
> <ubuntu-users at lists.ubuntu.com <mailto:ubuntu-users at lists.ubuntu.com>>
> wrote:
> 
>     10 December 2017  at 20:41, Kevin O'Gorman wrote:
>     Re: How to coordinate the clock whe (at least in part)
> 
>     >On Sun, Dec 10, 2017 at 12:59 PM, Grizzly via ubuntu-users <
>     >ubuntu-users at lists.ubuntu.com
>     <mailto:ubuntu-users at lists.ubuntu.com>> wrote:
>     >
>     >> 10 December 2017  at 15:52, Colin Law wrote:
>     >> Re: How to coordinate the clock whe (at least in part)
>     >>
>     >> >On 10 December 2017 at 15:45, Liam Proven <lproven at gmail.com <mailto:lproven at gmail.com>> wrote:
>     >> >
>     >> >> On 10 December 2017 at 10:42, Colin Law <clanlaw at gmail.com <mailto:clanlaw at gmail.com>> wrote:
>     >> >> >
>     >> >> > The clock is not normally an issue when dual booting.
>     >> >>
>     >> >> It bally well is for me!
>     >> >>
>     >> >> E.g. if it's set to local time, both OSes move the system clock
>     >> >> forward or backwards when daylight savings times begins or ends,
>     >> >> resulting in a 2h discrepancy.
>     >> >>
>     >> >> My solution: minimize use of Windows. I boot it a couple of times a
>     >> >> year, if that, normally.
>     >> >>
>     >> >
>     >> >Interesting, I have never seen that. I assumed the system clock was in
>     >> UTC,
>     >> >and so would not change with DST.  You may be right about that though, I
>     >> >have no evidence either way. However I would have thought it would re-sync
>     >> >the next time ntpdate or whatever it is that does the auto timesync ran.
> 
>     >> Its on a tab in date/time that not many people visit, default is off
> 
>     >> That's what I was hoping, but I cannot find anything about NTP in my
>     >Windows 10.
> 
>     Must admit I was unsure if the same controls carry forward to later
>     windoz, (I
>     stopped at Win7) it looks like they do
> 
>     https://www.isunshare.com/windows-10/2-ways-to-change-date-and-time-on-windows-1
>     0.html
>     <https://www.isunshare.com/windows-10/2-ways-to-change-date-and-time-on-windows-1%0A0.html>
> 
>     only difference appears that you only see the internet time when you
>     click
>     "Change date time"
> 
>     here it (now) has a number of possible time server, IIRC it came
>     with only two
>     (unreliable), the rest I added later
> 
>     there is a reg entry
> 
>     [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\DateTime\Servers]
>     @="3"
>     "1"="time.windows.com <http://time.windows.com>"
>     "2"="129.6.15.29 <http://129.6.15.29>"
>     "3"="0.uk.pool.ntp.org <http://0.uk.pool.ntp.org>"
>     "4"="1.uk.pool.ntp.org <http://1.uk.pool.ntp.org>"
>     "6"="ntp2b.mcc.ac.uk <http://ntp2b.mcc.ac.uk>"
>     "5"="ntp2a.mcc.ac.uk <http://ntp2a.mcc.ac.uk>"
>     "7"="ntp2c.mcc.ac.uk <http://ntp2c.mcc.ac.uk>"
>     "8"="ntp2d.mcc.ac.uk <http://ntp2d.mcc.ac.uk>"
>     "9"="ntp.exnet.com <http://ntp.exnet.com>"
> 
>     the chosen NTP server does propagate to other Reg entries
> 
>     but you can manually add direct in the dialogue if you don't want to
>     delve in
>     Registry
> 
> 
> This is interesting, but I'm uncertain how to use it.  I found the list
> of servers in the registry.  I didn't put them there, but there are 5,
> and number 5 appears as the default.  It is time-b.nist.gov
> <http://time-b.nist.gov> which I sure hope is not unreliable.  However,
> I still get Windows showing the time off by 8 hours when it boots up,
> and I'm supposing that's because it is using the time in the BIOS DRAM,
> but I'm unsure because as near as I can tell the BIOS is set to local
> time; at least that's what I see when I'm in BIOS setup.  Frankly I'm
> all confused.
> 
> It would be nice if Windows would use nist.gov <http://nist.gov> and
> apply the timezone, ignoring BIOS completely.
> 
> -- 
> Kevin O'Gorman
> #define QUESTION ((bb) || (!bb))   /* Shakespeare */
> 
> 	Please consider the environment before printing this email.

Hi!

Could it be that You did not even think of trying to use a search engine
for your problem?

So, i'm a nice guy and did just one little search [coordinate time dual
boot system windows linux] and will paste You _some_ not even all of the
links i found obviously quite fitting to Your question:

http://ubuntuhandbook.org/index.php/2016/05/time-differences-ubuntu-1604-windows-10/

https://askubuntu.com/questions/800914/clock-shows-wrong-time-after-switching-from-ubuntu-to-windows-10

https://askubuntu.com/questions/169376/clock-time-is-off-on-dual-boot

http://www.webupd8.org/2014/09/dual-boot-fix-time-differences-between.html

https://www.ghacks.net/2017/07/30/fixing-incorrect-clock-time-settings-while-dual-booting-windowslinux/

https://lifehacker.com/5742148/fix-windows-clock-issues-when-dual-booting-with-os-x

https://www.howtogeek.com/211144/how-to-get-windows-and-linux-clocks-to-display-the-correct-and-matching-time-dual-boot/

https://www.youtube.com/watch?v=Gqre5fRo704

https://techlr.de/dual-boot-windows-10-und-linux-falsche-uhrzeit/

I'm pretty sure the information You asked for is hidden somewhere in
these links ...! ;-)

Hope i did You a little favor!

Good luck!

J. L.