Dual Boot Messing Up My Clock ???

Megahertz07 · 31 Dec 2017

Windows does synchronize with a server and modify the RTC to local time.
Linux does the same but modify the RTC to UTC - GMT

FreeBooter · 31 Dec 2017

I think we both sticking with our own knowledge of how RTC works so there is no point for us to explain how operating systems works with RTC.

MSClin · 31 Dec 2017

Everything Megahertz07 said is true... At least read the link which Megahertz07 pointed to. I will even quote the answer from there:

If you have multiple operating systems installed in the same machine, they will all derive the current time from the same hardware clock: for this reason you must make sure that all of them see the hardware clock as providing time in the same chosen standard, or some of them will perform the time zone adjustement for the system clock, while others will not. For example, if the hardware clock was set to localtime, more than one operating system may adjust it after a DST change, thus resulting in an overcorrection; more problems may arise when travelling between different time zones and using one of the operating systems to reset the system/hardware clock.

This is the simple explanation to the problem the OP have.

lehnerus2000 · 31 Dec 2017

FreeBooter said:

Linux time configuration cannot affect time configuration of Windows OS if anyone claims it can does not know how operating system works and does not understand how dual booting works.

~~You have no idea what you're talking about.~~
As a rule, a Linux OS won't directly write changes to a Windows OS without user intervention.

The "Linux Time vs Windows Time" issue has been well documented for many years.
I have personally experienced it for at least 8 years (especially when using Live Linux CD/DVD/USB).

I've recently had to perform the hacks that MSClin posted on my installed operating systems.

FreeBooter · 31 Dec 2017

lehnerus2000 said:

You have no idea what you're talking about.

The "Linux Time vs Windows Time" issue has been well documented for many years.
I have personally experienced it for at least 8 years (especially when using Live Linux CD/DVD/USB).

I've recently had to perform the hacks that MSClin posted on my installed operating systems.

Wow so you are saying Linux can configure offline settings of Windows OS i think you have no idea what we are talking about because we have now established Linux time settings could configures RTC not the Windows OS time settings.

BuckSkin · 01 Jan 2018

ethel said:

Hi Buckskin, This previous post may help you to read

MSClin said:

That's because Linux use UTC time and Windows use "Local". The solution would be to make Windows use UTC time or to make Linux use Local time. I prefer to make Linux use Local, because it's just easier.

Megahertz07 said:

So when you run Linux it will set the hardware clock (RTC) to UTC time and make a correction due to the time zone to show the local time clock.
When you run windows it will load the hardware clock (RTC) that has been set to UTC by Linux. It will show GMT or UTC time until Windows makes the change to local time.

I have just made the MSClin suggestion (post #6) adding utc=no in /etc/default/rcS and it made the magic.

Thanks, everyone; I will make a stab at this.

I have never yet messed with the Linux version of Command Line; I am assuming that is where I enter this text, or am I misunderstanding ?

Thanks and have a Happy New Year !

MSClin · 01 Jan 2018

BuckSkin said:

I have never yet messed with the Linux version of Command Line; I am assuming that is where I enter this text, or am I misunderstanding ?
!

You talk about "UTC=no"? If so, I'll just give you a simple command to make Linux use Local time. Open Terminal (that's how command line is called in Linux) and enter this command:

timedatectl set-local-rtc 1

FreeBooter said:

Wow so you are saying Linux can configure offline settings of Windows OS i think you have no idea what we are talking about because we have now established Linux time settings could configures RTC not the Windows OS time settings.

I even quoted the cause of this problem, yet you still refuse to understand. "If you have multiple operating systems installed in the same machine, they will all derive the current time from the same hardware clock". And by this you should understand that if the hardware clock was set for example to UTC time, if Windows try to read it (as Windows uses Local time standard), the time would be displayed wrong in Windows. That's why every OS should use the same standard to read the hardware clock.

And the things you say doesn't make any sense. Nobody said that "Linux can configure offline settings of Windows", we basically said that if hardware clock is read with different standards, the time would be displayed wrong. All we said in this thread is documented here > Time - ArchWiki.

FreeBooter · 01 Jan 2018

MSClin said:

That's because Linux use UTC time and Windows use "Local". The solution would be to make Windows use UTC time or to make Linux use Local time. I prefer to make Linux use Local, because it's just easier.

Linux:
1. Edit "UTC=yes" to "UTC=no" in /etc/default/rcS.

Windows:
But if for some reason you want Windows to use UTC... Open Notepad and paste this code:

Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\TimeZoneInformation]
"RealTimeIsUniversal"=dword:00000001

Then save the file as "WindowsTimeToUTC.reg" and double-click to merge it with the registry. But this is not everything, you should open CMD and disable Windows Time service with this command:

sc config w32time start= disabled

Now you're finished with Windows.

Hi MSClin,

As you can see you have not mentioned about Linux modifying RTC chip setting.

MSClin · 01 Jan 2018

FreeBooter said:

Hi MSClin,

As you can see you have not mentioned about Linux modifying RTC chip setting.

Do I have to? I like to provide fast help to the people who have problems, not give them information which they can get by using Google.

FreeBooter · 01 Jan 2018

Well you should so those helping and OP can learn from you.