Arch Linux

py

Member

Registered: 2025-01-09

Posts: 7

Multiple Boot Systems Time Conflicts ( Windows )

Hello guys. Thanks for caring for my problem.

Problem

When many OS use UTC as harware clock(RTC), Windows choose localtime for RTC, which cause time conflicts.

The following is a link calling on Microsoft to use UTC:

A plea to the developers in charge of the real-time clock driver in Microsoft operating systems.

--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Workaround I have discovered & Why not use them

According to Arch wiki UTC_in_Microsoft_Windows & Time_standard

    1. Set both Arch Linux and Windows to use UTC

    Seems good enough. But see RealTimeIsUniversal, let Windows
    assume RTC time as UTC time not support well.

   2. Set Arch Linux to localtime and disable all time synchronization daemons.

    This method may cause issues as well, though ubuntu community wiki suggests this way when dual boot.   
   

Otherwise, if the hardware clock is set to localtime, more than one operating system may adjust it after a DST change for example, thus resulting in an over-correction; problems may also arise when traveling between different time zones and using one of the operating systems to reset the system/hardware clock.

   

https://help.ubuntu.com/community/Ubunt … _Conflicts

Changing Linux to use local time is easier and more reliable than changing Windows to use UTC, so dual-boot Linux/Windows systems tend to use local time.

    3. Set Windows to use UTC (no changing registry)
    I have no idea whether it work or not

   

https://superuser.com/questions/884278/ … -and-linux

You could also set the Windows side to use UTC as a time zone and turn off automatic daylight saving time changes in Windows, and keep Linux set to have the RTC in UTC and display the time converted according to its practices.

---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

So can I use method 3 above as the best solution (I'm unwilling to change windows registry) ? Or is there other way you are using?

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 24,094

Re: Multiple Boot Systems Time Conflicts ( Windows )

RealTimeUniversal is absolutely unproblematic here since years. And the wiki you digged up from god knows where that reccommends against it cites a microsoft source that only applies to Windows 8 and earlier. Most of the concerns here are fixed in Windows 10+

cryptearth

Member

Registered: 2024-02-03

Posts: 1,329

Re: Multiple Boot Systems Time Conflicts ( Windows )

the proper solution is to set both to use RTC as UTC - no local time
the cited link refers to something win7/8 from 10 years ago
microsoft learned and fixed a lot since - and it breaks way less stuff to have windows offset by have it wrong see utc as local - which will be -14/+12 at most - instead of setting linux to local time