There are some things about clock that as a simple user I cannot understand:

1) In a dual boot Windows(10)+Linux(Slack15) installation, setting the Linux clock on "local" should align it with the Windows way to manage clock, so one wouldn't expect any malfunctioning.
2) While using Linux, Windows is turned off and anyway never can't access to Linux, so it shouldn't interfere at all.
3) Instead, the clock jumps 1 hour onward every some minutes.

It's fanny that I had the same problem a couple of decades ago with a Win2000 + RedHat8 installation. More than twenty years later I'm encountering the same problem.

Most of the time I use my PC or laptop working offline with Win or Linux, I don't need to be connected to any network.

The best solution I've adopted until now is to comment the hwclock entries out in rc.0 and rc.6.

If someone could suggest a solution better than that, intervening on Linux only, it would be very appreciated.

https://www.howtogeek.com/323390/how...-dual-booting/

I recommend option two: Running Windows on "Universal" time.

Set slackware to use universal time (if it does not already) using the timeconfig dialog, then reboot into windows and follow the above guide. Once done, set the correct time and when you reboot into slackware again the time should be correct, and should stay correct (barring any systematic drift in your hardware clock).

There is the option of running linux on localtime like windows does, but if you do that then twice a year you're going to have to intervene manually to make the DST changes go smoothly. Always ensuring you start Windows before linux after a DST change occurs in order to let it adjust the local clock is one way to handle it, but you have to remember to do it each time. It's not ideal, but if you're not prepared to make any changes to Windows, then this is your best bet.

Note: PC hardware clocks tend to drift much more compared to a reference time than the linux system clock does, so commenting out the hwclock --systohc on shutdown isn't the best idea from a clock accuracy standpoint.

1 members found this post helpful.

Many thanks for your reply.

I'd rather not to modify the Windows settings.

I'm likely to keep the Windows time back to get the right time in Linux.

I understand.

If you leave timeconfig set to using localtime and avoid using ntp on linux you should be fine as long as you take extra care on the days that the DST adjustments happen.

Fine, I'll take on the fatigue to fix time according to DST. Not a big effort, after all. Thanks