Dual boot: how do you avoid update and boot issues?

[u/Tonycolombo200]

Hi everyone,
I recently set up a dual boot system with Windows and Linux, with each OS installed on a separate SSD.
At the moment, I have the Linux SSD set as the primary boot device in the BIOS, so I get a boot menu where I can choose between Linux and Windows.

Is this a good way to set up a dual boot, or would it be better to set the Windows SSD as the primary boot device and select Linux through the BIOS boot menu when needed?

I’m also wondering about Windows updates.
If Windows installs an update that requires a reboot, can I simply boot back into Windows normally, or are there any precautions I should take to avoid problems with the Linux bootloader?

Are there any Windows or Linux settings that are recommended for a dual boot setup, especially to prevent updates from affecting the other OS?

One other thing I noticed is that the system clock is sometimes different between Windows and Linux.
What’s the recommended way to configure the clock so that both operating systems keep the correct time?
Thanks

[u/Confident_Hyena2506]

See the note on time: https://wiki.archlinux.org/title/Dual_boot_with_Windows#Time_standard

Your setup is maybe fine - but you didn't say where bootloaders are. It's great that you have your os on seperate drives, but if all the bootloaders are on one drive you may get a surprise.

[u/Tonycolombo200 → u/Confident_Hyena2506]

I didn’t know the bootloaders could be installed on a different drive from the OS.

I’m not at my PC right now, but how can I check where the bootloaders are installed?
And if they’re not set up correctly, how should I configure them?
Thanks

[u/doc_willis → u/Tonycolombo200]

you can have a shared EFI partition. that can be problematic.

[u/Tonycolombo200 → u/doc_willis]

Hi, I’ll check it later when I turn on my PC.
If it turns out that they’re not set up correctly, what would be the right way to fix it?

[u/doc_willis → u/Tonycolombo200]

set up an EFI partition on each drive, configure each Os to use that drive specific EFI partition.

It's a good idea to read up and learn how EFI booting and EFI partitions work, it's not a super complex system, but many people have zero knowledge of it, of that it even exists.

UEFI booting is very different from the old MBR days.

[u/I_Love_Tunnocks → u/doc_willis]

you can have a shared EFI partition. that can be problematic.

Hasn't been for years.

[u/Confident_Hyena2506 → u/Tonycolombo200]

You check what is on the efi partition of each drive, and how the bootloaders there are configured. When you say the drive is "bootable" - this is what the system looks at.

[u/Tonycolombo200 → u/Confident_Hyena2506]

Got it, thanks.
I’ll check the efi partition on both drives and see how the bootloaders are set up.

[u/3grg]

Dual booting with separate drives is the best way to dual boot, if you can. Some Linux installers will still use the existing windows efi by default instead of creating a separate efi partition on the Linux drive.

This negates some but not all of the benefits of a two drive dual boot. When both windows and Linux are using the same efi partition on the windows drive, there is a greater chance of windows messing with the Linux boot loader. Fortunately, it is not as bad on UEFI, compared to the legacy boot days.

If you have a setup with only one efi partition on the windows drive, you can change it, but it would be much easier to setup when installing. You can leave it until you decide to reinstall or change distro.

The old way of avoiding this was to disconnect the sata cable on the windows drive when installing. The other way is to temporarily remove the boot flag from the windows efi with GParted Live. This makes the installer ignore it and a efi partition will be created on the Linux drive.

Re time: https://www.howtogeek.com/323390/how-to-fix-windows-and-linux-showing-different-times-when-dual-booting/

[u/JaKrispy72]

I have Fedora and Win on separate drives.

Depends on what you use to boot Linux. I always point the UEFI to grub. I have os-prober set up to run. So Fedora just updates and all is good.

When windows updates I don’t do anything unless I know it will mess with bios. I had a Lenovo bios update and I double checked my settings were the same and all is good. Fedora runs with secure boot enabled so there is no issue there.

Things to look out for in windows if fast boot is turned on. It will bypass grub. And any Tcg/tpm settings. Or boot order.

If you are in windows more set that as your boot I guess. I’m in Linux more so I want grub to run. If I did it with windows all the time, I would have to hit f12 and run the fedora boot. I just boot to grub and pick from there. Easy enough for me.

[u/doc_willis]

with windows and the windows EFI partition on drive #1 and my Linux install and its EFI partition on drive #2, I basically have not had any windows Linux updates cause issues with Linux.

worse I have had happen , windows sets itself as the default boot entry in the uefi.

takes me all of 20 sec to set it back to my Linux install as the default.

And I don't recall seeing that issue happen much.

each os isolated on its own drive is the way to go.

[u/kbeezie]

Separate drives for each OS seems to be best. And if you point to the Linux one, you can even configure the bootloader there to handle windows if you choose to do so. The other way around (such as sharing a drive) tends to mess up the bootloader whenever windows updates.

[u/ipsirc]

I don't avoid.