First post here, if this place isn’t for tech support, I’ll remove it.

I’ve heard dual booting Linux and Windows isn’t a good idea because Windows Update will nuke the Linux boot loader, so I’ve avoided doing that.

For a very long, technical, and complicated reason, I still need Windows because one piece of software that I absolutely MUST have is only compatible with Windows. No, there is no alternative software available for my use case; none, zero, not any, at all. I’ve already tried running it within many different VMs, using many different hypervisors, and I’ve already tried Wine; they aren’t an option, the software isn’t stable in those cases. I don’t want to get in the weeds about it, so please just accept that I NEED some version of Windows installed.

Since Windows 10 doesn’t receive updates anymore, can I dual boot Linux and Windows 10 without worrying about whether Windows Update will break anything?

I intend to keep Windows on one drive and Linux on another. Windows would only be used when I need to run this one specific program, which is maybe five or ten hours per week. The rest of the time, I’d be using Linux.

  • jrgd@lemmy.zipEnglish
    1·
    15 hours ago

    You can absolutely swap the primary boot entry in the BIOS by hand, but as mentioned, GRUB can be made to show an entry for Windows 10 upon normal boot. You can select that entry rather than swap the primary target in the BIOS, which will be a time saver when switching OS. Some configuration to get GRUB to pick it up will likely need to be done however.

    For that to work, one needs to uncomment a line in /etc/default/grub (#GRUB_DISABLE_OS_PROBER=false becomes GRUB_DISABLE_OS_PROBER=false). If the line simply isn’t present in /etc/default/grub, just add it at the bottom.

    For GPT, EFI installations

    On modern (EFI, GPT) systems, there is specifically one partition you will need to persistently mount from the Windows drive through fstab, being the Windows EFI partition. It does not matter particularly where it is mounted, as long as it is out of the way (a mount point like /windows is fine). You’ll have to create an empty directory preferably somewhere under / and owned by root, and then add the Windows EFI partition as a line to /etc/fstab. The command line utilities lsblk and blkid can help to determine the disk partition layout and the EFI partition’s UUID. The ‘Disks’ utility installed by default in Mint can also do this, and may be easier.

    Before touching your /etc/fstab file, make a copy of it. The resulting line added to /etc/fstab will look roughly like UUID=ABCD-1234 /windows vfat umask=0077,nofail 0 2, replacing the ABCD-1234 with the actual UUID and /windows with the actual desired mount point, if different. Running mount -a with sudo is highly recommended after touching the fstab file to verify that everything is correct. The command should complete with no errors. If it errors, revert your /etc/fstab to the copied version. Rebooting with a broken fstab file can leave your system unbootable.

    Finally, for systems like Linux Mint, run update-grub with sudo to rebuild the bootloader entries. With os-prober enabled in /etc/default/gruband the Windows EFI partition mounted if relevant, update-grub should show a warning about os-prober being enabled and among other entries, an entry for Windows 10 should be present. As long as the Windows drive continues to be installed in the system, a boot entry should be available next to your Linux Mint and bios entry options in GRUB going forward.