Create Dual Boot with Win10 FROM UBUNTU

[tux-peng]

I prefer separate drives as well; but if you use the same drive, maybe you should install grub to the root partition and use easybcd from within windows to chainload grub

[THEKINGDOM]

i know it costs more, but separate computers is the ultimate for having Linux and Windows together. I've done this before and even had the two computers right next to each other and connected them to the same LAN. they seemed to get along OK and neither did any damage or file corruption to the other. you might not be able to do this right away, but planning it for the future might let you do it. i know Ubuntu likes it when it doesn't have to reboot until the next kernel upgrade.

Why not just separate drives, rather than separate computers?

[THEKINGDOM]

I prefer separate drives as well; but if you use the same drive, maybe you should install grub to the root partition and use easybcd from within windows to chainload grub

I've just picked up an Intel SSD 660P-Series, 512GB for the Windows OS reside.

[THEKINGDOM]

You might take a look at the Ubuntu documentation on dual booting with windows 10 at the site at the link below. If you do windows EFI you should install Ubuntu EFI also or it will make the boot process more convoluted. One problems with EFI is that Ubuntu will install Grub efi files to the first EFI partition it finds which could be the windows drive.

https://help.ubuntu.com/community/UEFI

hmm okay.
I've got the drive and the ISO for Win10. Ready to rock and roll.

We didn't quite establish how I can create a dual boot to WIn10 from a current Ubuntu OS.
Can I just load the WIn10.ISO to the new drive and then have window 10 install to that drive itself? If so, How would UEFI recognize the ISO?

Help is greatly appreciated

[yancek]

We didn't quite establish how I can create a dual boot to WIn10 from a current Ubuntu OS.

You can't boot and install windows from Ubuntu or any Linux system but you can create a bootable windows usb or DVD. The link below gives a very detailed explanation of this using Ubuntu. I'd read through the page before beginning following the steps and pay particular attention to the GPT/UEFI sections. If you have Ubuntu UEFI, then you need windows UEFI. If Ubuntu is Legacy/CSM, then windows needs to be the same. If the drive you will use for windows is GPT, you must install windows UEFI.

http://onetransistor.blogspot.ch/201...om-ubuntu.html


If you use the UEFI method, you should see an option on booting the computer in the BIOS/firmwate to select the usb drive with the 'UEFI' in the option.

[oldfred]

I do not know about UEFI install of Windows, but with BIOS version you have to be careful on drives.

And be sure to have good backups before any major system change.

Windows will install its boot loader to drive seen as default boot in BIOS.
Some install Windows to sdb drive and it has a small boot partition on sda. Users have deleted that boot partition and broken Windows.
Have also seen cases where Windows install just arbitrarily put boot partition on sda, overwriting the start of a Linux partition damaging Ubuntu.

If newer system better to use UEFI, but as yancek says you want both Ubuntu & Windows in same boot mode, both UEFI or both BIOS.

Whether UEFI or BIOS, better to disconnect, either physically or with settings in UEFI to make inactive, so Windows installer only sees new drive.
You may lose UEFI entry for Ubuntu, but can easily recreate with Boot-Repair or efibootmgr. Many systems lose UEFI entries when drive is removed.
And if Windows fast start up is off, you can in Ubuntu run this to chainload in grub to boot Windows.
sudo update-grub

[yancek]

Windows 10 has a "Custom" installation option which you should see just after the page with the EULA. I used this on a Legacy machine to install windows 10 to an already existing ntfs partition and the only problem was that windows overwrote the boot code in the MBR. That was an easy fix. I'm not sure what happens with an EFI system but I would expect you would be able to do something similar as windows creates separate directories for its EFI files on the EFI partition. That's just a guess as I have not done it myself.

[THEKINGDOM]

Attached boot repair log:
http://paste.ubuntu.com/p/9WjWk2smF5/

Not quite sure if I'm on UEFI or not on the boot drive - /dev/nvme0n1p4
Want to be on UEFI before I attempt to install Win10 OS to a separate M.2-SSD

FYI in the above log - sda & sdb are my ZFS data RAID - shouldn't be anything to do with boot.
I've just moved over from AMD back to Intel today. It seems as if the dredded GRUB screen is now appearing again on every boot and I'm not sure why. Is there any issue with having non-boot drives in SATA slots 1 & 2?

Any help is greatly appreciated

[yancek]

Not quite sure if I'm on UEFI or not on the boot drive - /dev/nvme0n1p4

That would be the system partition on which you have your Ubuntu install. Take a look at the boot repair file, line 110 shows:

/dev/nvme0n1p1 308D-E09D vfat

The vfat would indicate your EFI partition. Look at line 211 which clearly shows an EFI partition.

/dev/nvme0n1p1: UUID="308D-E09D" TYPE="vfat" PARTLABEL="EFI System Partition" PARTUUID="ec4290d6-24a0-4b3f-924f-c4605c52ca57"

Since the disk on which you have Ubuntu and want to also install windows is GPT (see line 703 of boot repair), that means you must install windows UEFI. Also, on line 707, your EFI partition is shown and on line 708 it shows BIOS boot partition. You do not need this as the BIOS boot partition is used only for a non-UEFI install on a GPT partition with Linux. You might want to disable Legacy/CSM boot in the BIOS firmware before installing. Line 709 shows you have a swap partition and newer versions of Ubuntu do not use/need a swap partition but rather a swap file so this is also probably not needed but should not hurt anything, other than using up space. 32GB is much more than necessary. If you add up the space used for the partitions on the SSD, they come out to approximately the full size of the drive so there is no place on which to install windows. You need an ntfs partition for windows and 30GB is probably the bare minimum necessary.

Just read over your previous posts. Have you got a 2nd drive for windows? That would eliminate the size problem on the above drive. If you do have another drive, after burning your windows iso to a DVD or putting it on a USB, it would probably simplify things if you were able to dis-connect the Ubuntu SSD so it is not overwritten. That would lead to another possible problem with multiple EFI partitions, one on the Ubuntu drive and one on the windows. That should not be that difficult to resolve.

I'd suggest again, reading through the Ubuntu documentation on dual booting with windows 10 UEFI.

[oldfred]

While you have the ESP, if you also have a bios_grub you must have installed in both modes or converted install.
Boot-Repair seems to want to reinstall grub in BIOS boot mode.
Report also did not show /etc/fstab which would show if ESP is mounted or not. Reinstall of grub in BIOS mode would comment it out with #.

Saw a post where user was having issue and it related to the ZFS being set as back up boot in UEFI settings causing issues.
Post by THEKINGDOM
https://ubuntuforums.org/showthread....0#post13904610

Post this, since missing from report:
cat /etc/fstab