Re: (solved) Re: Dual boot: one legacy, the other uefi
Hello guys, As I promised, here a more detailed solution, with the steps I really used: The problem: * You have a Windows 10 UEFI and a Linux Legacy boot. They both work, but to choose what to boot you need to change the BIOS option each time. Possible solutions discussed in the thread: 1. Let it be. Don't try to fix what ain't broke. 2. Try to make grub legacy find and boot windows 3. Move Linux boot to UEFI as well. Solution I chose was 3: lets move Linux Legacy to Linux UEFI under these conditions. Step-by-step solution to "MY" case. Be careful as your system might have small differences that would make a huge difference in the end. Special attention to /dev/sdXN partition names and the respective UUID used in FSTAB. First step: with a UEFI setup on BIOS, bring up the Linux Legacy. To do this, you need to boot from a USB stick, as your Linux won't boot. Then you need to give control to the Linux on the harddrive (chroot). The steps are: # boot do debian live of your choice, preferred the same version you have on HD. You will need the internet. Check if apt-get is working on your live system. Maybe install some innocuous/small package like "ascii" Create a point for the new root (in my example it is in sda8): # mkdir /mnt/root # mount -t ext4 /dev/sda8 /mnt/root Now we need to setup the EFI boot # mkdir /mnt/rooot/boot/efi Find your current UEFI partition (maybe fdisk -l will help you), then mount it: # mount /dev/sda1 /mnt/rooot/boot/efi Now prep to change root. Mount all essencial filesystems: # mount --bind /sys /mnt/rooot/sys/ # mount --bind /proc /mnt/rooot/proc/ # mount --bind /dev /mnt/rooot/dev/ # mount --bind /dev/pts /mnt/rooot/dev/pts/ # mount --bind /run /mnt/rooot/run/ Be sure the internet will work after chroot with: # cp /etc/resolv.conf /mnt/root/etc/resolv.conf Find the correct UUID of the UEFI partition. You will need this information to add to fstab file. (Use commands like blkid or fdisk -l -o +UUID or ls /dev/disk/by-uuid) Add it to your FSTAB echo "UUID=A2YOUR14-9UUID22 /boot/efi vfat defaults0 2" >> /mnt/rooot/etc/fstab Now finally, do the magic: chroot /mnt/root You should now "be" on the main Linux on your HD. Test apt-get to be sure with some small/useless package. You really don't want to mess up the following commands! # apt-get install figlet This is the "almost" irreversible part. Until now you were playing with kid's commands. Remove the old legacy grub. Add the new UEFI grub Re-install the grub menu and hopefully it will recognize your windows. # apt-get remove grub-pc # apt-get install grub-efi # grub-install /dev/sda Check if this file exists, to be sure you are on a UEFI partition now: # file /boot/efi/EFI/debian/grubx64.efi Chek also the output of this command and find DEBIAN there: # efibootmgr Go back to your old root # exit Remove your USB-stick and... # reboot Check this website for some other insights: https://blog.getreu.net/projects/legacy-to-uefi-boot/ On my machine I needed also to remove this options in the BIOS: BIOS - removed secure boot That is all. Have a good hacking. My best, Dr. Béco PS. These instructions come WITHOUT ANY WARRANTY. Always have your backup ready to reinstall everything. On Thu, 10 Oct 2019 at 18:15, Beco wrote: > > Hello all, > > Thank you very much for all this thread and discussion. > > Let me get back to you. > > On Sun, 6 Oct 2019 at 18:26, Pascal Hambourg > wrote: > > > Dear Pascal, > > > >> >> If Windows boots in EFI mode : >> Mount the EFI partition on /boot/efi. >> Install grub-efi-amd64. >> Boot some Linux media in EFI mode. >> Chroot into the Debian system, mount the usual pseudo-filesystems >> (/proc, /dev...) and the EFI partition. >> Run grub-install. >> Run update-grub. >> Done. >> >> >> > > Your simplified solution nailed it! Thank you. > > I mark this thread as solved basically because of this small paragraph. So > if you are reading this in the near future trying to find a solution, this > step-by-step and some duckduckgo will get you into business. > > > There are more details for a complete response, and some commands needs to > be in a different order, that I'll reply later in this thread, just to make > sure the procedure that I made and worked flawlessly, is registered for > posterity. > > For now, if you are in a hurry, this answer above will get you in the > right path. > > My best, > > Beco > > > > -- > Dr Beco > A.I. researcher > > "I know you think you understand what you thought I said but I'm not sure > you realize that what you heard is not what I meant" -- Alan Greenspan > > GPG Key: > https://pgp.mit.edu/pks/lookup?op=vindex=0x5A107A425102382A > Creation date: pgp.mit.edu ID as of 2014-11-09 > -- Dr Beco A.I. researcher "I know you think you understand what you thought I said but I'm not sure you realize that what you heard is not what I meant" -- Alan Greenspan GPG Key: https://pgp.mit.edu/pks/lookup?op=vindex=0x5A107A425102382A Creation
(solved) Re: Dual boot: one legacy, the other uefi
Hello all, Thank you very much for all this thread and discussion. Let me get back to you. On Sun, 6 Oct 2019 at 18:26, Pascal Hambourg wrote: Dear Pascal, > > If Windows boots in EFI mode : > Mount the EFI partition on /boot/efi. > Install grub-efi-amd64. > Boot some Linux media in EFI mode. > Chroot into the Debian system, mount the usual pseudo-filesystems > (/proc, /dev...) and the EFI partition. > Run grub-install. > Run update-grub. > Done. > > > Your simplified solution nailed it! Thank you. I mark this thread as solved basically because of this small paragraph. So if you are reading this in the near future trying to find a solution, this step-by-step and some duckduckgo will get you into business. There are more details for a complete response, and some commands needs to be in a different order, that I'll reply later in this thread, just to make sure the procedure that I made and worked flawlessly, is registered for posterity. For now, if you are in a hurry, this answer above will get you in the right path. My best, Beco -- Dr Beco A.I. researcher "I know you think you understand what you thought I said but I'm not sure you realize that what you heard is not what I meant" -- Alan Greenspan GPG Key: https://pgp.mit.edu/pks/lookup?op=vindex=0x5A107A425102382A Creation date: pgp.mit.edu ID as of 2014-11-09
Re: Dual boot: one legacy, the other uefi
On 2019-10-08, Joe wrote: > > But I'm pretty sure that any pre-installed Windows, and very few people > now install it themselves, will be a UEFI installation, which cannot be > changed to boot in legacy mode, nor vice-versa. > >From what I'm understanding you're batting a thousand here, Joe. https://docs.microsoft.com/en-us/windows/deployment/mbr-to-gpt https://www.asus.com/us/support/FAQ/1013017/ -- "There are no foreign lands. It is the traveler only who is foreign." -- Robert Louis Stevenson
Re: Dual boot: one legacy, the other uefi
On Mon, 7 Oct 2019 23:29:09 +0200 Pascal Hambourg wrote: > Le 07/10/2019 à 09:42, Joe a écrit : > > On Sun, 6 Oct 2019 23:26:32 +0200 > > Pascal Hambourg wrote: > > > >> Le 06/10/2019 à 22:45, Beco a écrit : > >>> > >>> Now the system can boot both systems ok. But to choose which one > >>> you want, you need to enter the BIOS, change legacy to UEFI, and > >>> vice-versa, then you can boot. > >> > >> Would you mind telling which systems boots in EFI mode and which > >> one boots in legacy mode ? > >> > > Windows 8/8a/10 boot only in EFI. > > I don't think so. Source ? > As I Understood It. Definitely, computers certified for these versions must have EFI mode available, which is not, of course, the same thing. Yes, even Win10 appears to be able to be installed to boot in legacy mode. Shows how many Windows installations I've done recently But I'm pretty sure that any pre-installed Windows, and very few people now install it themselves, will be a UEFI installation, which cannot be changed to boot in legacy mode, nor vice-versa. -- Joe
Re: Dual boot: one legacy, the other uefi
Le 07/10/2019 à 09:42, Joe a écrit : On Sun, 6 Oct 2019 23:26:32 +0200 Pascal Hambourg wrote: Le 06/10/2019 à 22:45, Beco a écrit : Now the system can boot both systems ok. But to choose which one you want, you need to enter the BIOS, change legacy to UEFI, and vice-versa, then you can boot. Would you mind telling which systems boots in EFI mode and which one boots in legacy mode ? Windows 8/8a/10 boot only in EFI. I don't think so. Source ?
Re: Dual boot: one legacy, the other uefi
On Sun, 6 Oct 2019 17:45:37 -0300 Beco wrote: > Hi guys, > > I have this laptop problem to solve: the original windows 10 is kept, > shrunk partition to 1TB, originally cryptographied (but now normal). > The rest was given to Linux, Debian 10: 800GB root and 8.2GB swap. > > Now the system can boot both systems ok. But to choose which one you > want, you need to enter the BIOS, change legacy to UEFI, and > vice-versa, then you can boot. > > Not a good way to keep. When I needed windows I had once succes with rEFInd boot manager, apt install refind Always have a rescue USB stick at hand though, windows 10 has nasty suprises. Wish you good luck.
Re: Dual boot: one legacy, the other uefi
On Sun, 6 Oct 2019 23:26:32 +0200 Pascal Hambourg wrote: > Le 06/10/2019 à 22:45, Beco a écrit : > > > > Now the system can boot both systems ok. But to choose which one > > you want, you need to enter the BIOS, change legacy to UEFI, and > > vice-versa, then you can boot. > > Would you mind telling which systems boots in EFI mode and which one > boots in legacy mode ? > Windows 8/8a/10 boot only in EFI. -- Joe
Re: Dual boot: one legacy, the other uefi
Le 06/10/2019 à 22:45, Beco a écrit : Now the system can boot both systems ok. But to choose which one you want, you need to enter the BIOS, change legacy to UEFI, and vice-versa, then you can boot. Would you mind telling which systems boots in EFI mode and which one boots in legacy mode ? Not a good way to keep. Some people think otherwise. It is not the most convenient, but it prevents Windows to interfere with GRUB's operation. Lets give the devices some names. /dev/sda4 is windows 10 /dev/sda5 is debian buster 10 /dev/sda6 is swap Grub is installed at sda5 with Debian, but when updated it doesn't recognize A Windows partition. Of course not. Both systems must be set up to boot in the same mode. Can you point me to a possible howto, blog, set of instructions or even abstract ideas that are in the right direction? If Windows boots in EFI mode : Mount the EFI partition on /boot/efi. Install grub-efi-amd64. Boot some Linux media in EFI mode. Chroot into the Debian system, mount the usual pseudo-filesystems (/proc, /dev...) and the EFI partition. Run grub-install. Run update-grub. Done. If Windows boots in legacy mode : Create a partition with "BIOS boot" type. 100 ko is more than enough. Install grub-pc. Done.
Re: Dual boot: one legacy, the other uefi
On Sun, 6 Oct 2019 17:45:37 -0300 Beco wrote: > Hi guys, > > I have this laptop problem to solve: the original windows 10 is kept, > shrunk partition to 1TB, originally cryptographied (but now normal). > The rest was given to Linux, Debian 10: 800GB root and 8.2GB swap. > > Now the system can boot both systems ok. But to choose which one you > want, you need to enter the BIOS, change legacy to UEFI, and > vice-versa, then you can boot. > > Not a good way to keep. > > Lets give the devices some names. > > /dev/sda4 is windows 10 > /dev/sda5 is debian buster 10 > /dev/sda6 is swap > > Other partitions are the usual that comes with a Windows Dell laptop > (boot, backup, etc.) > > Grub is installed at sda5 with Debian, but when updated it doesn't > recognize A Windows partition. > > Can you point me to a possible howto, blog, set of instructions or > even abstract ideas that are in the right direction? > Installation notes for Debian 10, on the Debian website. I installed stretch (stable at the time) on a Win10 netbook without problems. There is no legacy BIOS in that machine, so Debian had to be installed UEFI and it Just Worked. The grub menu lists the Windows boot manager underneath the Debian entry. There will be a UEFI partition apart from those you named, Windows requires it and Debian can use it. Certainly stretch was UEFI-enabled, so I assume buster is also. -- Joe
Dual boot: one legacy, the other uefi
Hi guys, I have this laptop problem to solve: the original windows 10 is kept, shrunk partition to 1TB, originally cryptographied (but now normal). The rest was given to Linux, Debian 10: 800GB root and 8.2GB swap. Now the system can boot both systems ok. But to choose which one you want, you need to enter the BIOS, change legacy to UEFI, and vice-versa, then you can boot. Not a good way to keep. Lets give the devices some names. /dev/sda4 is windows 10 /dev/sda5 is debian buster 10 /dev/sda6 is swap Other partitions are the usual that comes with a Windows Dell laptop (boot, backup, etc.) Grub is installed at sda5 with Debian, but when updated it doesn't recognize A Windows partition. Can you point me to a possible howto, blog, set of instructions or even abstract ideas that are in the right direction? My best, -- Dr Beco A.I. researcher "I know you think you understand what you thought I said but I'm not sure you realize that what you heard is not what I meant" -- Alan Greenspan GPG Key: https://pgp.mit.edu/pks/lookup?op=vindex=0x5A107A425102382A Creation date: pgp.mit.edu ID as of 2014-11-09
