Re: install Kernel and GRUB in chroot.
On 05/02/2024 17:40, Dmitry wrote: > It would not work with secure boot Yes. But secure boot is usually turned off. It is a standard advice during Linux installation. That advice may be standard for distributions that do not provide signed shim and grub. Likely it is applicable for Arch and derivatives. Debian supports installation with enabled secure boot. At first I suspected that you enrolled your own MOK and maybe even wiped out Microsoft keys. Perhaps you may get encrypted /boot in Debian similar to what you have in Manjaro, but certainly it is not default configuration.
Re: install Kernel and GRUB in chroot.
On Mon, 2024-02-05 at 17:40 +0700, Dmitry wrote: > > But secure boot is usually turned off. It is a standard advice during > Linux > installation. > Will probably be increasingly common though, I've got a Microsoft Surface Laptop that works fine with Debian, but if you switch off secure boot, it displays some big red scary warning screen before the bootloader. /ralph
Re: install Kernel and GRUB in chroot.
> It would not work with secure boot Yes. But secure boot is usually turned off. It is a standard advice during Linux installation.
Re: install Kernel and GRUB in chroot.
sudo -i Thank you! I am unsure what UUID you mean. At Manjaro: grubx64.efi is at the sdb1 - EFI vfat /dev/sdb1 grub.cfg is at the sdb2 - crypto_LUKS /dev/sdb2 grubx64.efi contains data UUID=""a8...b7" of /dev/sdb2 which is TYPE="crypto_LUKS". `blkid` output: /dev/sdb2: UUID="a8...b7" TYPE="crypto_LUKS" PARTUUID="8...5" `strings /boot/efi/EFI/Manjaro/grub64x.efi` output: cryptomount -u a8...b7 (cryptouuid/a8...b7)/boot/grub I have a Manjaro installed, and what to migrate to Debian. That involves exploration of Booting order. In the Manjaro GRUB installation mounting point for ESP (sdb1) is: /boot/efi And the grub.cfg is /boot/grub/grub.cfg The grub.cfg located at the crypto partition sdb2. Manjaro has different GRUB installation scheme from Debian.
Re: install Kernel and GRUB in chroot.
On 03/02/2024 22:32, Dmitry wrote: 2. sudo bash sudo -i 3. cd /boot/efi/EFI/Mangaro 4. strings grubx64.efi 5. And at the output of strings there is UUID and /boot/grub. I am unsure what UUID you mean. Summary: GRUB installation not only involves configuration of text files, but also it involves generating data in binary grubx64.efi. It would not work with secure boot md5sum /boot/efi/EFI/debian/grubx64.efi /usr/lib/grub/x86_64-efi-signed/grubx64.efi.signed 62ff1ee5b75b4565f609043c4b1da759 /boot/efi/EFI/debian/grubx64.efi 62ff1ee5b75b4565f609043c4b1da759 /usr/lib/grub/x86_64-efi-signed/grubx64.efi.signed
Re: install Kernel and GRUB in chroot.
Tim Woodall composed on 2024-02-03 21:25 (UTC): > Max Nikulin wrote: >> It seems secure boot is disabled in your case, so I am wondering why you do >> not boot xen.efi directly. > Because the NVRAM is extremely tempremental. Not in my experience. I recognized long ago that WRT non-removable media, only one bootloader per machine is required, and pretty well stuck to having only one active, or at all, no matter how many FOSS operating systems or media I have installed. The Grubs I have used are not picky about whose kernel or initrd they are called to load. With only one bootloader installed, retouching NVRAM isn't often required, and there needn't be much in it to scramble. -- Evolution as taught in public schools is, like religion, based on faith, not based on science. Team OS/2 ** Reg. Linux User #211409 ** a11y rocks! Felix Miata
Re: install Kernel and GRUB in chroot.
On Sat, 3 Feb 2024, Max Nikulin wrote: It seems secure boot is disabled in your case, so I am wondering why you do not boot xen.efi directly. Because the NVRAM is extremely tempremental. Most updates fail, or worse, corrupt it to the point it's hard to get anything to boot. Additionally, there was a bug in an older version of xen that caused a kernel oops if wifi networking was started. So I wanted to start vanilla debian and I don't dare touch the NVRAM again (or the bios) until I absolutely have to. I don't remember for certain now but I might be booting using bootx86.efi (which is a copy of grubx64.efi) It's an old laptop but it still works well for me.
Re: install Kernel and GRUB in chroot.
Main question is resolved. GRUB knows how to reach grub.cfg because grubx64.efi binary has the UUID and path to grub configurations. 1. sudo blkid; 2. sudo bash 3. cd /boot/efi/EFI/Mangaro 4. strings grubx64.efi 5. And at the output of strings there is UUID and /boot/grub. Summary: GRUB installation not only involves configuration of text files, but also it involves generating data in binary grubx64.efi.
Re: install Kernel and GRUB in chroot.
On 03/02/2024 02:15, Tim Woodall wrote: $ cat /boot/efi/EFI/XEN/xen.cfg [...] I'd be interested if there's a way to tell grubx64.efi to look for a particular partition UUID. An example of such grub.cfg from EFI/debian has been posted already in this thread https://lists.debian.org/msgid-search/20240201200846.0bb82...@dorfdsl.de Frankly speaking, I am unsure concerning your configuration. Perhaps the following may make it more clear efibootmgr -v find /boot/efi | sort It seems secure boot is disabled in your case, so I am wondering why you do not boot xen.efi directly.
Re: install Kernel and GRUB in chroot.
On 03/02/2024 02:51, Thomas Schmitt wrote: Max Nikulin wrote: Just copy files from LiveCD (it should have EFI/Boot/bootx64.efi) to the ESP partition on the USB stick. The /EFI/boot directory of a bootable Debian ISO usually does not contain the full GRUB equipment for EFI. Important parts of an amd64 Live ISO are in /boot/grub. Certainly. And grubx64.efi in EFI/Boot of a live media behaves a bit differently from one in EFI/debian of a regular install since in the former case it relies on boot/grub residing on the same partition. My point was to copy *files* to the pre-partitioned drive, not a whole image to the whole block device. I had a hope that the topic starter is aware of the recommended way to create a bootable USB stick using dd (or cp, etc.). I usually copy files to existing single FAT partition on USB drives having msdos partition table (as they are shipped). It requires additional actions to setup syslinux for the sake of legacy boot, but it leaves enough space to put some additional files while the boot drive is prepared or during live session (requires remounting as rw). UEFI boot relies on files and their specific layouts, not on specific block addresses.
Re: install Kernel and GRUB in chroot.
On 02/02/24 at 15:12, Dmitry wrote: Going to read carefully. https://www.debian.org/releases/buster/amd64/ch04s03.en.html Interesting that Buster has more documentation than current release. Nope, maybe you gave a quick read, the release notes of the current release ¹ are exhaustive. If you need to go deeper, a link ² to the wiki it's published in that page. Kind regards, ¹ https://www.debian.org/releases/bookworm/amd64/ch04s03.en.html ² https://wiki.debian.org/DebianInstaller/CreateUSBMedia -- Franco Martelli
Re: install Kernel and GRUB in chroot.
Hi, Dmitry wrote: > Yep. `dd` copy partitions table. Amazing. Not so amazing after you realize that a partition table is just data on the storage medium and not some special property of the storage device. dd copies data. If these data contain a partition table and get copied to the right place on the storage medium, the partition table will be recognized by EFI and Linux. > applies no 'intelligence' to the operation. This describes it very well. Sometimes dumb is good. Sometimes not. Initially you stated in https://lists.debian.org/debian-user/2024/02/msg8.html >...> I need to prepare that system for booting. >...> 1. Install Kernel. >...> 2. Install GRUB and Configure. >...> 3. Add changes to UEFI to start booting. dd-ing a bootable Debian ISO will not do what you describe. Assumed the ISO is prepared for booting from USB stick, you will get a bootable Live or an installer system. At least ISOs for i386, amd64, and arm64 should be prepared for that. If it is not ready for booting from USB stick, it will be just a storage with a mountable filesystem and Debian files in it. Max Nikulin wrote: > > Just copy files from LiveCD (it should have EFI/Boot/bootx64.efi) > > to the ESP partition on the USB stick. The /EFI/boot directory of a bootable Debian ISO usually does not contain the full GRUB equipment for EFI. Important parts of an amd64 Live ISO are in /boot/grub. The programs in /EFI/boot are specialized on convincing Secure Boot and on finding the ISO filesystem with /boot/grub in it. (Actually those are copies of the EFI boot partition files. The boot partition is a FAT filesystem image file inside the ISO named /boot/grub/efi.img .) Tim Woodall wrote: > > I'm not exactly sure what you're doing. I join this statement. :)) Do you want a normal changeable Debian system installation or do you want a Live system with its immutable core and maybe some partition where you can store files ? (Just curiosity of mine. Possibly i could not help much with chroot questions anyway.) Have a nice day :) Thomas
Re: install Kernel and GRUB in chroot.
On Thu, 1 Feb 2024, Marco Moock wrote:
Am 01.02.2024 um 19:20:01 Uhr schrieb Tim Woodall:
$ cat /boot/efi/EFI/XEN/xen.cfg
[global]
default=debian
[debian]
options=console=vga smt=true
kernel=vmlinuz root=/dev/mapper/vg--dirac-root ro quiet
ramdisk=initrd.img
menuentry "Xen EFI NVME" {
insmod part_gpt
insmod search_fs_uuid
insmod chain
#set root=(hd1,gpt1)
search --no-floppy --fs-uuid --set=root C057-BC13
chainloader (hd1,gpt1)/EFI/XEN/xen.efi
}
Then this file tells the boot loader about the /boot or / partition.
Is that the Xen virtualization software?
The NVRAM is configured to boot:
/boot/efi/EFI/debian/grubx64.efi
That then hunts for grub.cfg. I believe it finds the first grub.cfg -
which has caused me issues in the past where I've had a legacy partition
on the disk that I'd forgotten about but the efi application sees. I'd
be interested if there's a way to tell grubx64.efi to look for a
particular partition UUID.
That menuentry above then tells efi to chainload the xen.efi
application. This is all in efi land.
That then reads xen.cfg and boots the kernel and initrd defined in that
file.
Re: install Kernel and GRUB in chroot.
On Sat, Feb 03, 2024 at 01:17:05AM +0700, Dmitry wrote: > > Just copy files from LiveCD (it should have EFI/Boot/bootx64.efi) to the > ESP partition on the USB stick. > > As I understand right now `dd` command applied to a device will copy all > information including partitions table. Thus: Actually, cp (or even, horrors ;-) cat do the same. One advantage of dd is... > dd if=debian-xx.iso of=/dev/sdb bs=4M status=progress; sync ...this "status=progress". The other is "oflag=sync": for bigger sticks (and if you have tons of RAM) this last "sync" could take a long while, without giving you feedback of what's happening. And the third one (which it shares with cp but not with cat) is that sudo won't work in "sudo cat foo.img > /dev/bar" (unless you already are root, but that'd be cheating ;-) Cheers -- t signature.asc Description: PGP signature
Re: install Kernel and GRUB in chroot.
> Just copy files from LiveCD (it should have EFI/Boot/bootx64.efi) to the ESP partition on the USB stick. Yep. `dd` copy partitions table. Amazing. ``` dd will simply recreate the old partition scheme, as it is a bitwise copy & applies no 'intelligence' to the operation. ``` https://askubuntu.com/a/847533
Re: install Kernel and GRUB in chroot.
> Just copy files from LiveCD (it should have EFI/Boot/bootx64.efi) to the ESP partition on the USB stick. As I understand right now `dd` command applied to a device will copy all information including partitions table. Thus: dd if=debian-xx.iso of=/dev/sdb bs=4M status=progress; sync Would just create a copy of device, with FileSystem and PartitionsTable.
Re: install Kernel and GRUB in chroot.
On Fri 02 Feb 2024 at 21:12:30 (+0700), Dmitry wrote: > Going to read carefully. > > https://www.debian.org/releases/buster/amd64/ch04s03.en.html > > Interesting that Buster has more documentation than current release. It appears the balance has now been spun off into a wiki page, at https://wiki.debian.org/DebianInstaller/CreateUSBMedia Cheers, David.
Re: install Kernel and GRUB in chroot.
On 02/02/2024 21:06, Dmitry wrote: Need additional research what to do with a FlashStick with several partitions to make a LiveCD from it. Just copy files from LiveCD (it should have EFI/Boot/bootx64.efi) to the ESP partition on the USB stick.
Re: install Kernel and GRUB in chroot.
Going to read carefully. https://www.debian.org/releases/buster/amd64/ch04s03.en.html Interesting that Buster has more documentation than current release.
Re: install Kernel and GRUB in chroot.
> Do you want to install the OS on it? Eventually no, I do not want OS on the Flash Stick. The Flash Stick is only a testing place. I want OS at the SSD. Now I am wondering how to prepare the Flash Stick to write LiveImage on it. Because I already created a GPT table on that Flash and use debootstrap. Looks like need to create a new parition and copy LiveImage there. Need additional research what to do with a FlashStick with several partitions to make a LiveCD from it. > Do you want an encrypted system? No. I do not need this abstraction layer now.
Re: install Kernel and GRUB in chroot.
Am 02.02.2024 schrieb Dmitry : > I want OS at the SSD. Then the ESP should be on that SSD too.
Re: install Kernel and GRUB in chroot.
Max Nikulin schrieb: On a *removable* drive EFI/Boot/bootx64.efi (that is actually /usr/lib/shim/shimx64.efi.signed that loads grubx64.efi) may allow to boot without modification of boot entries in NVRAM. Yes, UEFI can (and must be able) to boot from a device without a boot entry in the UEFI. Otherwise you wouldn't be able to install an OS. You can boot such a device by simply selecting the device in the UEFI boot manager. Often it shows the model number of the device. Likely it is implementation-dependent whether a drive with GPT partition table is considered as a removable. For regular (internal) drives UEFI requires GPT. MBR should also work.
Re: install Kernel and GRUB in chroot.
On 02/02/2024 01:46, Dmitry wrote: 3. Now I want to boot using that Flash. 1. ESP is a partition that stores GRUB Binary. /boot/EFI/Name/grub64.eif On a *removable* drive EFI/Boot/bootx64.efi (that is actually /usr/lib/shim/shimx64.efi.signed that loads grubx64.efi) may allow to boot without modification of boot entries in NVRAM. Likely it is implementation-dependent whether a drive with GPT partition table is considered as a removable. For regular (internal) drives UEFI requires GPT. I do not suggest you to use msdos partition table that might be suitable for live media, not for installation with multiple partitions including Linux native file systems. 3. At the system partition there is a /boot/grub/grub.cfg There are 2 grub.cfg: for ESP and for /boot
Re: install Kernel and GRUB in chroot.
Am 01.02.2024 um 19:20:01 Uhr schrieb Tim Woodall:
> $ cat /boot/efi/EFI/XEN/xen.cfg
> [global]
> default=debian
>
> [debian]
> options=console=vga smt=true
> kernel=vmlinuz root=/dev/mapper/vg--dirac-root ro quiet
> ramdisk=initrd.img
>
>
> menuentry "Xen EFI NVME" {
> insmod part_gpt
> insmod search_fs_uuid
> insmod chain
> #set root=(hd1,gpt1)
> search --no-floppy --fs-uuid --set=root C057-BC13
> chainloader (hd1,gpt1)/EFI/XEN/xen.efi
> }
Then this file tells the boot loader about the /boot or / partition.
Is that the Xen virtualization software?
--
Gruß
Marco
Spam und Werbung bitte an ichschickerekl...@cartoonies.org
Re: install Kernel and GRUB in chroot.
On Thu, 1 Feb 2024, Marco Moock wrote:
Am 02.02.2024 um 01:46:06 Uhr schrieb Dmitry:
2. ==>BAM<== some how that binary knows the system partition.
That information is on the EFI partition, where the GRUB bootloader
binary also resides.
root@ryz:/boot/efi/EFI# cat /boot/efi/EFI/debian/grub.cfg
search.fs_uuid 5b8b669d-xyz root hd0,gpt2 #boot partition
set prefix=($root)'/grub'
configfile $prefix/grub.cfg
root@ryz:/boot/efi/EFI#
If that information is loaded, the kernel can be loaded from the boot
partition.
Are you sure that file does anything? I don't have one
drwxr-xr-x 2 root root 4096 Dec 31 2017 .
drwxr-xr-x 6 root root 4096 Dec 25 2019 ..
-rwxr-xr-x 1 root root 163840 Sep 11 2022 grubx64.efi
This finds my boot partition and then chainloads the XEN efi binary
which does have some config.
/boot/efi/EFI/XEN:
total 38204
drwxr-xr-x 2 root root 4096 May 5 2023 .
drwxr-xr-x 6 root root 4096 Dec 25 2019 ..
-rwxr-xr-x 1 root root 31132473 Aug 12 08:34 initrd.img
-rwxr-xr-x 1 root root 5283136 Aug 12 08:34 vmlinuz
-rwxr-xr-x 1 root root 138 May 5 2023 xen.cfg
-rwxr-xr-x 1 root root 2687456 Jun 20 2021 xen.efi
$ cat /boot/efi/EFI/XEN/xen.cfg
[global]
default=debian
[debian]
options=console=vga smt=true
kernel=vmlinuz root=/dev/mapper/vg--dirac-root ro quiet
ramdisk=initrd.img
menuentry "Xen EFI NVME" {
insmod part_gpt
insmod search_fs_uuid
insmod chain
#set root=(hd1,gpt1)
search --no-floppy --fs-uuid --set=root C057-BC13
chainloader (hd1,gpt1)/EFI/XEN/xen.efi
}
Re: install Kernel and GRUB in chroot.
On Fri, 2 Feb 2024, Dmitry wrote: Hi Tim. The community is so kind. So. I'm not exactly sure what you're doing. Understand how GRUB works, to boot myself. 1. Trying to install Debian on the Flash. 2. Use it by the Debootstrap. 3. Now I want to boot using that Flash. Looks like a caught the thread. 1. ESP is a partition that stores GRUB Binary. /boot/EFI/Name/grub64.eif 2. ==>BAM<== some how that binary knows the system partition. because grub64.efi understands the disk layout and looks for it. You can build your own I'm not giving any guarantees - look at the date on this file: $ ls -al test-uefi -rw-r--r-- 1 tim tim 341 Dec 31 2018 test-uefi $ cat test-uefi grub-mkimage -o bootx64.efi -p /EFI/BOOT -O x86_64-efi \ fat iso9660 part_gpt part_msdos \ normal boot echo linux configfile loopback chain \ efifwsetup efi_gop efi_uga \ ls search search_label search_fs_uuid search_fs_file \ gfxterm gfxterm_background gfxterm_menu test all_video loadenv \ exfat ext2 lvm mdraid09 mdraid1x diskfilter but that probably builds (or once worked) a .efi application that will successfully boot a system by searching for grub.cfg. I don't remember the details... I also have this - take with a pinch of salt - I wrote this learning about this system as you are trying to now... $ ls -al uefi-notes -rw-r--r-- 1 tim tim 2375 Dec 1 2018 uefi-notes 1 FDISK g - create a new empty GPT partition table p - create a primary partition +128M (size) t - change type 1 - EFI system p - create primary partition fill rest of disk vgcreate vg-uefi-boot /dev/sdb2 lvcreate -L 128M -n boot vg-uefi-boot lvcreate -l 100%FREE -n root vg-uefi-boot mke2fs -j /dev/mapper/vg--uefi--boot-boot mke2fs -j /dev/mapper/vg--uefi--boot-root mkdosfs /dev/sdb1 mount /dev/vg-uefi-boot/root /mnt/image/ debootstrap --variant=minbase stretch /mnt/image ftp://einstein/debian/ mount -o bind /proc /mnt/image/proc mount -o bind /dev /mnt/image/dev mount -o bind /sys /mnt/image/sys chroot /mnt/image /etc/kernel-img.conf apt-get update apt-get -y upgrade apt-get -y install sysvinit-core apt-get -y install openssh-server apt-get -y install ifupdown apt-get -y install grub-efi-amd64 apt-get -y install mdadm apt-get -y install lvm2 apt-get -y install linux-image-amd64 grub-install mkdir /boot/efi/EFI/BOOT cp /boot/efi/EFI/debian/grubx64.efi /boot/efi/EFI/BOOT/bootx64.efi update-grub (update root password) umount /boot/efi umount /boot EOF umount /mnt/image/proc umount /mnt/image/dev umount /mnt/image/sys umount /mnt/image/ vgchange -aln vg-uefi-boot (Installed firmware-realtek) mount /dev/vg-uefi-boot/root /mnt/image/ mount -o bind /proc /mnt/image/proc mount -o bind /dev /mnt/image/dev mount -o bind /sys /mnt/image/sys chroot /mnt/image mount -a umount -a exit umount /mnt/image/proc umount /mnt/image/dev umount /mnt/image/sys umount /mnt/image/ vgchange -aln vg-uefi-boot
Re: install Kernel and GRUB in chroot.
Am 02.02.2024 um 01:46:06 Uhr schrieb Dmitry: > 2. ==>BAM<== some how that binary knows the system partition. That information is on the EFI partition, where the GRUB bootloader binary also resides. root@ryz:/boot/efi/EFI# cat /boot/efi/EFI/debian/grub.cfg search.fs_uuid 5b8b669d-xyz root hd0,gpt2 #boot partition set prefix=($root)'/grub' configfile $prefix/grub.cfg root@ryz:/boot/efi/EFI# If that information is loaded, the kernel can be loaded from the boot partition. -- Gruß Marco Spam und Werbung bitte an ichschickerekl...@cartoonies.org
Re: install Kernel and GRUB in chroot.
Hi Tim. The community is so kind. So. > I'm not exactly sure what you're doing. Understand how GRUB works, to boot myself. 1. Trying to install Debian on the Flash. 2. Use it by the Debootstrap. 3. Now I want to boot using that Flash. Looks like a caught the thread. 1. ESP is a partition that stores GRUB Binary. /boot/EFI/Name/grub64.eif 2. ==>BAM<== some how that binary knows the system partition. 3. At the system partition there is a /boot/grub/grub.cfg 4. And at that /boot/grub/grub.cfg is UUID and etc. to start Booting. But the question is on the step 2. /boot/EFI/Name/grub64.efi knows where to start /boot/grub/grub.cfg that resides at the absolutely different partition. Interesting. But the question already asked. Now it possible to find the answer. Thank you!
Re: install Kernel and GRUB in chroot.
Am 02.02.2024 um 00:09:56 Uhr schrieb Dmitry: > I made experiments with a FlashDrive, and create GPT there, > if I want to use standard Debian Image how I should partition that > flash drive (MBR, GPT)? Do you want to install the OS on it? For the partition table, I recommend GPT. Do you want an encrypted system? > > Do you need a special configuration here or is the default just > > fine? > > Need just working one. But I am confusing about how GRUB would get a > plenty of things related to filesystem, kernel location and so on. That is being done be the installer. If you don't need special configuration, use the install process. It does everything for you. -- Gruß Marco Spam und Werbung bitte an ichschickerekl...@cartoonies.org
Re: install Kernel and GRUB in chroot.
Huge thanks. Your message starts the understanding. And as well give a plenty of texts to read. > EFI/debian/grub.cfg on the EFI System Partition contains filesystem UUID where grub files reside. All parts are simple But when compounding them together become messy. In the Manjaro: /boot/EFI/Majaro/grub64x.efi - binary to start by UEFI. /boot/grub/grub.cfg - shell (?) script with configurations. /boot/vimlinuz.* - the kernel. And if call a `lsblk`. Only a /boot/efi with a binary is a separate partiton. Things become more clear.
Re: install Kernel and GRUB in chroot.
On Thu, 1 Feb 2024, Dmitry wrote: Greetings! After: 1. Creating GPT table and GPT partition with fdisk. 2. Copy data with a debootstrap. 3. Chroot into newly creating system. I need to prepare that system for booting. 1. Install Kernel. 2. Install GRUB and Configure. 3. Add changes to UEFI to start booting. And at the point two (Install GRUB) I a little bit confused. 1. Need to create ESP, and put GRUB there. 2. Need to configure GRUB to select appropriate kernel and ramdisk. I'm not exactly sure what you're doing. But the "trick" to doing most of this in a chroot is to bind mount /dev, /proc, /sys and /run into the chroot. Then things like installing the kernel, building the initrd etc (usually) just work. "Add changes to UEFI to start booting" depends on the actual hardware that will boot. If you're preparing images on one system to boot on another then that bit you'll have to solve by booting the hardware. I'd probably pick a live distro but it's theoretically[1] possible to generate your own bootx64.efi that will then boot your system. Once it's booted you can then use the normal tools to replace it with a more easily maintained debian solution. [1] Not just theoretical, I've actually done it once long ago.
Re: install Kernel and GRUB in chroot.
> Why don't you use the normal setup? Spend a lot of time on research, it would be nice to finish. I made experiments with a FlashDrive, and create GPT there, if I want to use standard Debian Image how I should partition that flash drive (MBR, GPT)? > Do you need a special configuration here or is the default just fine? Need just working one. But I am confusing about how GRUB would get a plenty of things related to filesystem, kernel location and so on. > If you create a separate boot partition (do you really need it?), it must be mounted at /boot. Here where the mess starts. How GRUB and Kernel would get information about all this mounting points during the Boot.
Re: install Kernel and GRUB in chroot.
On 01/02/2024 22:54, Marco Moock wrote: Am 01.02.2024 schrieb Dmitry: Use gdisk for that. You can create an EFI partition there. Choose Type EFI (EF00), 100MB. Format it with FAT32. 550MiB is recommended in "Preparing your ESP" http://www.rodsbooks.com/linux-uefi/#installing see also https://www.rodsbooks.com/gdisk/advice.html#esp_sizing https://fedoraproject.org/wiki/Changes/BiggerESP 2. Need to configure GRUB to select appropriate kernel and ramdisk. Do you need a special configuration here or is the default just fine? EFI/debian/grub.cfg on the EFI System Partition contains filesystem UUID where grub files reside. After installing grub check that NVRAM has an appropriate entry efibootmgr -v How GRUB would understand where to be install and where is the kernel? It loads files from filesystem on the specified partition. Unlike for BIOS device blocks are not involved.
Re: install Kernel and GRUB in chroot.
Am 01.02.2024 schrieb Dmitry : Why don't you use the normal setup? It does many tasks for you. > After: > 1. Creating GPT table and GPT partition with fdisk. Use gdisk for that. You can create an EFI partition there. Choose Type EFI (EF00), 100MB. Format it with FAT32. > And at the point two (Install GRUB) I a little bit confused. > > 1. Need to create ESP Do that before the install with gdisk. > and put GRUB there. That is done automatically if it is mounted at /boot/efi. > 2. Need to configure GRUB to select appropriate kernel and ramdisk. Do you need a special configuration here or is the default just fine? > How to create a ESP partition and mount it to /boot? That must be mounted to /boot/efi. If you create a separate boot partition (do you really need it?), it must be mounted at /boot. > How GRUB would understand where to be install and where is the kernel? It chooses by the path. grub-install is the command, no device as parameter.
