Re: [gentoo-user] Fun with systemd-boot

[Joost Roeleveld <joost@antarean.org>]

----------------------- Original message -----------------------
From: Alan Mackenzie <acm@muc.de>
To: gentoo-user@lists.gentoo.org
Date: Wed, 18 Dec 2024 14:41:00 +0100
----------------------------------------------------------------

> Hello, Arsen.
>
> On Wed, Dec 18, 2024 at 13:50:09 +0100, Arsen Arsenović wrote:
>> Hi Alan,
>
>> Alan Mackenzie <acm@muc.de> writes:
>
>> > Hello, Gentoo.
>
>> > I've been having fun with systemd-boot.
>
>> > On my new (2024-08) machine, on Friday 2024-12-06, I suddenly noticed
>> > that my /boot partition was empty, I can't remember why I looked at it.
>> > I am quite sure I didn't empty it myself. There then followed a couple
>> > of hours where I restored the boot manager, kernels, and the boot
>> > configuration. Thankfully, it booted again the next time I tried.
>
>> > On my old machine, I've been noticing over the past weeks that only two
>> > older kernels have been offered for booting, despite me installing later
>> > kernels to /boot/EFI/gentoo, and configuring them in /boot/loader.
>
>> You don't need to do that manually, installkernel should handle it for
>> you. You should get installkernel[systemd,systemd-boot].
>
> No, I don't need to learn a new abstruse command (which might do anything
> apart from its prime function) when cp works 100%.
>
>> > It all became clear yesterday and today. bootctl install had
>> > installed itself to /dev/nvme1n1p1 rather than /boot (which I have
>> > mounted on /dev/nvme0n1p1).
>
>> This would mean you mounted /dev/nvme1n1p1 on /efi:
>
>> --esp-path=
>> Path to the EFI System Partition (ESP). If not specified,
>> /efi/, /boot/, and /boot/efi/ are checked in turn. It is
>> recommended to mount the ESP to /efi/, if possible.
>
> I have never knowingly mounted anything on /efi. Even if it was by
> accident, somehow, I certainly wouldn't have done it on both my old and
> new machines. And why the partition on nvme1?
>
>> You should have one ESP mounted at any time, and mounted at /efi. The
>> rest should work fine.
>
> I've got /dev/nvme0n1p1 mounted on /boot. That should work.
>
>> > Both of these partitions are EFI system partitions. It also clogged
>> > up my UEFI boot sequence with lots of extra entries, leaving nvme1
>> > rather than nvme0 the prime EFI system partition for booting with.
>
>> UEFI boot order entries are only created as part of 'bootctl install' so
>> this would mean you ran it many times.
>
> That's possible, though I don't remember now.
>
>> It only needs to be ran once. To update the bootloader, you'd use
>> 'bootctl update', to add/remove entries you'd use kernel-install.
>
>> > I've had a look at the manual page for bootctrl. It doesn't mention any
>> > way of specifying which EFI partition will get written to, and doesn't
>> > seem to mention that it changes the UEFI BIOS settings. Or maybe it
>> > does. It's a vague, poor quality manual.
>
>> That'd be --esp-path.
>
> Thanks! Though just /boot should work.
>
>> WRT changing UEFI settings, this is a necessity for UEFI boot -
>> grub-install does the same thing.
>
> I've always set the boot devices in the BIOS settings - including an
> entry for my DVD device, enabling me to install Gentoo. :-)
>
>> > I don't need all this. Booting should not be fun. It should be boring,
>> > boring, boring. Boring and dependable.
>
>> > Could somebody perhaps suggest a better boot loader to me? I need to be
>> > able to chose between several kernels at booting time, but I certainly
>> > don't want something "refined" like grub - I just need what I thought
>> > systemd-boot actually was before yesterday.
>
>> I suspect your problem lies elsewhere. What partitions are you
>> mounting? How are you installing kernels?
>
> I mount an EFI partition on /boot, along with several LVM partitions on /
> and subdirectories. I install kernels with cp from
> /usr/src/linux-x.y.z-gentoo/arch/x86/boot/bzImage to /boot/EFI/gentoo/,
> with a suitable new name. Then I add a new configuration file for the
> new kernel in /boot/loader/Entries.

For sys-boot/refind:

# ls /boot/EFI/Gentoo/
gentoo_6_6_62.efi

I include the initramfs and commandline into the kernel image.
But you can specify initrd seperately if needed by adding extra menu-entries.

--
Joost