Upgrade 8>9 stuck in "Welcome to Grub"

[Mechanix]

Hi,
my Proxmox server is installed on a nvme0n1 SSD (standard partitions) and has a storage zpool of 4x8TB
I've followed the upgrade guide step-by-step, the pre-checks completed all with no errors. After rebooting the server it stuck at grub "Welcome to Grub" and reboots into BIOS after a while.
Since I got a the Legacy BIOS:

[ -d /sys/firmware/efi ] && echo UEFI || echo BIOS
BIOS

efibootmgr -v 
EFI variables are not supported on this system

all posts I've found couldn't fix the issue.

I've bootet with the ISO "Terminal Debug" and could chroot into the installation and run:

grub-install /dev/nvme0n1
update-grub
update-initramfs -u -k all

but that didn't help although no errors occured.

Now, I thought something changed in the BIOS. Tried different settings (legacy/uefi) with no success.

Strangely lsblk shows a small FAT32 partition (see screenshot)

So I'm stucked. Any help is much appreciated!!!

 

[fabian]

any chance you can switch to UEFI booting? if not, you can still try "proxmox-boot-tool" to install grub onto the ESP, and boot from there. on some systems that works around issues grub might have with larger disks.

 

[Mechanix]

Thanks for your reply. I managed to boot the server by

apt reinstall grub-efi-amd64

and added a corresponding fstab entry:

UUID=539B-6D66    /boot/efi    vfat    umask=0077    0    1

fix also found here