Failed to craete EFI Boot variable entry: Invalid argument


New Member
Jul 20, 2023

trying to install VE 8.0 on a QNAP TS-251+ : 2 x 4 TB disks ZFS Raid-1 via USB stick UEFI boot

At the end on installing the boot loader it errors out with:

Failed to craete EFI Boot variable entry: Invalid argument
bootloader setup errors:
unable to init ESP and install proxmox-boot loader on /dev/sda2



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Seems an issue with the BIOS, QNAP tags TS-251+ as legacy and not UEFI, although the BIOS show UEFI-Boot.

Based on testing, ZFS-RAID-1 on root also supports on legacy boot the boot loader on both devices? Though its only available with UEFI?

at the end it was with high probability to boot from the Proxmox USB stick not in UEFI mode (Boot option #3)


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