Known Issues

Installation

Bootloader Installation Fails (Non-UEFI Boot)

Error: "The bootloader could not be installed"

This error appears on the final Calamares installation screen when the ISO is booted in legacy BIOS mode instead of UEFI mode.

Fix: Ensure your virtual machine or physical hardware is set to boot in UEFI mode:

• VirtualBox: Settings → System → Enable EFI (special OSes only)
• VMware Workstation: VM → Settings → Options → Advanced → Firmware type → UEFI
• QEMU/KVM: Add -bios /usr/share/ovmf/OVMF.fd or use UEFI firmware
• Physical hardware: Enter BIOS/firmware settings and switch from Legacy/CSM to UEFI boot

Why: NubiferOS uses LUKS full-disk encryption with GPT partitioning, which requires UEFI firmware for reliable GRUB installation. Legacy BIOS boot with GPT requires a special bios_grub partition that may not be created correctly by the installer.

Boot & Login

LUKS Passphrase Prompted Three Times on Boot

Symptom: During boot, you are asked to enter your LUKS passphrase three times before reaching the login screen.

This is expected behavior in the current release, not a bug. Each prompt is decrypting a different layer of the system.

What's happening:

1. First prompt (GRUB): GRUB decrypts the /boot partition to load the kernel and initramfs
2. Second prompt (initramfs): The kernel's initramfs decrypts /boot again during early system initialization — GRUB's decryption does not carry over to the kernel
3. Third prompt (initramfs): The initramfs decrypts the root (/) partition to mount the full filesystem

Fix: This will be resolved in a future release. The planned approach is to embed a keyfile in the initramfs so that once GRUB decrypts /boot, the remaining partitions unlock automatically. See our Disk Encryption roadmap for details.

Why: NubiferOS encrypts both /boot and root with LUKS to provide full disk encryption with no unencrypted partitions. The trade-off in the current release is multiple passphrase prompts because GRUB and the kernel's initramfs operate independently and cannot share decryption state.

Failed LUKS Password Falls Through to GRUB Rescue

Error: After entering an incorrect LUKS passphrase, the system drops to a grub rescue> prompt instead of re-prompting for the password.

This can appear as if the bootloader is broken, but the system is actually working correctly — GRUB just can't decrypt the disk and has nowhere to go.

Fix: Reboot the machine and enter the correct LUKS passphrase:

• Power off or press Ctrl+Alt+Del to restart
• When prompted for the LUKS passphrase, enter it carefully
• If you're unsure of your passphrase, check Caps Lock and keyboard layout

Why: NubiferOS encrypts the entire disk including /boot with LUKS. When GRUB fails to decrypt the disk with the provided passphrase, it cannot load the kernel or initramfs, so it falls back to its rescue shell. This is a GRUB limitation — it does not gracefully retry the passphrase prompt on failure.

Workspaces

No issues reported yet.

Cloud Tools

No issues reported yet.

Updates

APT Update Fails with "Hash Sum Mismatch"

Error: sudo apt update fails with a hash sum mismatch error for the NubiferOS package repository.

E: Failed to fetch https://packages.nubiferos.org/dists/nubiferos/main/binary-amd64/Packages.gz
   Hash Sum mismatch

This happens when the APT repository's Release file and Packages.gz are temporarily out of sync due to CDN caching. After a new package version is published, CloudFront may serve the updated Packages.gz but still have the old Release file cached (or vice versa).

Fix: Wait a few minutes for the CDN cache to expire (up to 5 minutes), then clear your local APT cache and retry:

sudo apt clean
sudo apt update

Why: The NubiferOS package repository is served through CloudFront with a 5-minute cache TTL. When new packages are published, there is a brief window where the cached metadata files can be out of sync. Clearing the local APT cache ensures a fresh download of all repository metadata.

Other

No issues reported yet.