==================== UEFI troubleshooting ==================== Successfully installed in legacy mode, but had to change some xen parameters ---------------------------------------------------------------------------- **Note**: If you make changes, you must boot from “Partition 1” explicitly from UEFI boot menu. **Change the xen configuration on a USB media** 1. Attach the usb disk, mount the EFI partition (second partition available on the disk) 2. Open a terminal and enter the command ``sudo su -``. Use your preferred text editor (e.g ``vi``) to edit your xen config (``EFI/BOOT/grub.cfg``): .. code:: bash vi EFI/BOOT/grub.cfg 3. Change the ``multiboot2 /images/pxeboot/xen.gz`` line to add your xen parameters on the boot entry of your choice 4. Install using your modified boot entry **Change xen configuration directly in an iso image** 1. Set up a loop device (replacing ``X`` with your ISO’s version name): ``losetup -P /dev/loop0 Qubes-RX-x86_64.iso`` 2. Mount the loop device: ``sudo mount /dev/loop0p2 /mnt`` 3. Edit ``EFI/BOOT/grub.cfg`` to add your params to the ``multiboot2 /images/pxeboot/xen.gz`` line 4. Save your changes, unmount and dd to usb device Installation freezes before displaying installer ------------------------------------------------ If you have an Nvidia card, see also `Nvidia Troubleshooting `__. Installation from USB stick hangs on black screen ------------------------------------------------- Some laptops cannot read from an external boot device larger than 8GB. If you encounter a black screen when performing an installation from a USB stick, ensure you are using a USB drive less than 8GB, or a partition on that USB lesser than 8GB and of format FAT32. Installation completes successfully but then system crash/restarts on next boot ------------------------------------------------------------------------------- Some Dell systems and probably others have `another bug in UEFI firmware `__. These systems need ``efi=attr=uc`` enabled at all times. Although this is enabled by default in the installer, it is disabled after the first stage of a successful install. You can re-enable it either as part of the install process: 1. Perform installation normally, but don’t reboot the system at the end yet. 2. Go to ``tty2`` (Ctrl-Alt-F2). 3. Execute: .. code:: bash sed -i -e 's/ucode=scan/\0 efi=attr=uc/' /mnt/sysimage/boot/efi/EFI/qubes/grub.cfg 4. Go back to ``tty6`` (Ctrl-Alt-F6) and click ``Reboot``. 5. Continue with setting up default templates and logging in to Qubes. Or if you have already rebooted after the first stage install and have encountered this issue, by: 1. Boot Qubes OS install media into :ref:`rescue mode ` 2. Press ‘3’ to go to the shell 3. Find and mount the EFI system partition. (replace ``/dev/sda`` with your disk name. If unsure, use the ``lsblk`` command to display a list of disks): ``fdisk -l /dev/sda | grep EFI`` The output should look like this: ``/dev/sda1 2048 1230847 1228800 600M EFI System`` Then mount it: ``mkdir -p /mnt/sysimage/boot/efi mount /dev/sda1 /mnt/sysimage/boot/efi`` 4. Execute: .. code:: bash sed -i -e 's/ucode=scan/\0 efi=attr=uc/' /mnt/sysimage/boot/efi/EFI/qubes/grub.cfg 5. Type ``reboot``. 6. Continue with setting up default templates and logging in to Qubes. Boot device not recognized after installing ------------------------------------------- Some firmware will not recognize the default Qubes EFI configuration. As such, it will have to be manually edited to be bootable. 1. Boot Qubes OS install media into :ref:`rescue mode ` 2. Press ‘3’ to go to the shell 3. Find and mount the EFI system partition. (replace ``/dev/sda`` with your disk name. If unsure, use the ``lsblk`` command to display a list of disks): ``fdisk -l /dev/sda | grep EFI`` The output should look like this: ``/dev/sda1 2048 1230847 1228800 600M EFI System`` Then mount it: ``mkdir -p /mnt/sysimage/boot/efi mount /dev/sda1 /mnt/sysimage/boot/efi`` 4. Copy ``grubx64.efi`` to the fallback path: .. code:: bash cp /mnt/sysimage/boot/efi/EFI/qubes/grubx64.efi /mnt/sysimage/boot/efi/EFI/BOOT/bootx64.efi 5. Type ``reboot`` "Qubes" boot option is missing after removing / attaching a disk or updating the BIOS ------------------------------------------------------------------------------------- 1. Boot Qubes OS install media into :ref:`rescue mode ` 2. Press ‘3’ to go to the shell 3. Create boot entry in EFI firmware (replace ``/dev/sda`` with your disk name and ``-p 1`` with ``/boot/efi`` partition number): .. code:: bash efibootmgr -v -c -u -L Qubes -l /EFI/qubes/grubx64.efi -d /dev/sda -p 1 Accessing installer Rescue mode on UEFI --------------------------------------- Choose “Rescue a Qubes OS system” from grub2 boot menu.