fixes for efi eurolinux 8.10 (#95)

Author: AlexBaranowski

docs/assets/wrong-efi/reinstall.png

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+# Black Screen After update to EuroLinux 8.10 - EFI problem
+
+## Background
+
+We are deeply sorry to inform you that one of the packages in EuroLinux 8.10
+created a severe mistake in the boot configuration. The package grub2-efi-x64
+was copied from a never-released beta repository, and it was not supposed to be
+there in that version.
+
+
+If you updated your system:
+
+- before May 28th, 13 CET
+- and you are using EFI
+
+The following error might appear after booting your system.
+
+```
+error: file `/EFI/eurolinux/grubx64.efi` Not Found.
+```
+
+and other similar errors, like:
+
+```
+StartImage failed
+```
+
+Generally speaking, the system won't boot into the bootloader (GRUB).
+Depending on your UEFI software, you might see different error messages.
+
+
+Depending on your UEFI software you might be able to boot system normally. If
+you can boot system you can fix the problem by reinstalling the `grub2-efi-x64`
+package. 
+
+![Example message screen](../assets/wrong-efi/wrong-efi-screen.png)
+
+## When this problem does not occur
+
+- If you are using a VM that does not use EFI you won't have this problem
+- If you are using legacy BIOS and the system was installed as legacy BIOS
+- Container images and other images
+
+
+## Update after May 28th, 12 CET
+
+
+If you are updating your system with a repository synced after May 28, 13 CET,
+you should not have this problem. The package was removed and overwritten from
+the repository, and the proper package was added.
+
+
+## Updated but not rebooted system
+If you updated but have not rebooted the system -> please reinstall the
+grub2-efi-x64 package and kernel packages:
+
+```
+sudo yum clean all
+sudo yum reinstall -y `kernel*` `grub2*`
+```
+
+## ISO files
+
+The ISO files were updated, and the previous ISO was removed. The new ISO is
+supposed to be released today (May 28th).
+
+## Revert from backup/snapshot
+
+If you can, please revert from the backup or snapshot to version 8.9. The
+update process now contains overwritten, updated and proper packages, and this
+problem will not occur.
+
+## Rescue system with wrong EFI from a live CD.
+
+1. Download LiveISO CD
+2. Change boot order (if necessary)
+3. Mount ISO/Create ISO on the pendrive
+4. Start system from ISO
+5. Mount the EFI partition
+6. Copy the EFI files
+7. Run system normally
+8. Reinstall kernel-core and grub2-efi-x86
+
+
+
+## Download LiveISO CD
+
+One of the smallest ISO and well-known projects is Rescatux. You can download
+it from:
+https://sourceforge.net/projects/rescatux/files/rescatux-0.74/rescatux-0.74.iso/download
+
+
+You can use different ISOs, such as our Desktop Live or Ubuntu.
+
+## Change the boot order (if necessary)
+
+Changing the boot order might be necessary for both VM and Physical Machines.
+
+## Mount ISO/Create ISO on pendrive
+
+Mount rescue ISO to a VM. For physical machines, create a bootable pendrive
+with the ISO. The process is similar to creating a bootable pendrive for
+installation.
+
+After mounting or inserting the pen drive, start the rescue/live CD system.
+
+## Starting rescuetux or other livecd
+
+You can safely start Rescuetux or another live CD. The process is similar to
+getting a standard desktop. You can safely skip any questions and programs and
+get straight to the terminal.
+
+
+![Rescue 1](../assets/wrong-efi/rescue-tux-1.png)
+
+## Find and mount the EFI partition
+
+Finding an EFI partition is quite straightforward use one of the following commands:
+
+```
+sudo lsblk
+```
+
+Example efi partition output
+
+```
+/dev/nvme0n1p5: UUID="2A1E-AC26" TYPE="vfat" PARTLABEL="EFI System Partition" PARTUUID="6b15bd77-bb2e-4393-9fbb-445625660679"
+```
+
+or
+
+```
+lsblk -f
+```
+Example EFI partition output
+
+```
+vda1 vfat               776-93D0
+```
+
+After finding the EFI partition, mount it to a temporary location. In the
+example bellow, we are using `/mnt` as a temporary location, and partition is
+the `/dev/vda1`
+
+```
+sudo mount /dev/vda1 /mnt
+```
+
+Confirm the EFI partition is mounted correctly and contains EFI directory
+
+```
+cd /mnt/
+ls
+```
+
+The output should contains at least an EFI directory
+
+```
+EFI
+```
+
+## Copy the EFI files
+
+```
+sudo cp -r /mnt/EFI/redhat/* /mnt/EFI/eurolinux/.
+```
+
+
+## Reboot system
+
+Depending on the live CD/ISO you used, you might need to reboot the system or exit the live CD.
+
+```
+sudo reboot
+```
+in most cases, is enough. You can also shut down the system with shutdown -h now.
+
+
+Before starting the EuroLinux system, remember to remove the rescue/LiveCD ISO
+ISO or pendrive.
+
+
+The whole process is as simple as the one on the screenshot:
+
+![Rescue 2](../assets/wrong-efi/rescue-tux-2.png)
+
+## Running the system and reinstalling the packages
+
+
+After rebooting the system you should be able to boot into the system in normall state. You can now reinstal the kernel
+and grub packages.
+
+```
+sudo yum clean all
+sudo yum reinstall -y `kernel*` `grub2*`
+```
+
+![Reinstall](../assets/wrong-efi/reinstall.png)
+
+## Summary
+
+
+Once more, we are deeply sorry for the inconvenience. The bug skipped our
+testing and escaped into the public as we were changing the test structure to
+support new features, including Secure Boot for EuroLinux 9.
+
+
+We are working on improving our testing process to avoid such mistakes in the
+future.
+
+
+If you have any questions or need help, please contact us at support at
+euro-linux.com. We will dispatch an engineer for a one-on-one session to assist
+you.