Grub and UEFI, installation guide

If anyone is interested I have installed Slackware 15 two or three times using the below guide and it all worked very well:

itkb.ro - IT knowledge base
linux :: slackware 14.2 with grub and uefi

https://www.itkb.ro/kb/linux/slackwa...-grub-and-uefi

....just to say as well...

if, for instance, you are installing from USB make sure you choose your boot device from the UEFI section in the BIOS device list and not from the legacy section, it will probably be listed in both with the same label. During setup, once you have formatted your swap, your root and whatever else it should detect an EFI partition and offer to format it for you. If it doesn't and you carry on you will likely run into trouble - it won't offer to install elilo (even though you will skip it as per the instructions) and if you then carry on to the end of the install and follow the shell instructions, # chroot etc, they will also fail and your system won't boot.

One other thing, forgive me if you know already, if you do follow the instructions correctly and everything goes well, type exit (from where you did chroot in) and then reboot.

Sorry if I'm not too technical with this, I don't really have enough knowledge to explain all that is going on here, but if you follow what I say you should be fine.

Hope it helps someone anyway.

Thanks for the tips!

Originally Posted by rkfb if, for instance, you are installing from USB make sure you choose your boot device from the UEFI section in the BIOS device list and not from the legacy section, it will probably be listed in both with the same label. During setup, once you have formatted your swap, your root and whatever else it should detect an EFI partition and offer to format it for you. If it doesn't and you carry on you will likely run into trouble - it won't offer to install elilo (even though you will skip it as per the instructions) and if you then carry on to the end of the install and follow the shell instructions, # chroot etc, they will also fail and your system won't boot.

If this should happen,it is worth noting that you may easily recover without reinstalling everything (assuming your partitioning was originally correct).

One easy way is to simply reboot into the install media from the UEFI device as noted above. Then run setup as if performing a new install and select partitions, at which point it should detect the EFI partition and offer to format it for you if it is not already formatted. Continue installation but skip over package selection and other options until you are offered the LILO and ELILO options and configure those as necessary... reboot.

It has also been my experience that you may safely install both LILO and ELILO which will allow booting via EFI or Legacy.

Hope that helps!

UPDATE: As pointed out below by colorpurple21859, be sure to NOT reformat the / (root) or other already installed partitions when selecting partitions!

One easy way is to simply reboot into the install media from the UEFI device as noted above. Then run setup as if performing a new install and select partitions, at which point it should detect the EFI partition and offer to format it for you if it is not already formatted.

If you use this method to recover, make sure you select no when asked to format root partition at the "select target" stage.

I'm pretty sure I've followed all the fore mentioned steps, followed the code from https://www.itkb.ro/kb/linux/slackwa...-grub-and-uefi more than 3Xs and I keep getting: "grub-install: error: unknown filesystem"

#grub-install --target=x86_64-efi --efi-directory=/boot/efi bootloader=id=grub
Installing for x86_64-efi platform.
grub-install: error: unknown filesystem

Why is grub-install failing, with an unknown filesystem error? I've tried formatting Partitions with fdisk & cfdisk, gone as far as merely doing 3 Partitions EFI, /swap, /

You could face the error described in this thread
https://www.linuxquestions.org/quest...l-4175722697/?

Workaround in the last posts.