/boot/grub2/grub.cfg vs /boot/efi/EFI/centos/grub.cfg

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ng0177
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/boot/grub2/grub.cfg vs /boot/efi/EFI/centos/grub.cfg

Post by ng0177 » 2020/08/01 10:09:53

Any ideas as to which of these two is actually used and which one could potentially be deleted on an UEFI system running 8.2? Thanks!

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TrevorH
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Re: /boot/grub2/grub.cfg vs /boot/efi/EFI/centos/grub.cfg

Post by TrevorH » 2020/08/01 11:13:56

/boot/grub2/grub.cfg is used on non-UEFI systems so if you do not have a /sys/firmware/efi on your system then that's the one in use. If you do have /sys/firmware/efi then you are using UEFI and the path is under /boot/efi instead.
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
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ng0177
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Re: /boot/grub2/grub.cfg vs /boot/efi/EFI/centos/grub.cfg

Post by ng0177 » 2020/08/01 12:27:52

Thanks for the swift reply, it saves me a lot of time. To (re-)install grub, I guess

Code: Select all

sudo grub2-install
should be avoided and

Code: Select all

sudo yum reinstall grub2-efi grub2-efi-modules shim
preferred.

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TrevorH
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Re: /boot/grub2/grub.cfg vs /boot/efi/EFI/centos/grub.cfg

Post by TrevorH » 2020/08/01 14:46:46

Why do you think you need to reinstall grub? It's almost never required.

If you are suffering from the recent boothole fix problem then that's not the right solution, see https://access.redhat.com/solutions/5272311 instead
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

ng0177
Posts: 16
Joined: 2017/10/07 13:59:47

Re: /boot/grub2/grub.cfg vs /boot/efi/EFI/centos/grub.cfg

Post by ng0177 » 2020/08/01 16:12:00

Maybe, symptoms are a black screen since the last update. I can still cross boot in from another OS e.g. Arch (guess that is what a hacker would do) but get:

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# yum downgrade shim\* grub2\* mokutil
Last metadata expiration check: 3:23:06 ago on Sat 01 Aug 2020 02:44:31 PM CEST.
Package shim-x64 of lowest version already installed, cannot downgrade it.
Package grub2-tools-efi of lowest version already installed, cannot downgrade it.
Package grub2-common of lowest version already installed, cannot downgrade it.
Package grub2-tools of lowest version already installed, cannot downgrade it.
Package grub2-pc of lowest version already installed, cannot downgrade it.
Package grub2-pc-modules of lowest version already installed, cannot downgrade it.
Package grub2-tools-extra of lowest version already installed, cannot downgrade it.
Package grub2-tools-minimal of lowest version already installed, cannot downgrade it.
Package grub2-efi-x64 of lowest version already installed, cannot downgrade it.
Package grub2-efi-aa64-modules of lowest version already installed, cannot downgrade it.
Package mokutil of lowest version already installed, cannot downgrade it.
Dependencies resolved.
Nothing to do.
Complete!

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TrevorH
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Re: /boot/grub2/grub.cfg vs /boot/efi/EFI/centos/grub.cfg

Post by TrevorH » 2020/08/01 16:26:16

Sounds more like you need to go read the thread about the latest updates being broken and how to back them out.

viewtopic.php?f=57&t=75187
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

ng0177
Posts: 16
Joined: 2017/10/07 13:59:47

Re: /boot/grub2/grub.cfg vs /boot/efi/EFI/centos/grub.cfg

Post by ng0177 » 2020/08/01 18:07:39

Appreciate. Hopefully, they will find a fix that applies through an update. I keep side booting until then. 8-)

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