EFI Boot Order Rewrite
Hello,
we are running CentOS Stream 8 on some of our dedicated servers. On the newer servers that boot with efi, the system that is installed with the default properties in the ISO installer writes itself to the top of the efi boot order. This seems to happen every time after bootup.
Since we run all our systems with efi network boot as the first boot option for rescue operation, this would be a significant problem for the future if the behavior cannot be turned off.
I have already checked the use of efibootmgr and some of the related grub settings such as GRUB_DEFAULT and GRUB_SAVEDEFAULT (which may have nothing to do with it). On Debian, I found a debconf option that prevents updating nvram. This seems to prevent the described behavior.
Does anyone have an idea for this problem?
With kind regards Florian
3 thoughts on - EFI Boot Order Rewrite
Florian Bauer wrote>
I had a similar issue with EFI booting with CentOS 7 a while ago – my ‘fix’ was to add something to the %post section of the kickstart file to use efibootmgr to set ‘EFI Network’ as the first device in the EFI BootOrder – which seemed to work OK for subsequent boots
James Pearson
Hi,
Thank you for your answer. That would only solve the problem at initial bootup but not for already installed systems.
Inserting such a solution into a late running service would be no option due to it’s destroying the boards storage over time because of the many writes.
On Debian/Ubuntu, there are a couple of grub2 debconf parameters. Unfortunately, there seems to be no such system like debconf for package level configuration properties iirc.
Kind regards Florian
Florian Bauer>
I’m pretty sure I only had to run efibootmgr once (at install time in my case) – and the boot order was fixed for all subsequent reboots (don’t currently have a setup that does this at the moment, so can’t check)
James Pearson