installboot will override efi/boot/bootx86.efi and efi/openbsd/bootx86.efi when it runs. it will create a new boot entry if installboot uses -c and there isn't already one for OpenBSD.
My arm64 X13s dualboots with Windows, and I have efi/microsoft/boot/bootmgr.efi and efi/openbsd/bootaa64.efi. When I go to the boot options, I get OpenBSD, Windows, and "disk" which will simply boot efi/boot/bootaa64.efi. No matter when I do an installboot, Windows will boot just fine. -peter On 2026 May 16 (Sat) at 09:50:18 -0700 (-0700), Heppler, J. Scott wrote: :I was under the impression that installing to the preformated OpenBSD :area bypassed OpenBSD installing an EFI Boot option. Does OpenBSD :installboot overwrite a previous Linux Grub install? : :In any event, the changes you describe should make Grub a more viable :option which is not how faq4 reads. : :On May 16, 2026: 16:27, Peter Hessler wrote: :> Yes this is somewhat recent change, started happening in 7.7 (October :> 2024). Thankfully you don't need to rename anything, so updating OpenBSD :> and/or Linux shouldn't have any negative effect on this. :> :> On amd64 and arm64 installboot also tries to install an EFI Boot Option :> (also 7.7, Feb 2025) to directly boot OpenBSD, without needing to modify :> Grub (or Windows bootloaders, etc). :> :> -peter :> :> :> On 2026 May 16 (Sat) at 06:59:39 -0700 (-0700), Heppler, J. Scott wrote: :> :Hi Peter, :> : :> :Installboot installing /boot/efi/openbsd/BOOTX64.EFI would also work :> :with Fedora derivatives. Is /boot/efi/BOOTX64.EFI -> :> :/boot/efi/openbsd/BOOTX64.EFI a recent change? Previouly, I attempted :> :to rename BOOTX64.EFI to BSD_BOOTX64.EFI and it resulted in the failure :> :of kernel relinking (KARL). :> : :> :Reference this forum thread: :> :https://daemonforums.org/showthread.php?t=12219 :> : :> : :> :On May 16, 2026: 09:24, Peter Hessler wrote: :> :> as long as the EFI partition is large enough (which I assume Linux/grub :> :> will create), installboot is supposed to install /boot/efi/openbsd/BOOTX64.EFI. :> :> Nicely up to date, won't be stomped on by other bootloaders, etc. :> :> :> :> I don't think you would even need to manually copy or edit that :> :> partition. :> :> :> :> :> :> On 2026 May 15 (Fri) at 12:31:34 -0700 (-0700), Heppler, J. Scott wrote: :> :> :Re: GRUB is reported to usually fail. :> :> : :> :> :This is misleading at best. :> :> : :> :> :OpenBSD can easily and reliably be booted from Grub installed on a Debian, :> :> :Debian Derivative or Arch Linux using Grub installed per the wiki. :> :> : :> :> :Essentially, the EFI partition is used in common with both Operating systems. :> :> : :> :> :The most time efficient way to install to a single disk is to install Linux :> :> :first and manually partition: :> :> :Partition1 = EFI :> :> :Partition2 = Linux / :> :> :Partition3 = Linux swap :> :> :Partition4 = allocated to OpenBSD :> :> : :> :> :After the linux install, use the native partition manager in Linux, fdisk or :> :> :gparted, to set Partition4 to type OpenBSD(data). :> :> : :> :> :Install OpenBSD to the OpenBSD area. :> :> : :> :> :Next boot back into Linux and download the OpenBSD "BOOTX64.EFi" file and :> :> :install to /boot/efi/. :> :> : :> :> :Edit /etc/grub.d/40_custom to: :> :> : :> :> :#!/bin/sh :> :> :exec tail -n +3 $0 :> :> :# This file provides an easy way to add custom menu entries. Simply type the :> :> :# menu entries you want to add after this comment. Be careful not to change :> :> :# the 'exec tail' line above. :> :> :menuentry 'OpenBSD 7.8' { :> :> : chainloader (hd0,gpt1)/BOOTX64.EFI :> :> :} :> :> : :> :> :and run /sbin/update-grub. :> :> : :> :> :Your next boot should have a Grub menu entry for OpenBSD 7.8. :> :> : :> :> :Fedora/RedHat uses a conflicting /boot/efi/BOOTX64.EFI :> :> : :> :> :I'll work with the FAQ maintainers to correct. :> :> : :> :> : :> :> :-- :> :> :J. Scott Heppler :> :> :
