I installed, just to try it out, openSUSE Tumbleweed KDE 20250625 on the same internal drive (SSD) where Fedora 42 was already installed.
When I reboot now, I do not have the choice between the two, but openSUSE Tumbleweed starts always immediately.
What to do to have the opportunity to use both OS (not at the same time !) ?
Do I have to uninstall openSUSE and install it on a external drive or … ? And how ?
Please, if you see a possibility to solve my problem, present the solution step-by-step : I am not an expert !
Anyway, thanks in advance for your reply.
Best regards.
Hi @lukvdl
If I remember correctly you should enter yast in the partitioning section. From there look for os-prober and the various settings (how to increase the selection time in grub).
Hi
This is actually against the UEFI standard and may not work with all implementations, as there is an expectation of one EFI system partition per drive
@lukvdl
What you are trying to do is generally possible. You should have just one EFI partition, but you can provide custom grub.cfg entries to load the kernel and initrd of the other distribution from a different /boot partition. However, since you mention being somewhat inexperienced, I would not recommend pursuing this approach. Instead, I suggest sticking with one distribution for the time being, or installing them on different hard drives if you absolutely want to have both. Alternatively, you could run one of them in a virtual machine or use Distrobox.
The setup you are trying to achieve is quite uncommon and likely to be fragile. It may break with every update, leading to a frustrating experience.
Besides, SUSE and Fedora gets their respective subdirectory in the ESP so they can happily live in the same ESP without conflicting each other. You can still use the UEFI boot menu to select between Fedora and SUSE, and that is what I would be doing.
If you really want to use grub for multiboot, change the boot order to Fedora first, and when booted into Fedora, run grub2-mkconfig -o /boot/grub2/grub.cfg. Don’t expect that secure boot would work in this case as the Fedora shim doesn’t have the security key for SUSE unless you enroll it into the mok.
For over a decade, I have installed multiple distros, usually different versions of Fedora, while providing a unique UEFI partition for each on the same SSD and have NEVER experienced a problem where actions such as installation or updating of one distro interfered with another one. My custom is to use gparted to create, format and name those partitions BEFORE performing an install where I select “Custom” and “Standard Partition”.
SSDs used in this manner include M.2 NVME (on the motherboard, on a PCIe adapter card and in an external USB enclosure). This practice is very useful in cases where software is installed and later removed but removing residual residue is more tedious than restoring both the associated UEFI and OS partitions from the last regularly created archives.
Software installation may choose to create and locate an ESP on each target OS boot disk, or may choose to create a
single ESP independent of the location of OS boot disks and OS partitions.
This is the relevant part from the UEFI specification: I understand it to mean one ESP per boot disk.
I decided to stop this topic.
I have the impression that there is no easy solution for my problem or I do not fully understand your answers (I am 78 years old !).
I will now re-install Fedora 42 on my SSD as the only OS, so I will not use anymore openSUSE Tumbleweed.
