Problems with inatlling on an existing partition

I have a new laptop with an interanl SSD and Windows installed. i had some maor probems with BIOS settings when trying to install from a Rocky 9 DVD on USB system. I began with simply trying a full disk install, which did produce a bootabe system, however the BIOS (Acer Aspire )seemed to lock me out of using the internal hard disk which meant the install was restricted to the internal SSD, However, there were two non-Rocky related problems - I could not disable the Intel RST disk BIOS software so one disk was not visible to Rocky 9. The BIOS defaults to mapping the F1-F12 keys to functions normally reached with a fn key. My fvwm2 configuration uses function keys heaviy to do tasks like raise/lower/create/resize xterms, so requriing those functions to use an auxialiary key was undesireable, Cutting this story short, the BIOS ocked up to the point where nothing on the BIOS pages could be selected, including choosing the boot device. I sent the laptop in for repair after having it for less than one week. Acer replaced the motherboard and re-installed Windows witout any charge, so outside of lost time things were OK

I decided it might be a good idea to retain a Windows installation and dual boot, I was finding the Rocky install a bit strange, so I instlled a copy of Linux Mint I had lying about. This workedm but it lett me with a system that I didn’t liike (Gnome is well down my list of things I want ever to deal with) and I ound other problems, for example ssh-agent run before starting fvwm no longer passed the auth socket to xterms opened afters starting X, whereas on my previous laptop install of CentOS this worked as expected. I ran a script to do ssh-agent bash, then startx. Every xterm I opened now used the ssh-agent I started before X began.

So, (for those who haven’t fallen asleep by now) I went back to trying to install Rocky 9 on the partition where I had placed Linux Mint. I did not want to have the install reformate the very small boot/EFI partition because I did not want to lose the Windows boot sotware. However, every attempt to let the instller create the mount points within the ex-Mint partiion seems to fai with a message saying that there must be a mount point for /boot/EFI. There is a partion holding the current EFI fiies (Windows and the not yet overwritten ubuntu (actaully Mint) files. I tried going throug the installer’s help text, which is another problem - once I entered those pages there was apparently no wy to exit back to the installer.

What am I supposed to do to preserve the Windows boot manager and allow rocky to add it’s EFI files?

You would have to select the appropriate /boot/efi partition when you are allocating the positions, just like when you selected the ones that Mint was using. You should be able to select it without it formatting it as well. The installer can reuse existing partitions. Since the installer mentioned about this, means that this partition wasn’t selected.

When I tried selecting the existing /boot/efi partition (inherited rom Windows), the installer kept trying to use the following partition nvme0n1p2 and not nvme0n1p1 which was the original /boot/efi partition. This was something I didn’t want to have happen.

What seems to have silence the complaints from the Destination tab of the installer was my having made a 256MB partition, fat32. The installerdid let me select it and mount it eith a mount point from the dropdown list of /boot/efi.

Thanks or you help, I’ve got it booting into Rocky 9 but also capable of booting into Windows if I really want. I’ve still got an entire 1TB ordinary hard disk free for my use

When I install, I do choose option “Customize”. In there I can select the existing /boot/efi filesystem and type into “Mount as” box the “/boot/efi”. There is also the “Reformat” check-box, which you don’t want to select.

The installer would not allow me to select the existing boot.efi partition and then mount it on /boot/efi, with or without ticking the reformat box (I had no intention of carrying on with the install if reformat was enabled, I was simply trying to see i that’s what it wanted). Having a new and unused tiny partition did work and I could install Rocky 9 and boot it or let grub boot Windows, so that’s sort or solved.

I still wonder how you are supposed to exit the help screens and return to the installer, powering off and on seemed a bit drastic. But I won’t be re-installing for a while so it’s not an issue for me

It is curious that you can’t select existing partition; I have never encountered that issue.

ESP (EFI System Partition) is “There can be only one!” – each GPT table can have at most one.
How you manage to get two(?) is even more curious.

One can edit UEFI boot menu entries with efibootmgr and obviously edit /etc/fstab on what is mounted as /boot/efi.

That is a known issue, as in “known on the fora” – can’t recall whether someone reported the bug (to Red Hat).