Hello, The issue is fixed. But I cannot really gives a recipes. The issue was in the generation of the grub.cfg 1) It did let boot on system 1 when generated by system 2 (it looks that a efilinux and efiinitrd were missing). This let me boot on system 1. 2) When I booted on system 1, the new grub.cfg yjay generated did not let me boot on system 2. However, after I did it again and gain, it finally generated a correct file which let me boot both systems. I noted that the structure of the grub.cfg files generated differ according to with system generates it. I also noted that sometimes, some partitions which were not mounted because there were not in the fstab, could never be mounted: busy! A rebooting solves the issue! > > On Tue, 25 Jun 2019 21:59:27 +0200 > "Patrick Dupre" <pdupre@xxxxxxx> wrote: > > > Hello, > > > > Thank for your suggestions. > > Here is the current situation. > > After I installed the 2nd boot system on sda6 with a /boo/efi on the > > sdb1 (the 2 systems could mount the same /boot/efi), I have never > > been able to boot on the original system. > > This accords with my understanding: there is no chainloading of efi > systems. A single /boot/efi boots a single OS instance. > > > I have a grub2-mkconfig to generate a grub.cfg which has never work > > properly to boot the 1st OS (which has originally installed in fedora > > 28, actually, I noted large differences between the fedora 28 and > > fedora 30 grub.cfg files). Then, I made a grub2-install -o /dev/sda. > > This created a "mess", I only got a grub shell. > > Fortunately, I have a mbr saved for sda and I reinstalled the default > > mbr, and I also had a /boot/efi saved. Hence, I reinstalled the old > > /boot/efi. > > So, you updated a bios F28 to efi F30? I don't know how well that is > supported, but it sounds like a recipe for trouble. > > > Lucky, I was able to boot on my "old" system. > > I booted 2 times and then I run > > grub2-mkconfig /boot/efi/fedora/grub.cfg because I wanted to be able > > to have the option of booting of 2 systems. But, then, no way to > > reboot, any of the systems. I tried tons of times from the bios > > configuration. No way. I tried to boot by using the "old" (the one > > which has working for the last boot) grub.cfg, and the new one, but > > same result. In the best situation, I could read something like: > > error file /EFI/x64_86-efi/increment.mod not incremented. > > (it was fast that it was hard to read). > > > > I do not understand, because I have 2 other machines with 2 or 3 > > boots (with 1 or 3 disks, one in efi and one is legacy) in fedora 30 > > and I cannot complain. > > But on those other systems are you trying to boot a second efi OS from > the first /boot/efi system? On my efi install, when I run > grub2-mkconfig, it finds all the bios installations and creates menu > entries for them, so I can boot them from the efi system. > > I will be installing a second efi system on a different disk, so I will > be able to test how this works with two efi systems in a setup similar > to yours. I just don't think I will be able to boot the second efi > install from the first, and vice versa. > > > I just see one difference for this one: it has 2 disks, > > the ssd in mounted in sdb (with the /boot/efi in sdb1) with one > > system on sdb, and the second (new) system in sda (sda6). > > I just do not understand why it is so much a problem. > > Now, what to do? > > It seems that I am stuck with the bios! > > options > > 1) destroy the sda6? and try to boot !!! > > 2) boot on the stick and make a chroot? > > and fix what has to be fixed? But I have no idea. > > 3) Reinstall the sda6, but then how to have the 2 systems running? > > Why I would be more successful the 2nd time? > > 4) Other options? > > I think you should create the EFI partitions on /dev/sda, EF00 (2MB), > EF01 (2MB), EF02 (1GB), and then reinstall the OS on /dev/sda putting > the /boot/efi in the newly created EF02 partition on /dev/sda. That > will get you a working efi install of F30. From there you can clean up > the F28-F30 upgrade to ensure that it too can boot efi. But I don't > think you can expect to boot either of the efi installs from the > other. You will have to select the non-default efi install from the > firmware boot menu. > _______________________________________________ > users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx > To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx > Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ > List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines > List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx > _______________________________________________ users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx