Public bug reported: I opened a forum ticket about this observation here:
"Unable to boot from HDD 20.04 installed with BIOS in Legacy mode" https://ubuntuforums.org/showthread.php?t=2455005&p=14015093 I suspect there might be a defect in Ubuntu Server 20.04 ISO. I was loading it onto a ThinkPad to test out the new Ubuntu Server LTS release. I had the ThinkPad BIOS set to boot from legacy mode disks, all UEFI disabled. The partitions Ubuntu Server 20.04 created for me were as follows: Disklabel Type: gpt sda1 BIOS Boot sda2 Linux filesystem (which I selected xfs) The system failed to boot from the HDD. When trying to boot from the system's HDD, I only am able to get the ThinkPad "Boot Menu / Application Menu" screen to come up. Selecting ATA HDD0 loops back around to the same menu. It was suggested that Ubuntu 20.04 really prefers to boot from drives in UEFI mode. I changes the BIOS settings, wiped the disk during another test installation. This time the partitions the installer created were as follows: Disklabel Type: gpt sda1 EFI System sda2 Linux filesystem (which I selected xfs) And the system does boot from the HDD now. So is this a defect in the installer for Ubuntu Server 20.04 that it does not produce a bootable drive when the computer BIOS is set to legacy boot mode? I was expecting to see the legacy boot partition table type not be a gpt partition table. Might that have something to do with the failure to boot? I think the fact that for the legacy boot installation, Ubuntu Server did at least create a first partition of type "BIOS boot". <><><><> I tried the same installation on the same ThinkPad from the ubuntu-20.04.1-live-server-amd64.iso disk. Same results as before. Looks like Ubuntu Server has a defect booting from disks where the BIOS is set to legacy mode. This is not broken in Xubuntu 20.04 installation. Logging an Ubuntu Server installer defect. <><><><> Xubuntu 20.04 does NOT have this same defect. Xubuntu 20.04 boots properly when installed to systems with the BIOS set to legacy mode for the hard drive access setting. ** Affects: ubiquity (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1912276 Title: Ubuntu Server 20.04 installation to drive with BIOS set to legacy mode results in non-booting drive To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubiquity/+bug/1912276/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs