On Tuesday, September 8, 2015 at 5:40:04 AM UTC-5, Pascal Hambourg wrote: > ray a écrit : > > On Monday, September 7, 2015 at 3:40:05 AM UTC-5, Pascal Hambourg wrote: > >> > >> Did the Debian installer boot in EFI or BIOS/legacy mode ? > > > > The motherboard BIOS reports the Debian installation media as a UEFI USB. > > The installer boot screen says UEFI and it is the same media used on the > > harddisk. > > Then could you clarify the following parts in your first post : > ============================ > > I use a USB stick to load the second Debian. > > What do you mean by "to load" ? To /install/ the second Debian system on > the SSDs or to /boot/ it once installed ?
Yes, that was a poor choice of words (to load). I installed the secod Debian via the USB stick. > > > I have a lVM partition for the new installation. When I select it, the > > installer (in manual mode) says it is not bootable and go back to setup > > to correct. When I go back to setup, I don't see any way to do anything > > but select a VG, dm, sdx, or HDD. > > In which part of the installer is this happenning ? During installation, this is 'partition' in manual. > I first thought you were talking about the boot device selection during > the boot loader installation, but in UEFI mode the installer does not > prompt about a boot device because there is no boot device. The > bootloader is installed in an EFI system partition which should be > formatted as FAT16 or FAT32 and mounted on /boot/efi (implicit if you > select "use as EFI system partition). > ============================ > > > I had a Debian instance on the HD that worked fine and when I > > installed a new instance on the SSD, neither would boot. > > > > So I rebuilt the HD instance, ran it to configure the SSDs, and again, > > when installing to the SSDs, nothing will boot. > > This is where things go awkward with GRUB UEFI. UEFI boot is intended to > make multiboot easier. This is quite true with different operating > systems (e.g. Windows + Linux, or Debian + Ubuntu). Each system is > supposed to install its own boot loader in a separate directory in the > EFI boot partition and register it as an EFI boot entry with a fancy > name so that it can be selected at boot time, either implicitly using > priorities or manually through a boot menu displayed by the firmware. That is an eye-opener. > > However it does not work this way if you install two copies of a Debian > system with GRUB : the latter installation will overwrite and replace > the former boot loader with its own, because the Debian installer always > uses the same name "debian" for the directory in the EFI system > partition and the EFI boot entry. > > If you intend to keep the hard disk containing the Debian system > installed, you don't need to install another boot loader for the Debian > system on the SSDs. The GRUB boot loader on the hard disk can boot > another instance of Debian after detecting it with os-prober and > rebuilding a new menu with update-grub to include it. How does os-prober get initiated? I ask this as it seems to use this method, I will boot up into the HDD instance, then boot into the SSD. Can I rename the HDD boot loader before installing the second instance? And if so, how?
