Re: How to Boot with LVM
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 ?
> 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 ?
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.
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.