Pascal, Thank you for the informative response. I would like to assure I address your concerns it this recovery. > (...) > > System description: > > amd64 with a HDD and 3 pairs of SSDs. The SSD are set up as RAID0 in > > pairs. The HDD currently hosts Debian 8. I used this to configure the > > SSDs to overlay the RAID0s with an LVM. The RAIDs were built on a > > second partition of each SSD. The first partition is 1G for potential > > boot use. AMD64 32G RAM sda, sdb 32GB + 32GB, RAID0 - md0, LVM, GParted shows 1MB reserved, 1 GB (EFI) sdc, sdd 64GB + 64GB, RAID0- md1, md127, LVM, GParted shows 1MB reserved, 1 GB (EFI) sde, sdf 120GB + 120GB, RAID0- md0, md126 LVM, GParted shows 1MB reserved, 1 GB (EFI) sdg, sdh are 2 and 4 GB HD, sdg currently hosts debian8.+q++q md0-2 form a vg for the new debian8 as dom0 for a xen instance, md127 is a vg, md126 is a vg. md127 & 126 are for swap files.
> > LVM on multiple RAID0 ? You don't care much about reliability, do you ? > Lose a single disk and you may lose all your LVM. Yes, there is risk. This is a personal workstation and will be backed up regularly and doesn't need to be up all the time. I have lost motherboards more often the disks, and I have never lost a ssd. I chose Linux RAID over motherboard RAID due to this. > > I use a USB stick to load the second Debian. 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. > > I assume the architecture is i386 or amd64. amd64 > > If /boot is on LVM and you choose GRUB as the bootloader in BIOS/legacy > mode (grub-pc), you must select a whole disk. > > If the disk has an MSDOS partition table, it should have enough > unallocated space before the first partition ; modern partition > management tools including the Debian installer will leave ~1 MB > unallocated space by default, which is enough. > > If the disk has a GPT partition table, it should contain a small > unformatted partition of type "BIOS boot" or "bios_grub" ; again, 1 MB > is enough. If the disk is larger than 2 TiB, the BIOS boot partition > should be located within the 2 TiB boundary so that it can be accessed > through the BIOS disk functions. > gdisk reports that the sda and sdb have gpt partitions. > The unallocated space or BIOS boot partition is required to install the > GRUB's core image which can be booted by the GRUB's boot image installed > in the MBR of the disk. The core image will include modules to be able > to read RAID and LVM volumes in order to access other required boot > files located in /boot. Otherwise, GRUB's core image will be installed > in /boot/grub and retrieved by GRUB's boot image using block lists ; > however this is less reliable because blocks may be moved around by LVM > or the filesystem. I have attempted again to install a new debian8 on the LVM on RAID0 for sda&b. I learned more about using the installer for portioning so I was able to get /boot on a RAID0 partition (outside of the vg). On rebooting, nothing would boot. The screen message said to insert the media to boot from. Now I get to recover what ever I lost. I have not figured out how to do that. Any help would be appreciated.
