My setup

  • 2x 512GB SSDs - GPT Partition
  • Legacy boot

ssd layout(on each disk):

  • 4MB: space reserved for bios grub(not part of RAID0 array)
  • 16GB: swap - reserved for RAID volume
  • 25GB : mnt / - ext4 - reserved for RAID volume
  • ~420GB: mnt /home - ext4 - reserved for RAID volume

The error I eventually receive is "executing 'grub-install /dev/md1 failed"

I continued installation without bootloader thinking I will install grub by live-usb.

From the live-usb,

I ran sudo grub-install /dev/nvme01n1(name of ssd). The error I receive is - grub-install failed to get canonical path of aufs'.

I tried mount /dev/nvme01n1p3 /mnt (the / of the RAID array), the error I receive is unknown file-system linux_raid_member'

mdadm does not detect any RAID disks ..

(I am following parts of the Software RAID tutorial. I plan to install desktop-ubuntu from within the server after installation, as shown in this video)

Other routes that I tried:

  • I tried adding the bios_grub reserved space to the RAID array but that resulted in an error during the formatting step.

  • The disks initially had a msdos partition but I got the same bootloader error and I could not figure out how to allocate space for grub in msdos disks. After reading online, it seemed like booting from a GPT disk could be a solution and I changed the partition to GPT ..

This is taking especially long as I have started reading about MBR/GPT, BIOS/UEFI only when I began this install ..

Please let me know how I should proceed.


I ran Boot repair from within the live-usb and it prompted me to remove dmraid as it would conflict with mdraid.

On doing so, I was able to run mdraid --assemble --scan and view my RAID0 disks.

Boot-repair eventually detected GPT partition and asked me to make a bios_grub, unformatted partition at beginning of disk. I was not sure how to proceed now as I already had the necessary partitions.

I then followed this section of Grub2 installation. Grub was installed and I could login at tty1.

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