O problema é exatamente como descrito aqui . De acordo com a resposta do local do grub de thread, deve ser alterado de /dev/md126p1 para /dev/md126 . O que eu não entendo é como fazê-lo durante o processo de instalação.
O sistema é o Ubuntu Server 16.04.1 LTS.
# lsblk -o name,mountpoint,label,size,fstype
NAME MOUNTPOINT LABEL SIZE FSTYPE
sda 931.5G
├─sda1 oblsud:0 487M linux_raid_member
│ └─md0 /boot 972M ext4
├─sda2 1K
├─sda5 oblsud:1 11.2G linux_raid_member
│ └─md1 [SWAP] 22.3G swap
├─sda6 oblsud:2 93.1G linux_raid_member
│ └─md2 186.1G LVM2_member
│ └─system-rootfs / 186.1G ext4
└─sda7 oblsud:3 826.7G linux_raid_member
└─md3 1.6T LVM2_member
└─storage-home /home 1.6T ext4
sdb 931.5G
├─sdb1 oblsud:0 487M linux_raid_member
│ └─md0 /boot 972M ext4
├─sdb2 1K
├─sdb5 oblsud:1 11.2G linux_raid_member
│ └─md1 [SWAP] 22.3G swap
├─sdb6 oblsud:2 93.1G linux_raid_member
│ └─md2 186.1G LVM2_member
│ └─system-rootfs / 186.1G ext4
└─sdb7 oblsud:3 826.7G linux_raid_member
└─md3 1.6T LVM2_member
└─storage-home /home 1.6T ext4
sdc 931.5G
├─sdc1 oblsud:0 487M linux_raid_member
│ └─md0 /boot 972M ext4
├─sdc2 1K
├─sdc5 oblsud:1 11.2G linux_raid_member
│ └─md1 [SWAP] 22.3G swap
├─sdc6 oblsud:2 93.1G linux_raid_member
│ └─md2 186.1G LVM2_member
│ └─system-rootfs / 186.1G ext4
└─sdc7 oblsud:3 826.7G linux_raid_member
└─md3 1.6T LVM2_member
└─storage-home /home 1.6T ext4
sdd 931.5G
├─sdd1 oblsud:0 487M linux_raid_member
│ └─md0 /boot 972M ext4
├─sdd2 1K
├─sdd5 oblsud:1 11.2G linux_raid_member
│ └─md1 [SWAP] 22.3G swap
├─sdd6 oblsud:2 93.1G linux_raid_member
│ └─md2 186.1G LVM2_member
│ └─system-rootfs / 186.1G ext4
└─sdd7 oblsud:3 826.7G linux_raid_member
└─md3 1.6T LVM2_member
└─storage-home /home 1.6T ext4
sr0 1024M
# parted -l
Model: ATA WDC WD10EZEX-60M (scsi)
Disk /dev/sda: 1000GB
Sector size (logical/physical): 512B/4096B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
1 1049kB 512MB 511MB primary boot, raid
2 513MB 1000GB 1000GB extended
5 513MB 12.5GB 12.0GB logical linux-swap(v1) raid
6 12.5GB 113GB 100GB logical raid
7 113GB 1000GB 888GB logical raid
Model: ATA WDC WD10EZEX-60M (scsi)
Disk /dev/sdb: 1000GB
Sector size (logical/physical): 512B/4096B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
1 1049kB 512MB 511MB primary boot, raid
2 513MB 1000GB 1000GB extended
5 513MB 12.5GB 12.0GB logical linux-swap(v1) raid
6 12.5GB 113GB 100GB logical raid
7 113GB 1000GB 888GB logical raid
Model: ATA WDC WD10EZEX-60M (scsi)
Disk /dev/sdc: 1000GB
Sector size (logical/physical): 512B/4096B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
1 1049kB 512MB 511MB primary boot, raid
2 513MB 1000GB 1000GB extended
5 513MB 12.5GB 12.0GB logical linux-swap(v1) raid
6 12.5GB 113GB 100GB logical raid
7 113GB 1000GB 888GB logical raid
Model: ATA WDC WD10EZEX-60M (scsi)
Disk /dev/sdd: 1000GB
Sector size (logical/physical): 512B/4096B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
1 1049kB 512MB 511MB primary boot, raid
2 513MB 1000GB 1000GB extended
5 513MB 12.5GB 12.0GB logical linux-swap(v1) raid
6 12.5GB 113GB 100GB logical raid
7 113GB 1000GB 888GB logical raid
Model: Linux device-mapper (linear) (dm)
Disk /dev/mapper/storage-home: 1775GB
Sector size (logical/physical): 512B/4096B
Partition Table: loop
Disk Flags:
Number Start End Size File system Flags
1 0.00B 1775GB 1775GB ext4
Model: Linux device-mapper (linear) (dm)
Disk /dev/mapper/system-rootfs: 200GB
Sector size (logical/physical): 512B/4096B
Partition Table: loop
Disk Flags:
Number Start End Size File system Flags
1 0.00B 200GB 200GB ext4
Model: Linux Software RAID Array (md)
Disk /dev/md0: 1019MB
Sector size (logical/physical): 512B/4096B
Partition Table: loop
Disk Flags:
Number Start End Size File system Flags
1 0.00B 1019MB 1019MB ext4
Model: Linux Software RAID Array (md)
Disk /dev/md1: 24.0GB
Sector size (logical/physical): 512B/4096B
Partition Table: loop
Disk Flags:
Number Start End Size File system Flags
1 0.00B 24.0GB 24.0GB linux-swap(v1)
Error: /dev/md2: unrecognised disk label
Model: Linux Software RAID Array (md)
Disk /dev/md2: 200GB
Sector size (logical/physical): 512B/4096B
Partition Table: unknown
Disk Flags:
Error: /dev/md3: unrecognised disk label
Model: Linux Software RAID Array (md)
Disk /dev/md3: 1775GB
Sector size (logical/physical): 512B/4096B
Partition Table: unknown
Disk Flags: