Grub-install failure...

[Robert Heller]

Grub-install is failing:

sauron% sudo grub-install /dev/sda
[sudo] password for heller: 
Installing for i386-pc platform.
grub-install: warning: this GPT partition label contains no BIOS Boot Partition; embedding won't be possible.
grub-install: error: embedding is not possible, but this is required for RAID and LVM install.
sauron% sudo parted /dev/sda print
Model: ATA Hitachi HUA72202 (scsi)
Disk /dev/sda: 2000GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags: 

Number  Start   End     Size    File system  Name     Flags
 1      1049kB  256MB   255MB                primary  msftdata
 2      256MB   1295MB  1039MB  ext3         primary  msftdata
 3      1295MB  2000GB  1999GB               primary  msftdata

sauron% cat /proc/mdstat 
Personalities : [raid1] [linear] [multipath] [raid0] [raid6] [raid5] [raid4] [raid10] 
md1 : active raid1 sdb3[0] sda3[1]
      1952118784 blocks super 1.2 [2/2] [UU]
      bitmap: 1/15 pages [4KB], 65536KB chunk

md126 : active raid1 sdb2[0] sda2[1]
      1003904 blocks [2/2] [UU]
      
unused devices: <none>
sauron% 

What am I missing? Grub 1 is happy and I can boot that way, but it is
presently defaulting to CentOS 6.10. I am at this point ready to install grub
2 and make the default boot to be Ubuntu 18.04, but grub 2's installer is
complaining... My motherboard's BIOS is an older one (not UEFI). When I
installed these 2TB disks, I set asside a UEFI partition (part 1 on /dev/sda
and /dev/sdb), but I am presently not using it -- I anticipate getting a new
motherboard, which will likely have a UEFI boot prom.

/dev/sd[ab]2 is a mirror RAID (metadata 0.93) and is the /boot file system, 
/dev/sd[ab]3 is a mirror RAID (metadata 1.2) and is a LVM volume group.



-- 
Robert Heller             -- 978-544-6933
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