So I'm tackling an ambition project (to me, anyway). I have 4 3TB drives and a server I'm building. The goal is to have a single Raid 10 (6TB) system for my new server.

I have a UEFI motherboard (ASRock Z77), and I was able to set up the raid (using mdraid, I set up a single "5.46 TiB" drive) with GPT as the basis for each 3TB drive, but the install and boot isn't working. I've found a lot of outdated information on installing and booting to GPT, but nothing seems to work. I tried building a small partition for /boot and for the grub install as fat32 partitions. With grub installing to a 1MiB partition, I got grub (non UEFI ... grub on the UEFI boot doesn't seem to install) to install and even find the linux installation, but then it doesn't boot. Nothing showed up in the dmesg log or anywher else I knew to look, so I'm sure it never actually hit the file system.

I know I can give up on GPT as the main partition and install Ubuntu (or whatever) to a simple ext4 non-raided partition, then load GPT on everything else. Sure. But I'd like to figure this out and not have separate drives sitting out there.

I'm guessing, but don't know, that there's some magic in how I need to partition the system and then some more magic in how it needs to be installed. I'm ok with blowing away the raid and starting over (even though it takes 8 hours), but I'd really like to get the max size on this raid.

Any help would be appreciated at this point.

Hi:JohnLocke

Are those 4 3TB drives external or did you install them inside of your computer tower?

I am pretty sure that the OS 'journaling EXT 4 filesystem' and 'swap' has to be on the drive that you want to use.
It sounds by your description that the 5.46 ToB is a seperate drive and you formatted it with GPT but somehow I don't think that communicates to the other 3 drives. (I don't have RAID experience)

If you want to you can also use one or more of those drives for storage-
http://pysdm.sourceforge.net/

With the newer motherboards that have UEFI BIOS only the Linux distro's with a key will install.
I found this out the hard way by building my own computer a few weeks ago.
Ubuntu 12.04 distributions and Fedora will work on a mobo that has UEFI BIOS-
http://linux.slashdot.org/story/12/0...i-restrictions

If you have another operating system on the HDD or TB Drive that you are installing Ubuntu on than you will have to shrink that OS's partition
if you want to dual boot with it and Linux.

To veiw all partitions on your machine as 'root'Run:

No ... those four drives are internal drives and the 5.46TB is the raided combination of those drives. I got this working (to some extent) by making a separate vfat partition on one of the drives before raiding them which I used as the EFI boot drive. The running OS is on the GPT raided partition (~5.5 TB).

I still don't know if I need the separate grub partition I made (both the EFI and grub partitions are < 50MB) and I put a 1GB swap partition on each drive (those are non-raided) that I'll set to equal priority.

I need to do some more experimenting still to find /exactly/ the right combinations and sizes needed of these partitions, but it at least "works" with this combination.

I did have to use the new "boot-repair" program to fix the EFI boot partition after installation ... auto-install of Ubuntu 13.04 didn't work to install the bootloader into grub nicely on a GPT partition (or on the other partitions available).

I am not sure if you need a separate grub partition or not-
Generally the GNU GRUB MENU can hold up to 3 operating systems on one HDD-

Perhaps the Grub Manual: PDF will prove as useful and help you to find out if you should or shouldn't create another grub paritition:-

http://www.gnu.org/software/grub/manual/grub.pdf