RAID woes, can't repartition my hard drives

[darkod]

It shouldn't be a problem, but just for future reference, you shouldn't have formatted the partitions as ext4. That's why I prefer making partitions for raid with parted, and not Gparted. Because parted always creates partitions without any filesystem. You format them yourself later.

For mdadm, you don't format the partitions as ext4. You leave them without any filesystem. After you create the md devices, you format the md devices as ext4 and use them. Not the physical partitions.

[ladasky]

It shouldn't be a problem, but just for future reference, you shouldn't have formatted the partitions as ext4. That's why I prefer making partitions for raid with parted, and not Gparted. Because parted always creates partitions without any filesystem. You format them yourself later.

GParted, at least the version that came with the 13.04 installation, has what looked like a new feature to me: the option to create a partition, but not format it. That's what you told me to do for the little boot partitions and, as you can see, it worked.

For mdadm, you don't format the partitions as ext4. You leave them without any filesystem. After you create the md devices, you format the md devices as ext4 and use them. Not the physical partitions.

[Smacks forehead] Of course! That's also what I did when I built my RAID1 using the text-based interface on the old "alternate install" disks. When you don't do an arcane task for a full year -- you can forget the details.

Now -- did this premature formatting block somehow my grub-install, or didn't it? It would be strange if it did. As you can see, both /dev/sda1 and /dev/sdb1, the partitions intended for Grub, were unformatted.

If you look at the other thread, you'll see that I've decided to go with LVM, given that the Ubuntu installer promotes it. I will now investigate LVM mirroring.

EDIT: Darn it, I started that investigation, and wouldn't you know it -- here's you, Darkod, recommending installing LVM on top of an mdadm-administered RAID!

[darkod]

It shouldn't affect the grub2 install since the small partitions are correct. Maybe a glitch or a bug. You can also try adding grub2 later. If the whole system installed fine, just adding grub2 is easy.