Changes

Sahil and I tried to configure RAID 10 using the software RAID option in the installer, which is documented [https://help.ubuntu.com/community/Installation/SoftwareRAID#Partitioning_the_disk here]. We put two 64 GB swap space partitions on the first two hard drives, and created two ext4 partitions that took up the rest of the space on those two drives. For the other two drives, we used a single ext4 partition for each drive. For all of the ext4 partitions, we set the bootable flag to "on." Then we chose to configure the software RAID, created a new MD device, and chose RAID10 with 2 active devices and 2 spare devices. For the active devices, we chose the two ext4 partitions on the first two hard drives, and for the spare devices, we chose the two ext4 partitions on the other two hard drives. But then the installation process fails when the GRUB boot loader can't be installed, because the GUID partition tables (GPT) need a designated, small (1 MB is enough) partition for the GRUB bootloader.

I guessed that, because the 1 MB RAID device was made first, that the kernel tried to install itself to that device and failed. So I went back to the partitioner and set the first RAID device to "do not use" and then tried the installation process again. It prompted me a couple of times warning me that the old filesystem would be overwritten, but I continued the installation regardless. But then the GRUB boot loader failed, even if we tried not installing it to the master boot record (MBR) and installing it to "dev/md0" or installing it to "dev/md0_raid1"