Choose Configure the Logical Volume Manager. Because we haven’t written the changes made to RAID 1 array yet, we’ll be asked to save these changes. Choose yes, then choose Create Volume Group. Give volume group some name, for example vg1, then select /dev/md1 device for volume group and choose continue.

Next, select Create logical volume, accept vg1 as volume group and give a name to volume. I named it swap. Enter whatever size you’ll want for swap volume and press enter. After swap volume is created, we’ll create the root volume. So select Create logical volume again, accept vg1, name it root and accept the default size (entire remaining space). After we’re done, choose Finish.

Now we must partition and initialize the new logical volumes. Select the swap volume, press enter. Set it to use as swap area and then select Done setting up the partition.

Select the root volume, set it to use as Ext4 file system, set it’s mount point to / and select Done setting up the partition. After this we should have this configuration set:

Now choose Finish partitioning and write changes to disk.

When asked if you want to boot if raid becomes degraded, choose yes

Now, continue with ubuntu installation as normal.

Edit: Already installed it on physical machine, and couldn’t get it working with AHCI, so I had to tweak bios settings to have SATA in IDE mode.

It looks like isn’t possible to install a boot partition on RAID 5, so for boot I’ll use RAID 1 (mirror).

First grab a copy of alternate installation cd for your platform. Setup the virtual machine and let’s go. Proceed with the installation until you get to the “Partition disks” screen. Press alt+F2 to switch console and as prompted press enter to activate console.

For each of the three disks, create 2 partitions. The first on will be used in a RAID 1 for boot and the second will be used in RAID 5. Set both partition type to fd (Linux raid autodetect).

Repeat the same exact steps above for /dev/sdb and /dev/sdc (second and third disks). When finished, it’s time to create the RAIS arrays.

After a few minutes, check if everything went ok and both arrays are active. If the RAID 5 array is still in recovery, wait a few more minutes.

Ok. First step is done. Go back to install screen with alt+F1. Now we must go back to Detect disks phase, so press Tab to select <Go back> and press Enter. Choose Detect disks and press enter.

If everything went ok, the following screen should appear. Select first array and press enter.

Configure the partition using Ext3 journaling file system, /boot as mount point and choose Done setting up the partition.

On part 2, we’ll be setting up LVM and finishing ubuntu installation.