Install Ubuntu 20.04 Focal Fossa with RAID 1 on two devices

As I stumbled on the same issue and found out that the actual docs haven't yet been updated for the new storage configurator (as of early June 2020), here's what I did to get a working softRAID 1 setup with 2 disks on the Ubuntu Server edition:

  • Select "Custom storage layout" when you reach the storage configuration step of the installer.
  • If the disks have existing partitions, click on each disk under AVAILABLE DEVICES and then select REFORMAT. This will (temporarily) wipe out the partitions.
  • Now select the 1st disk to add as book disk (same menu that had REFORMAT in).
  • Do the same with the 2nd disk
  • You will see 2 1.000M bios_grup partitions created under USED DEVICES.
  • The trick to setup a softRAID array is to create partitions for /boot, swap and / on each disk, but WITHOUT formatting them (an as such, there won't be a mount point for now).
  • So go ahead and "Add GPT Partition" on the 1st disk, give it a 1G size and choose to leave it unformatted. Do the same for the 2nd disk. These will be the /boot partitions for the softRAID array. Under each disk on AVAILABLE DEVICES you will now see "partition 2".
  • Now we'll prepare the swap partitions. "Add GPT Partition" on the 1st disk, give it the same or half the size of your RAM (e.g. let's say 16G cause we have 16G of actual RAM) and choose to leave it unformatted. Do the same for the 2nd disk. Under each disk on AVAILABLE DEVICES you will now see "partition 3".
  • Now we'll prepare the / partitions. "Add GPT Partition" on the 1st disk, do not set a size (so it uses all available) and choose to leave it unformatted as with all others you did so far. Do the same for the 2nd disk. Under each disk on AVAILABLE DEVICES you will now see "partition 4".
  • Now click on "Create software RAID (md)" under AVAILABLE DEVICES. We'll create the first softRAID partition (md0) by selecting the two "partition 2" entries (one from each disk). Click "Save".
  • Repeat the process for md1 and select the two "partition 3" entries. Hit "Save".
  • Repeat the process for md2 and select the two "partition 4" entries. Hit "Save".
  • We now have 3 pairs of AVAILABLE DEVICES which will now format as the actual softRAID partitions. So select md0 and then "Add GPT Partition", format as EXT4 and mount on /boot.
  • Select md1 and then "Add GPT Partition", format as SWAP.
  • Select md2 and then "Add GPT Partition", format as EXT4 and mount on /.
  • All these mdX softRAID partitions will now appear under USED DEVICES and you are ready to proceed with Ubuntu's installation.
  • At the very bottom, you should now see "Done" enabled so hit it and proceed.

Enjoy :)

(Also referenced on: https://gist.io/@fevangelou/2f7aa0d9b5cb42d783302727665bf80a)


I fixed it in this way.

Solution 1: Install RAID 1 without encrypt your disks

First, I have prepared both the hard drives (SSD in my case) using "GParted Live" (I created a bootable USB with the GParted ISO):

  1. 512 MB partition, named "/bios/efi", fat32, flagged as "boot, esp";
  2. 10 GB partition, named "/", ext4, flagged as "raid";
  3. (Entire remaining space) /home partition, named "/home", ext4, flagged as "raid";

I decided to omit a "/swap" partition because I have 16 GB of RAM installed, and I use SSD drives, and this server will be just a little home NAS, so I don't need high performance.

Then, using the "Custom storage layout" during the Ubuntu Server 20.04 installation:

  1. I checked both disks to be "added as a boot disk";

  2. Using the "Create software RAID (md)" option, I selected the "/" - root - disk one partition, and the "/" partition of disk two, to create a new "md0" volume (always active);

  3. I created another "RAID md" volume, but this time with "/home" partition (always active), selecting both "/home" partitions to create a new "md1" partition;

  4. I selected the "md0" partition (the root partition created before) and choose "Add GPT Partition", and than I selected format as "Ext4" and mount on "/";

  5. Similarly with "md1" partition (the /home partition), I choose "Add GPT Partition", and than I selected format as "Ext4" and mount on "/home";

  6. After that I choose "done" and I completed the installation.

Solution 2: Install RAID 1 with disks encryption

Here I wrote a quick guide about how I solved. The main problem is related to the "/boot" partition, that can't be inside the encrypted partition, because the grub's encryption it isn't supported yet.

I hope that this guide will be useful for other Ubuntu users.

Tags:

Partitioning

Server

Raid

Mdadm

20.04

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