Ubuntu 22.04桌面版安装时RAID 6阵列加密配置疑问

Hey there! Let me walk you through exactly when and how to encrypt your RAID 6 array during a fresh Ubuntu 22.04 Desktop installation—since the default installer doesn’t make this super obvious, we’ll need to take a quick detour into the live environment first:

Step-by-Step Breakdown #

• Start by choosing "Try Ubuntu" instead of "Install Ubuntu" when you boot from the installation media. The desktop installer’s built-in tools don’t support creating encrypted RAID directly, so we’ll set up the RAID and encryption manually first.
• Open a terminal (press Ctrl+Alt+T), then install the required tools with this command:

  sudo apt update && sudo apt install mdadm cryptsetup
  

• Run lsblk to list all your drives and confirm the device names for the disks you want to use in the RAID 6 (e.g., /dev/sdb, /dev/sdc, /dev/sdd—double-check you don’t pick your SSDs for root/boot!).
• Create the RAID 6 array. Replace X with the number of disks you’re using (minimum 3) and the /dev/sd* entries with your actual disk names:

  sudo mdadm --create /dev/md0 --level=6 --raid-devices=X /dev/sdb /dev/sdc /dev/sdd
  

• Now encrypt the RAID array. You’ll be prompted to set a strong password—don’t lose this, as it’s the only way to recover your data later:

  sudo cryptsetup luksFormat /dev/md0
  

• Unlock the encrypted RAID device (we’ll use encrypted_raid as an alias here, but you can name it anything):

  sudo cryptsetup luksOpen /dev/md0 encrypted_raid
  

• Format the unlocked encrypted device with a filesystem like ext4:

  sudo mkfs.ext4 /dev/mapper/encrypted_raid
  

• Launch the Ubuntu installer from the live desktop. When you get to the partitioning step, select "Something else" (manual partitioning).
• Set up your two SSDs for /boot and / (root) as you planned. Then locate /dev/mapper/encrypted_raid and assign it a mount point (like /data, or whatever makes sense for your use case).
• Finish the installation as normal. The installer will automatically add the necessary entries to /etc/fstab and /etc/crypttab, so after rebooting you’ll just need to enter your encryption password to unlock the RAID 6 array.

Quick Notes #

• Double-check your disk names before running any commands—you don’t want to accidentally wipe your SSDs!
• Store your encryption password somewhere safe. If you lose it, there’s no way to retrieve the data on the RAID array.
• If you want automatic unlocking (not recommended for desktop setups, since it reduces security), you can set up a key file, but manual password entry is the safer default.

备注：内容来源于stack exchange，提问作者hank744