Set Up Redundant ESP

ESP redundancy might be needed to protect against disk failures and ensure that the system remains bootable even if one boot partition becomes unavailable, increasing overall reliability and uptime.

This guide shows you how to configure an operating system with ESP redundancy. Follow the steps below to create a Trident Host Configuration that configures ESP on a RAID volume.

Goals

By following this guide, you will understand how to configure an ESP on a RAID array.

Instructions

The required configurations should all be made in the Trident Host Configuration. A detailed explanation of creating RAID arrays can be found in the Create a RAID Array guide. For this guide, we break RAID creation into 2 parts:

1. To benefit from redundancy, create a RAID array that utilizes multiple disks by defining 2 partitions for raid1 (esp-1 and esp-2) like this:

   storage:
     disks:
       - id: disk1
         device: /dev/disk/by-path/pci-0000:00:1f.2-ata-2
         partitionTableType: gpt
         partitions:
           - id: esp-1
             type: esp
             size: 1G
       - id: disk2
         device: /dev/disk/by-path/pci-0000:00:1f.2-ata-3
         partitionTableType: gpt
         partitions:
           - id: esp-2
             type: esp
             size: 1G

2. Create a raid section in the storage section of your Trident Host Configuration that combines these partitions into a RAID array:

   storage:
     raid:
       software:
         - id: esp
           name: esp
           level: raid1
           devices:
             - esp-1
             - esp-2

Having created the RAID array, it can then be referenced to host the ESP filesystem:

storage:
  filesystems:
    - deviceId: esp
      mountPoint:
        path: /boot/efi
        options: umask=0077

With this configuration, Trident will set up the ESP on both disk partitions. When the machine boots, if the first disk partition has been corrupted or is invalid, the second will be used.