Hello, I am new-ish to NixOS and disko and am trying to get a setup working for my home server. I have this cut-down config that is just supposed to format the single mirror that I plan to install NixOS on top of, but it seems to not correctly create the zfs partition (as well as the zpool and datasets). When I run sudo disko --mode disko disko-config.nix, it appears to work (?), but when I check the partitions in Gnome Disks in the live environment, the content of the partition is listed as "Unknown." The EFI boot partition does appear to be recognized as expected. Any help would be much appreciated!

{
  disko.devices = let
    nixosPartitions = {
      ESP = {
        size = "512M";
        type = "EF00";
        content.type = "filesystem";
        content.format = "vfat";
        content.mountpoint = "/boot";
      };
      zfs = {
        size = "100%";
        content.type = "zfs";
        content.pool = "nixos";
      };
    };
  in {
    disk = {
      # NixOS boot mirror (240GBx2)
      ssd0 = {
        device = "/dev/sda";
        type = "disk";
        content = {
          type = "gpt";
          partitions = nixosPartitions;
        };
      };
      ssd1 = {
        device = "/dev/sdb";
        type = "disk";
        content = {
          type = "gpt";
          partitions = nixosPartitions;
        };
      };
    };
  };

  zpool = {
    # NixOS boot mirror
    nixos = {
      type = "zpool";
      mode = "mirror";
      options = { ashift = "12"; };
      datasets = {
        "root" = {
          type = "zfs_fs";
          mountpoint = "/";
          options = {
            encryption = "aes-256-gcm";
            keyformat = "passphrase";
            keylocation = "prompt";
          };
        };
        "nix" = {
          type = "zfs_fs";
          mountpoint = "/nix";
          options."com.sun:auto-snapshot" = "false";
        };
        "home" = {
          type = "zfs_fs";
          mountpoint = "/home";
          options = {
            encryption = "aes-256-gcm";
            keyformat = "raw";
            keylocation = "file:///etc/zfskey";
          };
        };
      };
    };
  };
}

I've managed to make a little more progress:

{
  disko.devices = let
    nixosPartitions = {
      ESP = {
        size = "512M";
        type = "EF00";
        content.type = "filesystem";
        content.format = "vfat";
        content.mountpoint = "/boot";
      };
      zfs = {
        size = "100%";
        content.type = "zfs";
        content.pool = "zpool-nixos";
      };
    };
  in {
    disk = {
      # NixOS boot mirror (240GBx2)
      ssd0 = {
        device = "/dev/sda";
        type = "disk";
        content = {
          type = "gpt";
          partitions = nixosPartitions;
        };
      };
      ssd1 = {
        device = "/dev/sdb";
        type = "disk";
        content = {
          type = "gpt";
          partitions = nixosPartitions;
        };
      };
    };

    zpool = {
      # NixOS boot mirror
      zpool-nixos = {
        type = "zpool";
        mode = "mirror";
        options = { ashift = "12"; };
        preCreateHook = ''
          # Create the temporary keyfile before any ZFS dataset is created
          head -c 32 /dev/urandom > /run/tmp-zfskey
          chmod 600 /run/tmp-zfskey
        '';
        datasets = {
          "root" =
            { # NOTE: Don't encrypt root dataset directly to allow flexibility later.
              type = "zfs_fs";
              mountpoint = "/";
            };
          "root/unlock" = {
            type = "zfs_fs";
            mountpoint = "/unlock";
            options = {
              encryption = "aes-256-gcm";
              keyformat = "passphrase";
              keylocation = "prompt";
            };
          };
          "root/nix" = {
            type = "zfs_fs";
            mountpoint = "/nix";
            options = {
              encryption = "aes-256-gcm";
              keyformat = "raw";
              keylocation = "file:///run/tmp-zfskey";
            };
          };
          "root/home" = {
            type = "zfs_fs";
            mountpoint = "/home";
            options = {
              encryption = "aes-256-gcm";
              keyformat = "raw";
              keylocation = "file:///run/tmp-zfskey";
            };
          };
        };
        postCreateHook = ''
          # Move the keyfile into the unlock dataset
          # cp /run/tmp-zfskey /mnt/unlock/zfskey
          # chmod 600 /mnt/unlock/zfskey

          echo "postCreateHook running" >> /tmp/disko-debug.log
          ls -lah /mnt/unlock >> /tmp/disko-debug.log 2>&1
          echo "before" >> /tmp/disko-debug.log 2>&1
          cp /run/tmp-zfskey /mnt/unlock/zfskey >> /tmp/disko-debug.log 2>&1
          echo "after" >> /tmp/disko-debug.log 2>&1
          chmod 600 /mnt/unlock/zfskey >> /tmp/disko-debug.log 2>&1
          ls -lah /mnt/unlock >> /tmp/disko-debug.log 2>&1

          # Update keylocation for other datasets (will be correct after reboot)
          zfs set keylocation=file:///unlock/zfskey zpool-nixos/root/nix
          zfs set keylocation=file:///unlock/zfskey zpool-nixos/root/home
        '';
      };
    };
  };
}

This mostly runs, but the postCreateHook has an issue with copying the key file. Not sure if I am going about this the right way, so any pointers would be much appreciated. I basically want to have just one dataset encrypted with a password, and then have all other encrypted datasets reference a key file stored on the password protected one so that I can unlock everything with just one password.

Are there any good examples of how to use the topsorted function? Doing some digging in nix repl for the mdadm example, I see this behavior:

nix-repl> inputs.nixpkgs.lib.lists.last nixosConfigurations.testmachine.config.disko.devices._meta.dev[
  "disk"
  "/dev/my-disk"
]

nix-repl> builtins.head nixosConfigurations.testmachine.config.disko.devices._meta.deviceDependencies.mdadm.raid1
[
  "disk"
  "/dev/my-disk"
]

Seems a bit odd only one element is in the list. And I wonder if this is why my new types are not getting ordered properly, because they follow the same structure as mdadm/mdraid.

Are there any good examples of how to use the topsorted function? Doing some digging in nix repl for the mdadm example, I see this behavior:

nix-repl> inputs.nixpkgs.lib.lists.last nixosConfigurations.testmachine.config.disko.devices._meta.deviceDependencies.mdadm.raid1[
  "disk"
  "/dev/my-disk"
]

nix-repl> builtins.head nixosConfigurations.testmachine.config.disko.devices._meta.deviceDependencies.mdadm.raid1
[
  "disk"
  "/dev/my-disk"
]

Seems a bit odd only one element is in the list. And I wonder if this is why my new types are not getting ordered properly, because they follow the same structure as mdadm/mdraid.

Are there any good examples of how to use the topsorted function? Doing some digging in nix repl for the mdadm example, I see this behavior:

nix-repl> inputs.nixpkgs.lib.lists.last nixosConfigurations.testmachine.config.disko.devices._meta.deviceDependencies.mdadm.raid1
[
  "disk"
  "/dev/my-disk"
]

nix-repl> builtins.head nixosConfigurations.testmachine.config.disko.devices._meta.deviceDependencies.mdadm.raid1
[
  "disk"
  "/dev/my-disk"
]

Seems a bit odd only one element is in the list. And I wonder if this is why my new types are not getting ordered properly, because they follow the same structure as mdadm/mdraid.

Are there any good examples of how to use the sortDevicesByDependencies function? Doing some digging in nix repl for the mdadm example, I see this behavior:

nix-repl> inputs.nixpkgs.lib.lists.last nixosConfigurations.testmachine.config.disko.devices._meta.deviceDependencies.mdadm.raid1
[
  "disk"
  "/dev/my-disk"
]

nix-repl> builtins.head nixosConfigurations.testmachine.config.disko.devices._meta.deviceDependencies.mdadm.raid1
[
  "disk"
  "/dev/my-disk"
]

Seems a bit odd only one element is in the list. And I wonder if this is why my new types are not getting ordered properly, because they follow the same structure as mdadm/mdraid.

reproduction steps:

      nixosConfigurations.testmachine = lib.nixosSystem {
        system = "x86_64-linux";
        modules = [
          ./tests/disko-install/configuration.nix
          # ./example/hybrid.nix
          ./module.nix
          # ./example/bcachefs-multi-disk.nix
          # ./example/mdadm.nix
          ./example/zfs-with-vdevs.nix
        ];

• add different examples to load and play around with
• load the flake into nix repl
• look at some of the _meta.deviceDependencies

reproduction steps:

      nixosConfigurations.testmachine = lib.nixosSystem {
        system = "x86_64-linux";
        modules = [
          ./tests/disko-install/configuration.nix
          # ./example/hybrid.nix
          ./module.nix
          # ./example/bcachefs-multi-disk.nix
          # ./example/mdadm.nix
          ./example/zfs-with-vdevs.nix
        ];

• add different examples to load and play around with toggling various configs
• load the flake into nix repl
• look at some of the _meta.deviceDependenciese

In reply to @lassulus:lassul.us
I will try to add that to my thaigersprint todo list tomorrow :D

In reply to @lassulus:lassul.us
I will try to add that to my thaigersprint todo list tomorrow :D