mirroredBoots error, but only 1 device and 1 partition

[Sepero]

The error:

 Failed assertions:
- You cannot have duplicated devices in mirroredBoots

The disko

{ lib, ... }:

{
  disko.devices.disk.disk1 = {
    type = "disk";
    device = lib.mkDefault "/dev/vda";
    content = {
      type = "gpt";
      partitions = {
        root = {
          type = "EF02";
          size = "100%";
          content = {
            type = "btrfs";
            extraArgs = [ "-f" ];
            mountpoint = "/";
          };
        };
      };
    };
  };
}

I have successfully installed Grub to non-uefi partition setup similar to this many times. So I'm not sure if the problem here is with disko or me.

[sedlund]

probably look at the output of --show-trace to see where the other value is coming from.

[Sepero]

Warning: Permanently added '192.168.122.2' (ED25519) to the list of known hosts.
error:
       … while calling anonymous lambda
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/attrsets.nix:1529:14:
         1528|         zipAttrsWith (
         1529|           n: values:
             |              ^
         1530|           let

       … while calling the 'head' builtin
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/attrsets.nix:1534:13:
         1533|           if length values == 1 || pred here (elemAt values 1) (head values) then
         1534|             head values
             |             ^
         1535|           else

       … while calling anonymous lambda
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/attrsets.nix:1182:17:
         1181|         mapAttrs (
         1182|           name: value:
             |                 ^
         1183|           if isAttrs value && cond value then recurse (path ++ [ name ]) value else f (path ++ [ name ]) value

       … from call site
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/attrsets.nix:1183:85:
         1182|           name: value:
         1183|           if isAttrs value && cond value then recurse (path ++ [ name ]) value else f (path ++ [ name ]) value
             |                                                                                     ^
         1184|         );

       … while calling anonymous lambda
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:273:71:
          272|           # For definitions that have an associated option
          273|           declaredConfig = mapAttrsRecursiveCond (v: !isOption v) (_: v: v.value) options;
             |                                                                       ^
          274|

       … while evaluating the attribute 'value'
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:1084:7:
         1083|     // {
         1084|       value = addErrorContext "while evaluating the option `${showOption loc}':" value;
             |       ^
         1085|       inherit (res.defsFinal') highestPrio;

       … while evaluating the option `system.build.toplevel':

       … while evaluating the attribute 'mergedValue'
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:1131:5:
         1130|     # Type-check the remaining definitions, and merge them. Or throw if no definitions.
         1131|     mergedValue =
             |     ^
         1132|       if isDefined then

       … while evaluating a branch condition
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:1132:7:
         1131|     mergedValue =
         1132|       if isDefined then
             |       ^
         1133|         if all (def: type.check def.value) defsFinal then

       … while evaluating the attribute 'values'
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:1125:9:
         1124|       {
         1125|         values = defs''';
             |         ^
         1126|         inherit (defs'') highestPrio;

       … while evaluating a branch condition
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:1119:11:
         1118|           # Avoid sorting if we don't have to.
         1119|           if any (def: def.value._type or "" == "order") defs''.values then
             |           ^
         1120|             sortProperties defs''.values

       … while calling the 'any' builtin
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:1119:14:
         1118|           # Avoid sorting if we don't have to.
         1119|           if any (def: def.value._type or "" == "order") defs''.values then
             |              ^
         1120|             sortProperties defs''.values

       … while evaluating the attribute 'values'
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:1252:7:
         1251|     {
         1252|       values = concatMap (def: if getPrio def == highestPrio then [ (strip def) ] else [ ]) defs;
             |       ^
         1253|       inherit highestPrio;

       … while calling the 'concatMap' builtin
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:1252:16:
         1251|     {
         1252|       values = concatMap (def: if getPrio def == highestPrio then [ (strip def) ] else [ ]) defs;
             |                ^
         1253|       inherit highestPrio;

       … while calling the 'concatMap' builtin
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:1099:17:
         1098|         # Process mkMerge and mkIf properties.
         1099|         defs' = concatMap (
             |                 ^
         1100|           m:

       … while calling anonymous lambda
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:1100:11:
         1099|         defs' = concatMap (
         1100|           m:
             |           ^
         1101|           map (

       … while calling the 'map' builtin
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:1101:11:
         1100|           m:
         1101|           map (
             |           ^
         1102|             value:

       … while evaluating definitions from `/nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/nixos/modules/system/activation/top-level.nix':

       … from call site
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:1110:80:
         1109|               }
         1110|           ) (addErrorContext "while evaluating definitions from `${m.file}':" (dischargeProperties m.value))
             |                                                                                ^
         1111|         ) defs;

       … while calling 'dischargeProperties'
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:1203:5:
         1202|   dischargeProperties =
         1203|     def:
             |     ^
         1204|     if def._type or "" == "merge" then

       … while evaluating a branch condition
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:1204:5:
         1203|     def:
         1204|     if def._type or "" == "merge" then
             |     ^
         1205|       concatMap dischargeProperties def.contents

       … while evaluating the attribute 'value'
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/modules.nix:770:21:
          769|             inherit (module) file;
          770|             inherit value;
             |                     ^
          771|           }) module.config

       … from call site
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/nixos/modules/system/activation/top-level.nix:80:26:
           79|   # Handle assertions and warnings
           80|   baseSystemAssertWarn = lib.asserts.checkAssertWarn config.assertions config.warnings baseSystem;
             |                          ^
           81|

       … while calling 'checkAssertWarn'
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/asserts.nix:193:27:
          192|   checkAssertWarn =
          193|     assertions: warnings: val:
             |                           ^
          194|     let

       … while calling the 'throw' builtin
         at /nix/store/wwky6rfydvg8n4jpw4psh6x0wrd6c3qk-source/lib/asserts.nix:198:7:
          197|     if failedAssertions != [ ] then
          198|       throw "\nFailed assertions:\n${concatStringsSep "\n" (map (x: "- ${x}") failedAssertions)}"
             |       ^
          199|     else

       error:
       Failed assertions:
       - You cannot have duplicated devices in mirroredBoots

[sedlund]

this is the config that is being built on the remote by nixos-anywhere.

need to look at it before it tries to deploy.

use repl (replace grub with systemd if thats what you are using):

nix repl .# -Lv --show-trace
nix-repl> nixosConfigurations.<name>.config.boot.loader.grub.device
""

nix-repl> nixosConfigurations.<name>.config.boot.loader.grub.devices
[ "/dev/vda" ]

# this shouldnt happen - error i got before.  might show source of the two values
nix-repl> :p nixosConfigurations.<name>.config.boot.loader.grub.mirroredBoots
[ { devices = [ "/dev/sda" "/dev/sda" ]; efiBootloaderId = null; efiSysMountPoint = "/boot"; path = "/boot"; } ]

to work around it without finding what is causing the merge you can probably use:

boot.loader.grub.devices = lib.mkForce ["/dev/vda"];

[Sepero]

The work around did the trick for me. I could never have figured this out by myself. Thank you!