From bb51c2d8fe4ba70d5400932f625c1e828708a60c Mon Sep 17 00:00:00 2001
From: Will Fancher <elvishjerricco@gmail.com>
Date: Sat, 16 Aug 2025 14:12:31 -0400
Subject: [PATCH] nixos/tests/snapper: Use autoFormat

---
 nixos/tests/snapper.nix | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/nixos/tests/snapper.nix b/nixos/tests/snapper.nix
index 4a03b85cc71d..b8a86c51d694 100644
--- a/nixos/tests/snapper.nix
+++ b/nixos/tests/snapper.nix
@@ -5,16 +5,18 @@
   nodes.machine =
     { pkgs, lib, ... }:
     {
-      boot.initrd.postDeviceCommands = ''
-        ${pkgs.btrfs-progs}/bin/mkfs.btrfs -f -L aux /dev/vdb
-      '';
-
-      virtualisation.emptyDiskImages = [ 4096 ];
+      virtualisation.emptyDiskImages = [
+        {
+          size = 4096;
+          driveConfig.deviceExtraOpts.serial = "aux";
+        }
+      ];
 
       virtualisation.fileSystems = {
         "/home" = {
-          device = "/dev/disk/by-label/aux";
+          device = "/dev/disk/by-id/virtio-aux";
           fsType = "btrfs";
+          autoFormat = true;
         };
       };
       services.snapper.configs.home.SUBVOLUME = "/home";