diff --git a/nixos/tests/systemd-initrd-luks-fido2.nix b/nixos/tests/systemd-initrd-luks-fido2.nix
index 783b9d7426e7..3c191dcbf509 100644
--- a/nixos/tests/systemd-initrd-luks-fido2.nix
+++ b/nixos/tests/systemd-initrd-luks-fido2.nix
@@ -38,7 +38,6 @@
           };
         };
         virtualisation.rootDevice = "/dev/mapper/cryptroot";
-        virtualisation.fileSystems."/".autoFormat = true;
       };
     };
 
@@ -52,6 +51,8 @@
       # Create encrypted volume
       machine.wait_for_unit("multi-user.target")
       machine.succeed("echo -n supersecret | cryptsetup luksFormat -q --iter-time=1 /dev/vdb -")
+      machine.succeed("echo -n supersecret | cryptsetup luksOpen   -q               /dev/vdb cryptroot")
+      machine.succeed("mkfs.ext4 /dev/mapper/cryptroot")
       machine.succeed("PASSWORD=supersecret SYSTEMD_LOG_LEVEL=debug systemd-cryptenroll --fido2-device=auto /dev/vdb |& systemd-cat")
 
       # Boot from the encrypted disk