diff --git a/nixos/tests/all-tests.nix b/nixos/tests/all-tests.nix
index 8109ee869fa8..58950fafd903 100644
--- a/nixos/tests/all-tests.nix
+++ b/nixos/tests/all-tests.nix
@@ -1241,7 +1241,6 @@ in
   nebula-lighthouse-service = runTest ./nebula-lighthouse-service.nix;
   nebula.connectivity = runTest ./nebula/connectivity.nix;
   nebula.reload = runTest ./nebula/reload.nix;
-  nebula.tunless = runTest ./nebula/tunless.nix;
   neo4j = runTest ./neo4j.nix;
   netbird = runTest ./netbird.nix;
   netbird-relay = runTest ./netbird-relay.nix;
diff --git a/nixos/tests/nebula/connectivity.nix b/nixos/tests/nebula/connectivity.nix
index 3e96f613b11f..b7782815dc1c 100644
--- a/nixos/tests/nebula/connectivity.nix
+++ b/nixos/tests/nebula/connectivity.nix
@@ -1,6 +1,9 @@
-{ pkgs, lib, ... }:
+{
+  pkgs,
+  lib,
+  ...
+}:
 let
-
   # We'll need to be able to trade cert files between nodes via scp.
   inherit (import ../ssh-keys.nix pkgs)
     snakeOilPrivateKey
@@ -44,13 +47,11 @@ let
       }
       extraConfig
     ];
-
 in
 {
   name = "nebula";
 
   nodes = {
-
     lighthouse =
       { ... }@args:
       makeNebulaNode args "lighthouse" {
@@ -97,6 +98,24 @@ in
             };
           };
         };
+
+        # A lighthouse can run without a tun interface, no device name = skip length check pr 565501
+        services.nebula.networks.tunless = {
+          ca = "/etc/nebula/ca.crt";
+          cert = "/etc/nebula/lighthouse.crt";
+          key = "/etc/nebula/lighthouse.key";
+          isLighthouse = true;
+          listen = {
+            host = "0.0.0.0";
+            port = 4243;
+          };
+          tun = {
+            disable = true;
+            device = "nebula.tunless-too-long";
+          };
+          user = "nebula-smoke";
+          group = "nebula-smoke";
+        };
       };
 
     allowAny =
@@ -265,12 +284,10 @@ in
           };
         };
       };
-
   };
 
   testScript =
     let
-
       setUpPrivateKey = name: ''
         ${name}.start()
         ${name}.succeed(
@@ -379,6 +396,11 @@ in
       lighthouse.wait_until_succeeds("ping -c1 -W1 10.0.100.1", timeout=10)
       lighthouse.wait_until_succeeds("ping -c1 -W1 2001:db8::1", timeout=10)
 
+      # The tunless network starts without a tun device despite its (deliberately over-long) configured device name. pr 565501
+      lighthouse.wait_for_unit("nebula@tunless.service")
+      lighthouse.wait_until_succeeds("ss -lun | grep -q ':4243'", timeout=10)
+      lighthouse.fail("ip link show nebula.tunless-too-long")
+
       # Start all the machines to be set up
       allowAny.start()
       allowFromLighthouse.start()
diff --git a/nixos/tests/nebula/tunless.nix b/nixos/tests/nebula/tunless.nix
deleted file mode 100644
index dac1607e27e8..000000000000
--- a/nixos/tests/nebula/tunless.nix
+++ /dev/null
@@ -1,43 +0,0 @@
-{ ... }:
-{
-  name = "nebula";
-
-  nodes = {
-    lighthouse =
-      { pkgs, ... }:
-      {
-        environment.systemPackages = [ pkgs.nebula ];
-
-        services.nebula.networks.smoke = {
-          # Note that these paths won't exist when the machine is first booted.
-          ca = "/etc/nebula/ca.crt";
-          cert = "/etc/nebula/lighthouse.crt";
-          key = "/etc/nebula/lighthouse.key";
-          isLighthouse = true;
-          listen = {
-            host = "0.0.0.0";
-            port = 4242;
-          };
-          # A lighthouse can run without a tun interface. The device name is
-          # unused then, so the length assertion must not apply to it.
-          tun.disable = true;
-        };
-      };
-  };
-
-  testScript = ''
-    # Create the certificate and sign the lighthouse's keys.
-    lighthouse.succeed(
-        "mkdir -p /etc/nebula",
-        'nebula-cert ca -duration $((10*365*24*60))m -name "Smoke Test" -out-crt /etc/nebula/ca.crt -out-key /etc/nebula/ca.key',
-        'nebula-cert sign -duration $((365*24*60))m -ca-crt /etc/nebula/ca.crt -ca-key /etc/nebula/ca.key -name "lighthouse" -groups "lighthouse" -networks "10.0.100.1/24" -out-crt /etc/nebula/lighthouse.crt -out-key /etc/nebula/lighthouse.key',
-        'chown -R nebula-smoke:nebula-smoke /etc/nebula'
-    )
-
-    # Restart nebula to pick up the keys and verify it listens without creating a tun device.
-    lighthouse.systemctl("restart nebula@smoke.service")
-    lighthouse.wait_for_unit("nebula@smoke.service")
-    lighthouse.wait_until_succeeds("ss -lun | grep -q ':4242'", timeout=10)
-    lighthouse.fail("ip link show nebula.smoke")
-  '';
-}
diff --git a/pkgs/by-name/ne/nebula/package.nix b/pkgs/by-name/ne/nebula/package.nix
index 1da168e521e4..024c280c7a72 100644
--- a/pkgs/by-name/ne/nebula/package.nix
+++ b/pkgs/by-name/ne/nebula/package.nix
@@ -54,7 +54,6 @@ buildGoModule (finalAttrs: {
     inherit (nixosTests.nebula)
       connectivity
       reload
-      tunless
       ;
   };