From ff3a0a4565cf666bf316337b00563219decf5b73 Mon Sep 17 00:00:00 2001
From: rnhmjoj <rnhmjoj@inventati.org>
Date: Fri, 1 May 2026 16:30:48 +0200
Subject: [PATCH] nixos/networking-interfaces-scripted: add fix for systemd
 initrd

When systemd is used in stage 1 (boot.initrd.systemd.enable), the device
units are activated before the stage 2 units are loaded, so the
network-addresses-*.service are never started.

To avoid this, in addition to the wantedBy dependency, we use udev rules
with SYSTEMD_WANTS to trigger the services directly.
---
 .../modules/tasks/network-interfaces-scripted.nix | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/nixos/modules/tasks/network-interfaces-scripted.nix b/nixos/modules/tasks/network-interfaces-scripted.nix
index 4bf274d4157f..7961cb21ff5a 100644
--- a/nixos/modules/tasks/network-interfaces-scripted.nix
+++ b/nixos/modules/tasks/network-interfaces-scripted.nix
@@ -888,9 +888,18 @@ let
       description = "NixOS scripted networking setup";
     };
 
-    services.udev.extraRules = ''
-      KERNEL=="tun", TAG+="systemd"
-    '';
+    services.udev.extraRules = lib.concatStringsSep "\n" (
+      [ ''KERNEL=="tun", TAG+="systemd"'' ]
+      # This creates a udev rule to start each service with a WantedBy
+      # dependency on a device unit. It's needed because if the service
+      # unit is loaded in stage 2 but its device was already up by
+      # stage 1, systemd will not automatically start it.
+      ++ lib.forEach (lib.attrNames cfg.interfaces) (
+        iface:
+        ''ACTION=="add", SUBSYSTEM=="net", KERNEL=="${iface}", ''
+        + ''ENV{SYSTEMD_WANTS}="network-addresses-${iface}.service"''
+      )
+    );
 
   };