nixos/networkd: Make activatible through dbus and netlink

With this systemd buffers netlink messages in early boot from the kernel
itself; and passes them on to networkd for processing once it's started.
Makes sure no routing messages are missed.

Also makes an alias so that dbus can activate this unit. Upstream has
this too.

1 files changed, 9 insertions, 1 deletions

diff --git a/nixos/modules/system/boot/networkd.nix b/nixos/modules/system/boot/networkd.nix
index 9b34b12e73a5..b0545363b330 100644
--- a/nixos/modules/system/boot/networkd.nix
+++ b/nixos/modules/system/boot/networkd.nix
@@ -1178,14 +1178,22 @@ in
       users.users.systemd-network.group = "systemd-network";
 
       systemd.additionalUpstreamSystemUnits = [
-        "systemd-networkd.service" "systemd-networkd-wait-online.service"
+        "systemd-networkd-wait-online.service"
+        "systemd-networkd.service"
+        "systemd-networkd.socket"
       ];
 
       systemd.network.units = mapAttrs' (n: v: nameValuePair "${n}.netdev" (netdevToUnit n v)) cfg.netdevs
         // mapAttrs' (n: v: nameValuePair "${n}.network" (networkToUnit n v)) cfg.networks;
 
+      # systemd-networkd is socket-activated by kernel netlink route change
+      # messages. It is important to have systemd buffer those on behalf of
+      # networkd.
+      systemd.sockets.systemd-networkd.wantedBy = [ "sockets.target" ];
+
       systemd.services.systemd-networkd = {
         wantedBy = [ "multi-user.target" ];
+        aliases = [ "dbus-org.freedesktop.network1.service" ];
         restartTriggers = map (x: x.source) (attrValues unitFiles);
         # prevent race condition with interface renaming (#39069)
         requires = [ "systemd-udev-settle.service" ];