Merge remote-tracking branch 'nl6720/RouteMetric'

* nl6720/RouteMetric:
  configs/*/airootfs/etc/systemd/system/systemd-networkd-wait-online.service.d/wait-for-only-one-interface.conf: document why the drop-in file exists
  configs/releng/airootfs/etc/systemd/network/: move RouteMetric= from [DHCPv6] to [IPv6AcceptRA]

configs/baseline/airootfs/etc/systemd/network/20-ethernet.network

@@ -8,6 +8,3 @@ Name=eth*
 [Network]
 DHCP=yes
 IPv6PrivacyExtensions=yes
-
-[DHCP]
-RouteMetric=512

configs/baseline/airootfs/etc/systemd/system/systemd-networkd-wait-online.service.d/wait-for-only-one-interface.conf

 #
 # SPDX-License-Identifier: GPL-3.0-or-later
 
+# Allow systemd-networkd-wait-online to succeed with one interface, otherwise, if multiple network interfaces exist,
+# network-online.target gets needlessly delayed.
+# See https://wiki.archlinux.org/title/systemd-networkd#systemd-networkd-wait-online
 [Service]
+ExecStart=
 ExecStart=/usr/lib/systemd/systemd-networkd-wait-online --any

configs/releng/airootfs/etc/systemd/network/20-ethernet.network

@@ -9,8 +9,13 @@ Name=eth*
 DHCP=yes
 IPv6PrivacyExtensions=yes
 
+# systemd-networkd does not set per-interface-type default route metrics
+# https://github.com/systemd/systemd/issues/17698
+# Explicitly set route metric, so that Ethernet is preferred over Wi-Fi and Wi-Fi is preferred over mobile broadband.
+# Use values from NetworkManager. From nm_device_get_route_metric_default in
+# https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/blob/main/src/core/devices/nm-device.c
 [DHCPv4]
-RouteMetric=512
+RouteMetric=100
 
-[DHCPv6]
-RouteMetric=512
+[IPv6AcceptRA]
+RouteMetric=100

configs/releng/airootfs/etc/systemd/network/20-wlan.network

@@ -8,8 +8,13 @@ Name=wl*
 DHCP=yes
 IPv6PrivacyExtensions=yes
 
+# systemd-networkd does not set per-interface-type default route metrics
+# https://github.com/systemd/systemd/issues/17698
+# Explicitly set route metric, so that Ethernet is preferred over Wi-Fi and Wi-Fi is preferred over mobile broadband.
+# Use values from NetworkManager. From nm_device_get_route_metric_default in
+# https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/blob/main/src/core/devices/nm-device.c
 [DHCPv4]
-RouteMetric=1024
+RouteMetric=600
 
-[DHCPv6]
-RouteMetric=1024
+[IPv6AcceptRA]
+RouteMetric=600

configs/releng/airootfs/etc/systemd/network/20-wwan.network

@@ -8,8 +8,13 @@ Name=ww*
 DHCP=yes
 IPv6PrivacyExtensions=yes
 
+# systemd-networkd does not set per-interface-type default route metrics
+# https://github.com/systemd/systemd/issues/17698
+# Explicitly set route metric, so that Ethernet is preferred over Wi-Fi and Wi-Fi is preferred over mobile broadband.
+# Use values from NetworkManager. From nm_device_get_route_metric_default in
+# https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/blob/main/src/core/devices/nm-device.c
 [DHCPv4]
-RouteMetric=2048
+RouteMetric=700
 
-[DHCPv6]
-RouteMetric=2048
+[IPv6AcceptRA]
+RouteMetric=700

configs/releng/airootfs/etc/systemd/system/systemd-networkd-wait-online.service.d/wait-for-only-one-interface.conf

 #
 # SPDX-License-Identifier: GPL-3.0-or-later
 
+# Allow systemd-networkd-wait-online to succeed with one interface, otherwise, if multiple network interfaces exist,
+# network-online.target gets needlessly delayed.
+# See https://wiki.archlinux.org/title/systemd-networkd#systemd-networkd-wait-online
 [Service]
 ExecStart=
 ExecStart=/usr/lib/systemd/systemd-networkd-wait-online --any