live-build/auto/build: If the image pre-installs network-manager, let it

manage all devices by default by shipping a default netplan policy.
Installing NM on an existing system only manages wifi and wwan, to avoid
interfering with networkd managed devices on existing server/cloud
instances.

debian/changelog

@@ -1,3 +1,13 @@
+livecd-rootfs (2.427) UNRELEASED; urgency=medium
+
+  * live-build/auto/build: If the image pre-installs network-manager, let it
+    manage all devices by default by shipping a default netplan policy.
+    Installing NM on an existing system only manages wifi and wwan, to avoid
+    interfering with networkd managed devices on existing server/cloud
+    instances.
+
+ -- Martin Pitt <martin.pitt@ubuntu.com>  Thu, 18 Aug 2016 08:37:39 +0200
+
 livecd-rootfs (2.426) yakkety; urgency=medium
 
   * live-build/ubuntu-core/hooks/400-create-apt-get-warning.binary

live-build/auto/build

@@ -716,3 +716,17 @@ case $PROJECT in
 		fi
 		;;
 esac
+
+# If the image pre-installs network-manager, let it manage all devices by
+# default. Installing NM on an existing system only manages wifi and wwan via
+# /usr/lib/NetworkManager/conf.d/10-globally-managed-devices.conf. When setting
+# the global backend to NM, netplan overrides that file.
+if [ -d chroot/usr/lib/NetworkManager ]; then
+    mkdir -p chroot/etc/netplan
+    cat <<EOF > chroot/etc/netplan/01-network-manager-all.yaml
+# Let NetworkManager manage all devices on this system
+network:
+  version 2
+  renderer: NetworkManager
+EOF
+fi