Merge "Only configure DHCP for real interfaces"

elements/dhcp-all-interfaces/README.md

@@ -3,8 +3,8 @@ Autodetect network interfaces during boot and configure them for DHCP
 The rationale for this is that we are likely to require multiple
 network interfaces for use cases such as baremetal and there is no way
 to know ahead of time which one is which, so we will simply run a
-DHCP client on all interfaces (except lo) that are visible on the first
-boot.
+DHCP client on all interfaces with real MAC addresses (except lo) that
+are visible on the first boot.
 
 The script /usr/local/sbin/generate-interfaces-file.sh will be called
 early in each boot and will scan available network interfaces and

elements/dhcp-all-interfaces/install.d/generate-interfaces-file.sh

@@ -51,10 +51,14 @@ function disable_interface() {
 }
 
 for interface in $(ls /sys/class/net | grep -v ^lo$) ; do
+  MAC_ADDR_TYPE="$(cat /sys/class/net/${interface}/addr_assign_type)"
+
   echo -n "Inspecting interface: $interface..."
   if ifquery $interface >/dev/null 2>&1 ; then
     echo "Has config, skipping."
-  else
+  elif [ "$MAC_ADDR_TYPE" != "0" ]; then
+    echo "Device has generated MAC, skipping."
+   else
     ip link set dev $interface up >/dev/null 2>&1
     HAS_LINK="$(get_if_link $interface)"