Configure eth0 within images

src/freedombone-image-customise

         return
     fi
 
+    { echo '# This file describes the network interfaces available on your system';
+      echo '# and how to activate them. For more information, see interfaces(5).';
+      echo 'source /etc/network/interfaces.d/*'; } > "$rootdir/etc/network/interfaces"
+
     if [[ "$GENERIC_IMAGE" == "no" ]]; then
-        echo '# This file describes the network interfaces available on your system' > "$rootdir/etc/network/interfaces"
-        echo '# and how to activate them. For more information, see interfaces(5).' >> "$rootdir/etc/network/interfaces"
-        echo 'source /etc/network/interfaces.d/*' >> "$rootdir/etc/network/interfaces"
 
-        echo "auto eth0
-iface eth0 inet static
-    address $BOX_IP_ADDRESS
-    netmask 255.255.255.0
-    gateway $ROUTER_IP_ADDRESS" > "$rootdir/etc/network/interfaces.d/static"
+        { echo 'auto eth0';
+          echo 'iface eth0 inet static';
+          echo "address $BOX_IP_ADDRESS";
+          echo 'netmask 255.255.255.0';
+          echo "gateway $ROUTER_IP_ADDRESS"; } > "$rootdir/etc/network/interfaces.d/static"
 
         hexarray=( 1 2 3 4 5 6 7 8 9 0 a b c d e f )
         a=${hexarray[$RANDOM%16]}${hexarray[$RANDOM%16]}
         d=${hexarray[$RANDOM%16]}${hexarray[$RANDOM%16]}
         e=${hexarray[$RANDOM%16]}${hexarray[$RANDOM%16]}
         echo "hwaddress ether de:$a:$b:$c:$d:$e" > "$rootdir/etc/network/interfaces.d/macaddress"
+    else
+        { echo 'auto eth0';
+          echo 'iface eth0 inet dhcp'; } > "$rootdir/etc/network/interfaces.d/dynamic"
     fi
 
     # configure DNS