diff --git a/make_swap.sh b/make_swap.sh
index 0713cf8905..259aa68a6b 100644
--- a/make_swap.sh
+++ b/make_swap.sh
@@ -21,13 +21,14 @@ if [ `grep SwapTotal /proc/meminfo | awk '{ print $2; }'` -eq 0 ]; then
     elif [ -b /dev/xvde ]; then
         DEV='/dev/xvde'
     fi
+    SWAPFILE=/swapfile
+    MEMKB=`grep MemTotal /proc/meminfo | awk '{print $2; }'`
+    # Use the nearest power of two in MB as the swap size.
+    # This ensures that the partitions below are aligned properly.
+    MEM=`python3 -c "import math ; print(2**int(round(math.log($MEMKB/1024, 2))))"`
 
     # Avoid using config drive device for swap
     if [ -n "$DEV" ] && ! blkid | grep $DEV | grep TYPE ; then
-        MEMKB=`grep MemTotal /proc/meminfo | awk '{print $2; }'`
-        # Use the nearest power of two in MB as the swap size.
-        # This ensures that the partitions below are aligned properly.
-        MEM=`python3 -c "import math ; print(2**int(round(math.log($MEMKB/1024, 2))))"`
         if mount | grep ${DEV} > /dev/null; then
             echo "*** ${DEV} appears to already be mounted"
             echo "*** ${DEV} unmounting and reformating"
@@ -61,6 +62,16 @@ if [ `grep SwapTotal /proc/meminfo | awk '{ print $2; }'` -eq 0 ]; then
         perl -nle "m,${DEV}, || print" -i /etc/fstab
         echo "${DEV}1  none  swap  sw                           0  0" >> /etc/fstab
         echo "${DEV}2  /opt  ext4  errors=remount-ro,barrier=0  0  2" >> /etc/fstab
-        mount -a
+    elif [ ! -f "$SWAPFILE" ] ; then
+        # We don't have real devices to use so we make a swap file instead.
+        # Note you can skip this by precreating /swapfile.
+        # bs here is 1Mb
+        sudo dd if=/dev/zero of=${SWAPFILE} bs=1048576 count=${MEM}
+        sudo chown root:root $SWAPFILE
+        sudo chmod 600 $SWAPFILE
+        sudo mkswap $SWAPFILE
+        echo "${SWAPFILE}  none  swap  sw                       0  0" >> /etc/fstab
     fi
+    swapon -a
+    mount -a
 fi