+# Get the blockCount from the 'SWAP_SIZE' environmental variable
+blockCount=${SWAP_SIZE-''}
+
+# Validate SWAP_SIZE
+# Empty: Set blockCount 1
+# Zero: No Swap
+# Integer: Set blockCount
+# Else: No Swap
+case $blockCount in
+ '') blockCount=1 ;;
+ [0-9]*) ;;
+ *) exit ;;
+esac
+[[ $blockCount == 0 ]] && exit
+
+dd if=/dev/zero of=/swap count="${blockCount}k" bs=1MiB