"UserData": { "Fn::Base64" : { "Fn::Join" : ["\n" , [
          "#!/bin/bash",
          "set -o errexit",
          "apt update && apt -y install nginx",
          "while [ ! -e /dev/xvdd ]; do sleep 10; done",
          "parted /dev/xvdd mklabel msdos",
          "parted /dev/xvdd mkpart primary 0% 100%",
          "mkfs.ext4 -m 0 /dev/xvdd1 && mount /dev/xvdd1 /mnt"
        ]]}}
