I want to use AWS for deploying an open source ACS software that uses mongodb to manage my CPE devices. I want it to manage thousands-tens of thousands of devices with minimal interruption. What services should i use and how much storage/memory/IOPS are suitable for this kind of server and device count?

I tried deploying one EC2 instance and modifying the volume every time i add devices but when I’m not monitoring the server 24/7 the storage becomes full and i spend a lot of time modifying the instance and expanding the file system and i don’t want to keep facing the same problem.