Docker is a way of packaging applications and all of their required dependencies and configuration into a single image. Essentially, this turns your server configuration into something that can be managed with git and synchronized across every machine.
CDNs, or Content Delivery Networks, are made up of many edge servers all around the world, and cache your website’s content or static files for greater performance and significantly lower last-mile latency to the end user.
AWS’s Elastic Container Service (ECS) is a compute engine specifically designed for Docker containers. You can use it to deploy containers using underlying EC2 instances, or run a server-agnostic deployment on Fargate.
Most of us have done it—deployed temporary VMs to Azure. Something that many of us also have done is to forget to remove resources attached to those VMs when deleting them. This can lead to unwanted costs upwards to thousands of dollars if you’re not careful.
If you want to run a server in a private subnet, you’ll need to use a VPN to connect to it. AWS VPN is a managed OpenVPN service that can handle this for you, and allow you to lock down public access to your protected instances.