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There is a maximum of 30 database per instance and 4 TB on each instance, so if your application depends on an architecture where you need to have 100 databases in the same instance then this is a showstopper for RDS.

Difference between Database AS A Service(Dbaas) and Infrastructure As A Service(Iaas)

Container Orchestration: Docker Swarm Kubernetes ECS ECS Cluster :  is a logical grouping of container instances. It can contain one or more container instances. Container instances : is nothing but an EC2 instance with three more things on it. ECS Agent is installed on the container instances Docker is also installed It should register to an ECS Cluster Service  — Defines long-running tasks of the same Task Definition. This can be one running container or multiple running containers all using the same Task Definition. A Scheduling logic that decides when containers should run. Tasks : A logical group of running containers running on an instance. ECS Task Definition:  Docker image for each Container CPU and Memory Requirements for each container Links between Containers Networking and Port Settings Data Storage Volumes Security (IAM) Roles ...