Ch10

Containers🔗

The problems of Monolithic Application

Containers differ from VMs becuase it is always same under the effect of some config file that creates the image, no matter what Host OS is. Container Enginer (Docker) is responsible for this. While VMs can be quite large in size, and can be platform/host OS dependent.
Hypervisor can help orchestrate bunch of VMs
ECS (based on Docker) is container Orchestration Platform

2 Ways to setup

Fully managed docker container registry, built in Amazon ECS
helps in hosting images with bunch of nice features
To run container on EC2, we will need Task Definitions
Task Definitions (Important, asked in my exam lol)
- Configuring Memory Limits
- Network Details : ports mapping etc
- Container Details : names, tagging
ECS Service : allows to manage, run, maintain a specific number of task definitions within an amazon ECS Cluster.
- Self Healing Clusters
- Allows to setup ELB in front of Containers

When should we use Serverless v/s ECS

Servered	Serverless
Workload supports long-running operations	Cost Effective
Fully Utilizes the CPU and Memory	Lower Development Cost
	Reduced Operational Cost
	Better Scalability

Fargate is always using AWS VPC mode network while ECS gives flexibility to use any mode.

Three Networking Modes

Kubernetes is open-source container orchestration tool designed to automate, deploy, scale and operate containerised application.
It can grow from tens, thousands or even millions of containers
Its container runtime agnostic

Managed service allowing you to run Kubernetes across your AWS Infra without having to take care provisioning and running Kubernetes Management Infrastructure in Control Plane
You only need to provision and maintain the Worker Nodes

Control Plane : # of different APIs. The Kubelet processes Kubernetes Master.

**Nodes ** : EC2 Instances