Cloudyeti-ECS-Series

Getting Started

• let's build the docker image locally
  • make app-up
  • make app-up app=nginx (will make only nginx up)
• Let's create a repository in ECR
  • make ecr-repo
• Let's push our image to ECR
  • make push-image

Docker useful commands

List all containers (add -a flag a last of below command to see info about stopped container)

• docker ps

List all the images

• docker images

Stop all containers

• docker stop $(docker ps -aq)

Remove all containers

• docker rm $(docker ps -aq)

deleting - all stopped containers - all networks not used by at least one container - all dangling images - all dangling build cache

• docker system prune

delete all unused images and volumes

• docker system prune --all

Amazon ECS

• Amazon Elastic Container Service (Amazon ECS) is a highly scalable, high-performance container orchestration service that supports Docker containers and allows you to easily run and scale containerized applications on AWS.

ECS Lauch Types

• EC2
• FARGATE: with fargate, we can deploy and manage container without having to provision or manage EC2 instances at all.

What are Services and Tasks

• Services: Services supervise tasks, it's job is to keep your task running. If task get's stopped, service will bring it back.
• Tasks: It is the wrapper to run your container. We specify our container configuration definition including cpu, ram, image, etc, in task definitions.

Service Discovery

• ECS Service Discovery is powered by Route 53 (AWS DNS Service). ECS updates a service registry provided by Route 53 based on task registration and health checks. Route 53 responds to DNS queries made by your containers with IP address and port using Multivalue Answer Routing. So, as the task scale up and down, the records for ip address in Route 53 are also updated.
• Service Discovery uses AWS Cloud Map API actions to manage HTTP and DNS namespaces for your Amazon ECS services.
• Service Discovery is crutial for all sorts of use case for managing microservices including communication between services in ECS as well as for Blue/Green deployment.

Deploying Docker Containers on AWS

• https://docs.docker.com/engine/context/ecs-integration/

Deploy Containers to AWS using Docker ECS Plugin

• Referral links:

  • https://www.docker.com/blog/from-docker-straight-to-aws/
  • https://github.com/docker/compose-cli

• First things first, go to this link https://docs.docker.com/engine/context/ecs-integration/#prerequisites and download the docker version that supports integration with ECS by clicking on Download for Mac or Download for Windows depending on your OS.

• Second step is to, enable Amazon ECS ARN and resource ID settings for container instance, service and task and save it.

  • https://console.aws.amazon.com/ecs/home?region=us-east-1#/settings

• Third step, create a new ecs context. See below:

Create ecs context for aws

docker context create ecs aws
Select AWS Profile new profile
profile name default
Region us-east-1
Enter credentials: N
Successfully created ecs context "aws"

Docker context (for working both in local and remote(forex: aws))

docker context ls --> to see list of context
docker context use < CONTEXT > --> for selecting the context

To specify your compose file use --file flag (otherwise it seeks for docker-compose.yml file by default) and to specify your cluster name use "--project-name" flag (otherwise it will take cluster with the name of present working directory). see below example:

docker compose --file ecs-compose.yml --project-name wordpress up