AWS Elastic Beanstalk (Docker)

Single-container Docker

• Single Docker container per EC2 instance
• Run from Dockerfile or Dockerrun.aws.json
  • can be bundled with source code and deployed as .zip

Multi-container Docker

• Multiple Docker containers per EC2 instance
• Uses ECS underneath
  • ECS Cluster
  • ECS Task Definition = Dockerrun.aws.json
  • ECS Task
    • Run on every container instance in the environment
  • ECS Data Volumes
    • EB Creates log volumes
• Does not support Dockerfile
  • image must be built and uploaded to Docker repo
• Application is deployed on the container instance and mounted to the container

Preconfigured Containers

• Single container docker
• Based on stacks officially supported by Docker Official Repositories
• Cannot use configuration files to customize
• Can use Dockerfile

Dockerrun.aws.json (version 1)

• Used by single-container deployments
• Describes how to run Docker container on EB
• Overlaps with Dockerfile (can be used instead of it)
• Structure
  • AWSEBDockerrunVersion
    •  1
  • Authentication
    • Bucket/Key to the authentication configuration file (see below)
  • Image (see FROM)
  • Ports (see EXPOSED)
  • Volumes
    •  EC2 host volumes mapped to container (hostDirectory->containerDirectory)
  • Logging
    • Folder where application keeps logs
    • EB uploads the logs to S3 when "tail" or "bundle" requested
    • If you move to /rotated they will get uploaded as well

Dockerrun.aws.json (version 2)

• Used by multi-container deployments
• Structure
  • AWSEBDockerrunVersion
    
    • 2
  • Authentication
    • Same as 1
  • Volumes
    • mount points
    • allow container to "see" the folder
    • source code is deployed to container instance (/var/app/current)
    • EB configures additional volume for logs
      • one for each container
      • /var/log/containers/$containername
  • ContainerDefinitions (uses ECS Task format)
    
    • Name
    • Image
      • Same as 1
    • Environment
      • Environmental variables
    • Essential
      • Should the ECS Task stop if the container fails
    • Memory
      • Quota
    • Mount Points
      • Volumes from the container instance to mount
        
      • References Volumes section
    • PortMappings
      • hostPort -> containerPort
    • Links
      • Containers to link

Docker Authentication configuration file

• Login details for the Docker repo
• Stored in S3
• Referenced by Dockerrun.aws.json
• Read by EB to pull a Docker container from private repo