DevOps Classroom Series – 07/Nov/2020

Storing and distributing docker Images

• As of now we can build docker images for the application by creating a Dockerfile
  • right base image
  • steps to install / configure your application
  • ports used by application
  • commands to start/run your app
• Workflow:
• Now Lets realize this workflow for gameoflife
• Whenever a new version of commited a new Docker image can be generated. Dockerfile is created generally in the source-code archive. Refer Here
• Whenever the code is commited we can generate a Dockerimage with a new tag. This tag is build locally on some machine, but it should be made available to others (In Enteprise means other members, In public means anyone)
• Lets get Started with using a Default Registry called as DockerHub
• Lets build the docker image

docker image build -t gameoflife:07112020 .

• Now create a tag that matches repository name

docker image tag gameoflife:07112020 qualitythought/gameoflife:07112020

• Now lets execute

docker login # Enter docker hub credentials

• Now the docker image is available for others

• Now lets use azure container registry. Refer Here for creating a docker registry in azure cloud

• screenshots

• Lets do the same with AWS Elastic Container Registry

• Now install aws cli. Refer Here

• Docker Trusted Registry:

  • This registry is part of Docker Enterprise
  • This registry integrates with LDAP

• Artifactory (Jfrog) Docker Registry

• Docker Registry: This docker image can be used as registry Refer Here

Managing Docker Containers

• We have already discussed running containers in
  • foreground
  • detached
  • interactive
• when we create a docker container every container will have a name and id.
• docker container is started in a detached mode. Is there any way to login into it
  • execute docker attach <cont-id or name>
  • execute docker container exec -it <cont> /bin/bash
• Remove all running docker containers
• Remove all docker containers in running and stopped state
• Logs: The logs command will show all the stdout stream of your contianer
• To list the running processes in your container use top command
• The stats provides real-time information on the specified container or if you don’t pass name or id it shows for all the running containers docker container stats
• Limiting Resources to container
  • Lets execute docker container run --help
  • Refer Here for commandline documentation
• Lets inspect containers
• Docker container states