Define, build and modify container images

Andreas M. Antonopoulos is a RHEL Sysadmin who works for IBM on Watson integration with Red Hat Enterprise Linux Servers.

His RHEL Server: Andreas_RHEL_BTC_Server_06B

His username:

His professional standard: Competent RHEL Engineers NEVER run Linux commands as the root user.

His certifications: CompTIA Linux+, LPIC 1, 2 and 3, LFCS, RHCSA, RHCE. He is studying for a his Certified Kubernetes Application Developer (CKAD) certification.

His CKAD objective: Define, build and modify container images

Please generate and explain all of the commands that he will need to execute to prove that he has mastered this objective.

To demonstrate mastery of the Certified Kubernetes Application Developer (CKAD) objective of defining, building, and modifying container images, Andreas M. Antonopoulos may need to execute several commands. Here are some commands he could use:

  1. docker build: This command is used to build a container image based on a Dockerfile. Andreas can specify the location of the Dockerfile and provide a tag for the resulting image. For example:
    • docker build -t myimage:1.0 /path/to/Dockerfile
  2. docker images: This command lists the available container images on the system. Andreas can use it to verify that the image he built is present. For example:
    • docker images
  3. docker tag: Andreas can use this command to create a new tag for an existing image. This is useful when he wants to apply multiple tags to the same image. The command syntax is as follows:
    • docker tag source_image:source_tag new_image:new_tag
  4. docker push: When Andreas wants to share his container image with others, he can use this command to push the image to a container registry, such as Docker Hub or a private registry. For example:
    • docker push myusername/myimage:1.0
  5. docker rmi: If Andreas wants to remove a local container image, he can use this command. He needs to provide the image's repository and tag. For example:
    • docker rmi myimage:1.0
  6. docker commit: This command allows Andreas to create a new image from changes made to a running container. For example, if he has made modifications inside a container and wants to capture those changes as a new image, he can use:
    • docker commit container_id new_image:tag
  7. docker history: Andreas can use this command to view the history of an image, including the intermediate layers and commands used to create it. It helps in understanding the composition of the image. For example:
    • docker history myimage:1.0

These commands should provide Andreas with the necessary tools to define, build, modify, and manage container images as part of his CKAD objective. Remember that these commands assume he has Docker installed on his system, and he may need to adjust the commands based on his specific requirements and environment.


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