This lesson is in the early stages of development (Alpha version)

Reproducible Computational Environments using Containers: Glossary

Key Points

Introducing Containers
  • Almost all software depends on other software components to function, but these components have independent evolutionary paths.

  • Projects involving many software components can rapidly run into a combinatoric explosion in the number of software version configurations available, yet only a subset of possible configurations actually works as desired.

  • Containers collect software components together and can help avoid software dependency problems.

  • Virtualisation is an old technology that container technology makes more practical.

  • Docker is just one software platform that can create containers and the resources they use.

Introducing the Docker command line
  • A toolbar icon indicates that Docker is ready to use containers.

  • You will typically interact with Docker using the command line.

Exploring and Running Containers
  • The docker pull command downloads Docker images from the internet.

  • The docker image command lists Docker images that are (now) on your computer.

  • The docker run command creates running containers from images and can run commands inside them.

  • When using the docker run command, a container can run a default action (if it has one), a user specified action, or a shell to be used interactively.

Finding Containers on the Docker Hub
  • The Docker Hub is an online repository of container images.

  • Many Docker Hub images are public, and may be officially endorsed.

  • Each Docker Hub page about an image provides structured information and subheadings

  • Most Docker Hub pages about images contain sections that provide examples of how to use those images.

  • Many Docker Hub images have multiple versions, indicated by tags.

  • The naming convention for Docker containers is: OWNER/CONTAINER:TAG

Cleaning Up Containers
  • The docker container command lists containers that have been created.

Creating your own container images
  • Dockerfiles specify what is within Docker images.

  • The docker build command is used to build an image from a Dockerfile

  • You can share your Docker images through the Docker Hub so that others can create Docker containers from your images.

Creating More Complex Container Images
  • You can include files from your Docker host into your Docker images by using the COPY instruction in your Dockerfile.

  • Docker allows containers to read and write files from the Docker host.

Creating containers in the cloud
  • You can create Docker containers on cloud computing resources just using a web browser.

  • Bitbucket is an online repository storage service that can create Docker containers to perform computation in response to files changing in your repositories.

Containers used in generating this lesson
  • The generation of this lesson website can be effected using a container.