Title: Intro to Docker Containers
Speakers: Mike Raab

See my live blog table of contents from Oracle Cloud

History of containers

• ex: UNIX containers, Solairs Zones, VMWare
• Docker as a product and company made containerization easy

Use cases

• Ready to run application stacks – setting up a cluster can take a few days even if know what doing. Preparing Docker takes a few minutes once you have it configured.
• New development/microservices
• One time run jobs – the data dies with the container by default so good if don’t need it.
• Front end app servers
• Server density – Portable – can run same container anywhere

Architecture/Nomenclature

• VM has entire OS, app, dependencies, binaries, etc.. Container include the app and dependencies.
• Docker client – CLI for interfacing with Docker
• Dockerfile – text file of docker instructions to assemble image
• Image – hierarchies of files. Input to the docker build command. Collection if files and metadata. Contains layers.
• Container – running instance of an image using the docker run command.
• User doesn’t know whether you are using a container. Pure implementation.
• Registry – image repository. DockerHub is largest repo.
• Docker engine – container execution and admin. Uses Linux Kernel namespaces so have isolated workspaces. Can do Docker for Windows but different image and not popular. 99.9%+ Linux

Commands inside DockerFile

• FROM x – the base/parent image
• COPY x y – copy x to y
• RUN c – run UNIX command c
• ENTRYPOINT [“a”] – run command a at startup

Docker commands

• docker build -t dockerfile . – run in current directory
• docker tag image user/image
• docker push username/image
• docker pull username/image
• doker run – pull the image and run in container
• docker logs
• docker ps  – running docker containers
• docker ps – a – all docker containers whether running or not
• docker images – list all images
• docker rm
• docker tag
• docker login – login to registry
• docker push/pull
• docker inspect – config metadata
• docker-compose up -d – run multi container Docker applications

Why docker is hot

• developers love it
• fast to spin up environment
• open source
• code agility, CI/CD pipeline, devops
• portability
• managed kubernetes – running it is hard. use managed/cloud environments – oracle commercial time 🙂

My take

Good intro/review. I’m giving a session right after this one and wanted to get ready. So this was a good session for me. Not brand new content, but still go something out of it.