Containerization with Docker

Objectives

• what are containers
• what is docker and why is it needed
• what can docker do?
• run docker containers
• create docker images'
• networks in docker
• docker compose
• docker concepts in depth
• docker for windows and mac
• docker swarm
• docker vs kubernetes

why is docker needed?

• Compatibility with the OS issue
• Compatibility with versions of the components and libraries issue (matrix from hell)
• Delayed setting up of the environments for dev/test/prod

what are containers?

• containers offer an isolated environment from the host operating system
• circumvent the dependency issue as the dependencies can be packaged into the container
• the same existed as VMs before, but were clunky to set up and operate.
• docker is based on the LXC containers technology
• Containers share the underlying kernel
• Containers expect a Linux kernel.
• In Windows, docker uses the WSL layer to power the required kernel for the containers
• In Mac, the OS sets up a VM that provides the necessary kernel components for the containers