17_12_docker.md

Docker from sketch

AUFS

• FS in stacks
• Every FS stack (hash) -> image/template
• docker run spawns Container (from image?)

Docker registry

• Ex: Dockerhub
• Image Upload/Download

Alpine vs Ubuntu

• Alpine 5-7 MB (w/o glibc) vs. several 100MB Ubuntu

Dockerfile

• FROM
• RUN Commands/Changes
• Entrypoint
• Every command => Own stack => Lots of inline and cleanup (e.g. rm -rf /var/lib/apt/lists/)

docker-compose

• Problem: Often need for multiple containers that interact with each other (Apache/MySQL)
• Defines images that start together, ports, hosts, ...

random notes

• ssh'ing in an changing things would be a concept fraction
• -v mount volume (even /tmp/x11socket possible lol)

vs. vagrant / ansible

• Vagrant full VM with OS etc
• Docker process runs on host system

Alternatives

• rkt