5.2. Docker Basics¶
5.2.1. Docker Lingo¶
- Images
- Containers
- Image layers
- Ephemeral
- Volumes
- Network
- Port forwarding
- Docker files
5.2.2. Simple Demo¶
1. Download Ubuntu image:
user@host: docker pull ubuntu:latest
2. List images:
user@host: docker image ls
3. Simple temporary container:
user@host: docker run -ti —rm --name test1 ubuntu:latest /bin/sh
4. List instances:
user@host: docker ps -a
5. Simple daemonized container:
user@host: docker run -d -ti --name test2 ubuntu:latest /bin/sh
6. Attach terminal:
user@host: docker attach test2
7. Stop container:
user@host: docker stop test2
8. Start container:
user@host: docker start test2
5.2.3. Web Server Demo¶
1. nginx sample config as http directory listing:
daemon off;
user nginx;
worker_processes 1;
error_log /var/log/nginx/error.log warn;
pid /var/run/nginx.pid;
events {
worker_connections 1024;
}
http {
include /etc/nginx/mime.types;
default_type application/octet-stream;
sendfile on;
keepalive_timeout 65;
server {
listen 80;
location / {
root /usr/share/nginx/data;
autoindex on;
}
}
}
2. Dockerfile: ubuntu + nginx + default config file
# base container image
FROM ubuntu:18.04
# install packages
RUN export DEBIAN_FRONTEND=noninteractive && \
apt update --fix-missing && apt upgrade -y && \
apt install -y sudo locales nginx
# generate locale
RUN locale-gen en_US.UTF-8 && locale-gen --no-purge --lang en_US.UTF-8
# create a nginx user
RUN useradd -M --home /nonexistent --shell /usr/sbin/nologin nginx
# set default configuration
COPY nginx.conf /etc/nginx/nginx.conf
# default command at startup is nginx daemon
ENTRYPOINT [ "nginx" ]
3. Build container image from Dockerfile:
user@host: docker build -t nginx-http-share .
4. Start web server service:
user@host: docker run --rm -ti -p 80:80 \
-v </full/path/to/share/>:/usr/share/nginx/data nginx-http-share
- The web server is accessible on localhost port 80
5.2.4. References¶
- https://docs.docker.com/reference/
- https://www.youtube.com/watch?v=UV3cw4QLJLs (watch at 1.5x speed)
- http://takacsmark.com/getting-started-with-docker-in-your-project-step-by-step-tutorial/
- https://www.youtube.com/watch?v=6Er8MAvTWlI
- https://docs.docker.com/engine/userguide/storagedriver/imagesandcontainers/
- https://12factor.net/processes https://docs.docker.com/engine/tutorials/dockervolumes/
- https://deis.com/blog/2016/docker-storage-introduction/
- https://learning-continuous-deployment.github.io/docker/container/volumes/2015/05/22/persistent-data-with-docker/
- https://github.com/wsargent/docker-cheat-sheet
- https://blog.phusion.nl/2015/01/20/docker-and-the-pid-1-zombie-reaping-problem/