Docker.md

Docker Essentials

Docker demo steps

See Configuring your machine for the demo: Docker Demo

Basics

You make a image with docker compose You create a container running that image You compose a service

using partial Id for referencing images and containers

example: REPOSITORY TAG IMAGE ID CREATED SIZE quickstartidentityserver dev 17477555f987 11 minutes ago 509MB

Getting info : docker image inspect 17

docker database sqlexpress

download the public image like this : docker pull microsoft/mssql-server-windows-express run an instance like this ( password must be complex enough, otherwise login will fail, no other warning!) docker run --name demodb -d -p 1433:1433 -e sa_password=azurePASSWORD123 -e ACCEPT_EULA=Y microsoft/mssql-server-windows-express connect to the instance like this docker exec -it <DOCKER_CONTAINER_ID> sqlcmd or connect from SSMS: figure out ipaddress docker inspect –format="{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}" <DOCKER_CONTAINER_ID>

use it in SSMS

Docker commands

List Docker CLI commands

docker docker container --help

Display Docker version and info

docker --version docker version docker info

Execute Docker image

docker run hello-world

List Docker images

docker image ls

Remove images

docker image rm [container-id]

List Docker containers (running, all, all in quiet mode)

docker container ls docker container ls --all docker container ls -aq

Launch Docker swarm and start service

docker swarm init docker stack deploy -c docker-compose.yml getstarted docker stack rm getstarted // stop the service

docker swarm leave --force // take down the swarm

If you change the docker.compose.yml file and save, you can run the deploy command again, docker will handle the changes like start up more replica's if requested.

work with services

docker service ls docker service ps getstartedlab_web // Send ps command to linux host

docker ps --filter "status=running" --filter "name=demodb" --format {{.ID}} -n 1 docker inspect --format="{{.NetworkSettings.Networks.nat.IPAddress}}" d5d

Contents of a docker file

WORKDIR ADD RUN EXPOSE CMD

Example docker file

Use an official Python runtime as a parent image

FROM python:2.7-slim

Set the working directory to /app

WORKDIR /app

Copy the current directory contents into the container at /app

ADD . /app

Install any needed packages specified in requirements.txt

RUN pip install --trusted-host pypi.python.org -r requirements.txt

Make port 80 available to the world outside this container

EXPOSE 80

Define environment variable

ENV NAME World

Run app.py when the container launches

CMD ["python", "app.py"]

Componse the service with a docker-compose.yml

version: "3" services: web: # replace username/repo:tag with your name and image details image: username/repo:tag deploy: replicas: 5 resources: limits: cpus: "0.1" memory: 50M restart_policy: condition: on-failure ports: - "80:80" networks: - webnet

networks: webnet: