docker笔记

Docker basics

1.Learn about images and containers

docker run hello-world执行命令的组成：

An image is a filesystem and parameters to use at runtime. It doesn’t have state and never changes. A container is a running instance of an image. When you ran the command, Docker Engine:

1.checked to see if you had the hello-world software image 2.downloaded the image from the Docker Hub (more about the hub later)
3.loaded the image into the container and “ran” it

2.Find and run the whalesay image

People all over the world create Docker images. You can find these images by browsing the Docker Hub.这么方便？

3.Build your own image

Step 1: Write a Dockerfile

A Dockerfile is a recipe which describes the files, environment, and commands that make up an image.

Remember that if you are using macOS or Windows, you are still creating an image which runs on Linux.

Step 2: Build an image from your Dockerfile

Step 3: Learn about the build process

Step 4: Run your new docker-whale

4.Create a Docker Hub account and repository

5.Tag, push, and pull your image

更多关于docker的知识

Define and deploy your app

1.Sample app overview

之前我们用Dockerfile来build,run whalesay app.

For this tutorial, the images are pre-built, and we use a stack file instead of a Dockerfile to specify the images. When we deploy, each image will run as a service in a container (or in multiple containers, for those that have replicas defined to scale the app).一个docker-stack.yml参考例子：

version: "3"services:  redis:    image: redis:alpine    ports:      - "6379"    networks:      - frontend    deploy:      replicas: 2      update_config:        parallelism: 2        delay: 10s      restart_policy:        condition: on-failure  db:    image: postgres:9.4    volumes:      - db-data:/var/lib/postgresql/data    networks:      - backend    deploy:      placement:        constraints: [node.role == manager]  vote:    image: dockersamples/examplevotingapp_vote:before    ports:      - 5000:80    networks:      - frontend    depends_on:      - redis    deploy:      replicas: 2      update_config:        parallelism: 2      restart_policy:        condition: on-failure  result:    image: dockersamples/examplevotingapp_result:before    ports:      - 5001:80    networks:      - backend    depends_on:      - db    deploy:      replicas: 1      update_config:        parallelism: 2        delay: 10s      restart_policy:        condition: on-failure  worker:    image: dockersamples/examplevotingapp_worker    networks:      - frontend      - backend    deploy:      mode: replicated      replicas: 1      labels: [APP=VOTING]      restart_policy:        condition: on-failure        delay: 10s        max_attempts: 3        window: 120s      placement:        constraints: [node.role == manager]  visualizer:    image: dockersamples/visualizer:stable    ports:      - "8080:8080"    stop_grace_period: 1m30s    volumes:      - "/var/run/docker.sock:/var/run/docker.sock"    deploy:      placement:        constraints: [node.role == manager]networks:  frontend:  backend:volumes:  db-data:

2.Set up Dockerized machines

3.Create a swarm

4.Deploy the application