Docker Basic Use and Command
Sungwa Yu
Published 10-13-2021 Modified 10-13-2021 392 Words 2 Mins

Reference: https://www.youtube.com/watch?v=3c-iBn73dDE

Pull Images

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docker pull image_name:image_tag

View Images

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docker images
docker image ls

Run Images

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docker run -d -p 8080:8081 --net my_network --name container_name image_name
  • If image not exists, will pull from repository.
  • -d: detached (not occupied terminal)
  • -p host_port:container_port

View Containers

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docker ps [-a]          # -a show hidden

Start/Stop Containers

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docker start container_id
docker stop container_id

Debug

Open Container Command Line

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docker exec -it container_id /bin/bash
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docker logs container_id

Network

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docker network ls
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docker create network my_network

Delete Images/Container

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docker image rm [OPTIONS] IMAGE [IMAGE...]
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docker rm [OPTIONS] CONTAINER [CONTAINER...]

Docker Compose

Run images together as a group. Don’t need to retype configuration, etc. 

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docker-compose -f docker-compose.yaml up
docker-compose -f docker-compose.yaml down

docker-compose.yaml Example

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version: '3'
services:
  my-app:
    image: 67832...r.ecr.us-east-2.amazonaws.com/my-app:latest
    ports:
    - 3000:3000
  mongodb:
    image: mongo:4.2.1
    ports:
      - 27017:27017
    environment:
      - MONGO_INITDB_ROOT_USERNAME=admin
      - MONGO_INITDB_ROOT_PASSWORD=password
    volumes:
      - mongo-data:/data/db
  mongo-express:
    image: mongo-express:0.54
    ports:
      - 8080:8081
    environment:
      - ME_CONFIG_MONGODB_ADMINUSERNAME=admin
      - ME_CONFIG_MONGODB_ADMINPASSWORD=password
      - ME_CONFIG_MONGODB_SERVER=mongodb
volumes:
  mongo-data:
    driver: local

Build Image

Build the image to push into the remote repository, ie. push to ECR and then deploy to ECS.

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docker build -t my-app:1.0 .

Dockerfile Example

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FROM node:13-alpine

ENV MONGO_DB_USERNAME=admin \
    MONGO_DB_PWD=password

RUN mkdir -p /home/app

COPY ./app /home/app

WORKDIR /home/app

RUN npm install

CMD ["node", "server.js"]

EXPOSE 8000

Docker Volumes

Note: Container restart all data will lose. Use Volumes to store data permanently.

Create Volume

Create volume while starting a container

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docker run -v volume_name:/container/path image_name

The above is the named volumes type.

Types of Volumes

Bind mount: mount host and container, data change both sides -v /host/path:/container/path

Anonymous volumes: -v /container/path

Named volumes (should use this one): give the volume a name then other container can refer to and shared and used data later.

Other Commands

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docker volume ls
docker volume create volume_name
docker volume rm volume_name

Note

  1. Volumes may not work for some path. For example, for MongoDB, work for /data/db but /data (might be some permission problems). Should refer to the doc or see the Dockerfile comes with the image from docker hub (image layers: VOLUME […]).

Snipaste_2021-10-12_23-15-45

  1. Even though used named volume, docker may still create some extra anonymous volumes for other uses.