Docker

Installation:

• Download Docker Community Edition (Free)
  • to see Mac OS sw_vers
  • to see Linux OS cat /etc/*release*

Docker CLI

• Docker Command Line (CLI)
• Cheat Sheet

Docker Global

Command	Description
docker
docker version
docker info

Docker Container

Command	Description
docker container --help
docker container ls	List containers (docker ps)
docker container ls --help
docker container ls -a
docker container ls -aq | xargs docker container stop
docker container ls -aq | xargs docker container rm
docker stop $(docker ps -aq) && docker rm $(docker ps -aq) && docker rmi $(docker images -q)	Stop all containers, Remove all containers, Remove all images
docker container ls -aq | xargs docker container stop && docker container ls -aq | xargs docker container rm && docker images ls -aq | xargs docker rmi
docker container stop $(docker container ls -aqf name=memcached_api)
docker container run	Run a command in a new container (more things behind the scene)
docker container run --publish 80:80 --name mylocalhost --detach nginx	Host (Machine) Port : Docker Container Port
docker container run -p 80:80 --name mylocalhost -d nginx
docker container run -p 80:80 --name mylocalhost -it nginx bash	Run Interactive + allocate a pseudo-TTY
docker container port mylocalhost	80/tcp -> 0.0.0.0:80
docker container inspect --format '{{ .NetworkSettings.IPAddress }}' mylocalhost	172.17.0.2
docker container run -p 80:80 --name mylocalhost --network mynetwork -d nginx
docker container run -it --rm --name myos ubuntu	Remove container once exit (--rm)
docker container exec	Run a command in a running container
docker container exec -it ubuntu bash
docker container start	Start one or more stopped containers
docker container start -ai ubuntu	Start Interactive + allocate a pseudo-TTY
docker container stop	Stop one or more running containers
docker container rm	Remove one or more containers
docker container logs mylocalhost	Fetch the logs of a container
docker container logs -f mylocalhost	Fetch the logs of a container and follow it
docker container top mylocalhost	Display the running processes of a container
docker container inspect mylocalhost	Display detailed information on one or more containers
docker container stats	Display a live stream of container(s) resource usage statistics

Docker Network

Command	Description
docker network --help
docker network ls	List networks (bridge, host, none)
docker network inspect <network>	Display detailed information on one or more networks
docker network create --driver <network>	Create a network
docker network connect <network> <container>	Connect a container to a network
docker network disconnect <network> <container>	Disconnect a container from a network
docker network rm <network>	Remove one or more networks
docker network prune	Remove all unused networks

Docker Image

Command	Description
docker history IMAGE[:TAG]	Show the history of an image
docker image ls
docker image ls -a
docker image rm $(docker image ls -a | grep IMAGE)
docker image rm IMAGE[:TAG]
docker image pull IMAGE[:TAG]
docker image push IMAGE[:TAG]
docker image tag SOURCE_IMAGE[:TAG] TARGET_IMAGE[:TAG]
docker image build -t [:TAG] .
docker rmi $(docker images | grep "^<none>" | awk "{print $3}")	Remove all untagged images
docker image ls -a | grep "^<none>" | awk "{print $3}"	Remove all untagged images and intermediate images

Docker Log

Command	Description
docker login	always do logout after your done
docker logout

Docker Compose

Combination of command line tools CLI and a configuration file. Compose is a tool for defining and running multi-container Docker applications

Command	Description
docker-compose --help
docker-compose -f <docker-compose-file-name>
docker-compose up	setup volumes/networks and start all containers
docker-compose down	stop all containers and remove container/volume/networks
docker-compose down -v
docker-compose down -v --rmi

• docker-compose.yml is default config file but could be anything you want (use docker-compose -f <docker-compose-file-name>)

# if no version is specificed then v1 is assumed. Recommend v2 minimum
version: '3.1'

# containers. same as docker run
services:

    # a friendly name. this is also DNS name inside network
    servicename:
        
        # Optional if you use build:
        image:
        
        # Optional, replace the default CMD specified by the image
        command:
        
        # Optional, same as -e in docker run
        environment:
        
        # Optional, same as -v in docker run
        volumes:
        
    servicename2:

# Optional, same as docker volume create
volumes:

# Optional, same as docker network create
networks:

Docker File

• Dockerfile Reference

1. Create the Dockerfile
2. Build the Image

# FROM <image>[:tag]
### Sets the Base Image for subsequent instructions
### a valid Dockerfile must start with a FROM instruction

# COPY <src>... <dest>
### add directories and files to your Docker image

# ADD <src>... <dest>
### add directories and files to your Docker image
### has extra features compared to COPY that make ADD more unpredictable and a bit over-designed

# ENV <key> <value>
# ENV <key>=<value> ...
### used to define environment variables

# RUN <command>
# RUN ["executable", "param1", "param2"]
### will execute commands in a new layer
### RUN <command> will invoke a shell automatically (/bin/sh -c by default)

# VOLUME ["/var/log/", "/var/db"]
# VOLUME /var/log /var/db
### 
### creates a mount point with the specified name and marks it as holding externally mounted volumes from native host or other containers.

# USER <user>[:<group>]
### sets the user name (or UID) and optionally the user group (or GID) to use when running the image and for any RUN, CMD and ENTRYPOINT instructions that follow it in the Dockerfile

# WORKDIR </path/to/workdir>
### sets the working directory for any RUN, CMD, ENTRYPOINT, COPY and ADD instructions that follow it in the Dockerfil
### if the directory does not exists, Docker will create it for you.

# EXPOSE <port> [<port>/<protocol>...]
### informs Docker that the container listens on the specified network ports at runtime. 
### You can specify whether the port listens on TCP or UDP, and the default is TCP if the protocol is not specified.

# ENTRYPOINT ["executable", "param1", "param2"]
# ENTRYPOINT command param1 param2 (shell form)
### allows you to configure a container that will run as an executable 

# CMD ["executable","param1","param2"]
# CMD ["param1","param2"] (as default parameters to ENTRYPOINT)
# CMD command param1 param2 (shell form)
### to provide defaults for an executing container
### there can only be one CMD instruction in a Dockerfile. If you list more than one CMD then only the last CMD will take effect.

Docker Repositories

• Docker Store
• Docker Hub

References