1. Docker concepts

Docker is a platform for developers and sysadmins to develop, deploy, and run applications with containers. The use of Linux containers to deploy applications is called containerization.

2. Containers and virtual machines

A container runs natively on Linux and shares the kernel of the host machine with other containers. It runs a discrete process, taking no more memory than any other executable, making it lightweight.

By contrast, a virtual machine (VM) runs a full-blown “guest” operating system with virtual access to host resources through a hypervisor. In general, VMs provide an environment with more resources than most applications need.

3. Commands - Run and Debug

• docker run -d -v redis-vol:/data redis:alpine -p run containers
• docker run -d -v redis-vol:/data redis
• docker run --entrypoint /bin/bash -it nodeais:2.4.4
• docker run -it -v /root:/root nodeais:2.4.3 bash
• docker exec -i 92a1 curl 127.0.0.1:9200 debug go into shell without interrupt the main container, recommendation
• docker exec -it 92a1 bash
• docker attach 69d1 attach will stop main process and return control here
• docker logs --tail=100 -f mongodb to get debug logs

4. Commands - Image

• docker pull library/elasticsearch:5.6 to pull es
• docker pull java:openjdk-8-jdk to pull java
• docker images list images
• docker image ls
• docker image ls mongo --format "{{.ID}}"
• docker image rm *id*
• docker build -t plugins-scripts:v23 . build image

5. Commands - Container

• docker container ls
• docker container ls -a to include stooped ones
• docker container rm *id*
• docker container prune remove all stopped containers
• docker ps is a short cut for docker container ls

6. Commands - Volumes

• docker volume ls
• docker volume create redis-vol
• docker run -d --name devtest --mount source=myvol2,target=/app nginx:latest
• docker run -d --name devtest -v myvol2:/app nginx:latest
• docker volume inspect my-vol
• docker volume rm my-vol
• docker run -d --name=nginxtest --mount source=nginx-vol,destination=/usr/share/nginx/html,readonly nginx:latest for read only
• docker run -d --name=nginxtest -v nginx-vol:/usr/share/nginx/html:ro nginx:latest for read only
• docker volume prune delete all unused

7. Commands - Network

• docker network create my-net bridge
• docker network create --driver=bridge --subnet=172.28.0.0/16 --ip-range=172.28.5.0/24 --gateway=172.28.5.254 br0
• docker network create -d macvlan --subnet=172.16.86.0/24 --gateway=172.16.86.1 -o parent=eth0 pub_net macvlan
• docker network rm my-net Remove network
• docker create --name my-nginx --network my-net --publish 8080:80 nginx:latest Connect by starting
• docker network connect my-net my-nginx Connect while started
• docker network disconnect my-net my-nginx Disconnect
• docker create --name my-nginx --network host --publish 8080:80 nginx:latest
• docker network prune all unused networks are removed

8. Commands - Format

• println print each line docker inspect --format='{{range .NetworkSettings.Networks}}{{println .IPAddress}}{{end}}' container

• docker inspect -f '{{range .NetworkSettings.Networks}}{{println .IPAddress}}{{end}}' get IP

  • upper : docker inspect --format "{{upper .Name}}" container
  • title : docker inspect --format "{{title .Name}}" container
  • split : docker inspect --format '{{split .Image ":"}}'
  • lower : docker inspect --format "{{lower .Name}}" container
  • json : docker inspect --format '{{json .Mounts}}' container
  • join : docker inspect --format '{{join .Args " , "}}' container

• Sample:

  docker inspect 7cb9995533cb | grep "IPAddress"
  
  .Service.ID Service ID
  .Service.Name       Service name
  .Service.Labels     Service labels
  .Node.ID    Node ID
  .Node.Hostname      Node Hostname
  .Task.ID    Task ID
  .Task.Name  Task name
  .Task.Slot  Task slot
  

9. Commands Tags, Save and Export

(Seems modern docker can remember the tag)

• docker image save b5435fede523 -o ./plugins-scrcips.2.3.0.180428.tar
• docker image load -i ./plugins-scrcips.2.3.0.180428.tar
• docker image tag b5435fede523 plugins-scripts:2.3.0
• docker image rmi plugins-scripts:2.3.0

10. Commands Others

• docker system prune remove all images, containers, and networks.
• docker run --rm -it --security-opt apparmor=docker-default hello-world security policy
• docker run -v /root:/root -e DISPLAY=$DISPLAY -v /tmp/.X11-unix:/tmp/.X11-unix -it node:6.14.0 /bin/bash Display (For LibreOffice/Chrome/FF)
• LABEL "com.example.vendor"="ACME Incorporated" to add labels
• bin/registry garbage-collect [--dry-run] /path/to/config.yml garbage collection

11. Reference

• https://docs.docker.com/get-started/