tektutor/ansible-1425June-2021

Setting up the Lab environment

The assumption is that you already have a CentOS 8.3.x 64-bit OS.

Installing Docker Community Edition

sudo yum install -y yum-utils
sudo yum-config-manager \
    --add-repo \
    https://download.docker.com/linux/centos/docker-ce.repo
sudo yum install docker-ce

Managing Docker Images

Start the docker service

sudo systemctl enable docker
sudo systemctl start docker
sudo usermod -aG docker jegan

You may have to replace the user 'jegan' with your username.

Listing the docker images in local registry

docker images

Download a docker image from Docker Hub to Local Docker Registry

docker pull hello-world:latest
docker pull ubuntu:16.04

Deleting a docker image

docker rmi hello-world:latest

Finding more details about the image

docker image inspect ubuntu:16.04

Managing Docker Containers

Creating a container in background(deattchaed/daemon) mode

docker run --dit --name ubutu2 --hostname ubuntu2 ubuntu:16.04 /bin/bash

Creating a container in interactive mode

docker run hello-world:latest
docker run --it --name ubuntu1 --hostname ubuntu1 ubuntu:16.04 /bin/bash

Coming out of the interactive container without exiting the container

Ctrl + p + q

Listing the currenly running containers

docker ps

Listing all containers

docker ps -a

Listing containers with a specific name pattern

docker ps --filter="name=ubuntu"
docker ps --filter="name=ubu"

Deleting containers matching a spectific name pattern

docker rm -f $(docker ps -q --filter="name=ubuntu") 

Finding IP Address of a container

docker inspect ubuntu1 | grep IPA
docker inspect -f {{.NetworkSettings.IPAddress}} ubuntu1

Stopping a running container

docker stop ubuntu1

Starting a stopped container

docker start ubuntu1

Docker rename container

docker rename old-container-name new-container-name

Restarting a container

docker restart ubuntu1

Getting inside a running container

docker exec -it ubuntu1 /bin/bash

Coming out of container

exit

Deleting a container graciously

docker stop ubuntu1
docker rm ubuntu1

docker stop ubuntu2 && docker rm ubuntu2

docker stop ubuntu1 ubuntu2 ubuntu3
docker rm ubuntu1 ubuntu2 ubuntu3

docker stop $(docker ps -q) && docker rm $(docker ps -aq)

Deleting a container forcibly

docker rm -f ubuntu1
docker rm -f $(docker ps -aq)