26 July 2022

Docker Commands Cheat Sheet

run container

docker run

run container and drop to shell

docker run -it 
docker run --interactive --tty

run container in background 

docker run -d

container restart setings

docker run --restart (always|no|on-failure[:maxretries]|unless-stopped)

remove container when exited

docker run --rm

view containers running

docker container ls
docker container ls -a

start container

docker start

stop container

docker stop

remove container

docker rm

remove all stopped

docker container prune

rename container

docker rename

view containers metrics

docker stats []

copy file into container

docker cp file.ext :/path/to/folder/

view container information

docker inspect

Find container’s IP

docker inspect | grep IPAddress

Make a container an image

docker commit

Map container port to host port

docker run -p :
Category: Containers, Docker | LEAVE A COMMENT
24 July 2022

Install Docker CE on Amazon Linux 2

Here is how to install docker and docker-compose on the (AWS) Amazon Linux 2 OS running on either an EC2 or Lightsail instance.

Let’s begin by opening a console or SSH session to your EC2 or Lightsail instance. You can do this from within your AWS portal or an SSH tool like Putty. The actual “how to connect” to your server is outside the scope of this article.

Once you are connected, let us start by installing any pending updates on your host. 

sudo yum update

Next, we will install Docker. 

sudo yum install docker

Create a new membership group for docker and add the ec2-user to it so you can run all of the docker commands without needing to use the sudo command.

sudo usermod -a -G docker ec2-user
id ec2-user
newgrp docker

Now it’s time to add docker-compose.

wget https://github.com/docker/compose/releases/latest/download/docker-compose-$(uname -s)-$(uname -m) 
sudo mv docker-compose-$(uname -s)-$(uname -m) /usr/local/bin/docker-compose
sudo chmod -v +x /usr/local/bin/docker-compose

Enable the docker service.

sudo systemctl enable docker.service

Start the docker service.

sudo systemctl start docker.service

Verify that the service is running.

sudo systemctl status docker.service

You can check the docker version with this command.

docker version

And lastly you can check the docker-compose version with this command..

docker-compose version

You have now installed docker and docker-compose on Amazon Linux 2.
I am going to leave off with some helpful controls manage docker on your machine.

sudo systemctl start docker.service #start docker
sudo systemctl stop docker.service #stop docker
sudo systemctl restart docker.service #restart docker
sudo systemctl status docker.service #get the status of docker
Category: AWS, Cloud, Containers, Docker, Linux | LEAVE A COMMENT
24 July 2022

Install Docker CE on Ubuntu

So how does someone install Docker on Ubuntu? Let me show you… We’re starting off with a freshly installed Ubuntu 20.04 virtual machine that has been updated but has not had anything additional added to it yet.

We will start with adding some packages that are prerequisites for using the ‘apt’ commands over HTTPS and thus for Docker.

sudo apt install apt-transport-https ca-certificates curl software-properties-common

Next, we’ll add the GPG key for the Official Docker repository.

curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg

Then we’ll add the Docker repo to the sources for APT.

echo "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

We’ll rerun our ‘update’ command.

sudo apt update

And the step everyone was waiting for, installing Docker.

sudo apt install docker-ce

Now we need to allow our user to run Docker commands without always needing to ‘sudo’. We can add the user we are logged in as by using this command.

sudo usermod -aG docker ${USER}

Okay now as an optional step, you can install Docker-Compose. At the time of writing this, it is on v2.7.0. You will want to check their release page and update the command below to the current version number.

mkdir -p ~/.docker/cli-plugins/
curl -SL https://github.com/docker/compose/releases/download/v2.7.0/docker-compose-linux-x86_64 -o ~/.docker/cli-plugins/docker-compose

Then we can set the correct permissions on docker-compose so that it will be executable. 

chmod +x ~/.docker/cli-plugins/docker-compose

Now we can verify our Docker and Docker-Compose are installed by checking their versions with these commands. 

docker compose version
docker version

And that is how you install Docker on your Ubuntu machine

Category: Containers, Docker, Linux, Ubuntu | LEAVE A COMMENT
9 July 2022

Install Docker CE on CentOS 9 Stream

Docker is an operating system virtualization tool that allows us to run applications as containers. In simplest terms, that means you are virtualizing only the application, and not creating an entire virtual machine as you would traditionally do in hypervisors like VMware, Hyper-V, or Nutanix.

Okay, that’s cool… How do we install Docker so we can start to test workloads on it? Well, let me show you how to install Docker on a virtual machine running CentOS 9 Stream.
**While I have not tested to confirm, this Docker installation method should be identical on CentOS 8 Stream, as well as for CentOS 7.x

Let us begin by shifting to Sudo mode by running this command first…

sudo su

Then the first thing to do is remove PodMan as it conflicts with Docker.

dnf -y remove podman runc

The next step is to add the Docker repo.

curl https://download.docker.com/linux/centos/docker-ce.repo -o /etc/yum.repos.d/docker-ce.repo

Update SELinux in regards to the Docker repo.

sed -i -e "s/enabled=1/enabled=0/g" /etc/yum.repos.d/docker-ce.repo

Enable the Docker repo and install Docker.

dnf --enablerepo=docker-ce-stable -y install docker-ce

With Docker installed, it is time to enable it.

systemctl start docker
systemctl enable docker

Let us view what we installed by running these two commands.

rpm -q docker-ce
docker version

Congratulations! You now have Docker installed on your machine.

You’ll probably want to install Docker Compose on your machine too so you can build and run a docker image. You can install it with this simple command.

dnf install docker-compose
Category: CentOS, Containers, Docker, Linux | LEAVE A COMMENT