Install Docker Community Ubuntu

#deb arch=amd64 focal stable Press Ctrl+o to save, ctrl+x to close. Run the following command to install docker: sudo apt update && sudo apt install docker-ce docker-ce-cli containerd.io Running the above command will successfully install docker. Install from a package 🔗 Go to, choose your Ubuntu version, then browse to pool/stable/, choose. Install Docker Engine, changing the path below to the path where you downloaded the Docker package. Verify that Docker Engine is.

Docker Community Edition Overview

Docker is a tool designed to create, deploy, and run applications using containers.

Containers allow to pack an application with all requirements necessary, such as libraries and other dependencies, and ship it out as one package.

This ensures that an application can run on any Linux machine, regardless of the specific settings of the host machine, which might be different from the development environment.

Requirements:

• You have an account and are logged into console.scaleway.com
• You have an Ubuntu Bionic server
• You have configured your SSH Key
• You have sudo privileges or access to the root user.

Installing Docker Community Edition

Docker Community Edition (CE) is the classic open source Docker environment.

1 . Before installing the latest version of Docker on your server, make sure to remove any old version that might have already been installed

Note:apt-get might report that none of these packages is installed. This is fine, and you can continue with the installation.

2 . Update the apt package cache to make sure all required software is referenced

3 . As Docker uses HTTPS for their repository, install the required packages so apt can download them via a secure connection

4 . Add Docker's official SSH key to apt

5 . Verify the fingerprint of the key (9DC8 5822 9FC7 DD38 854A E2D8 8D81 803C 0EBF CD88), by looking at the last 8 characters

6 . Add the repository for the stable version of Docker. For a x86_64 based server, use the following command

Note: On ARM-based servers, replace amd64 either with armhf or arm64, depending on the architecture of the CPU.

7 . Update the apt packet cache

8 . Install the latest version of Docker

9 . Verify that Docker has been installed by running the Hello World container

Managing Docker as a non-root user

The docker daemon always runs as root user and binds to a Unix socket instead of a TCP port. This Unix socket is owned by the root user by default, and other users can only access it by using sudo.

If you don't want to use sudo with the docker command, create a Unix group called docker and add users to it. The daemon makes the ownership of the Unix socket read/writable by the docker group when it starts.

Warning: Adding users to the docker group grants privileges equivalent to the root user. This can be a security risk. For more information read about Docker Daemon Attack Surface

1 . Create the docker group.

2 . Add your user to the docker group.

3 . To re-evaluate your group membership, log out and log back in.

If you are executing these commands on a virtual machine, it may be necessary to restart the VM for the changes to take effect.

4 . Verify that you can run docker commands without sudo by downloading a test-image and running it in a container

If you were using docker CLI using sudo before adding your user to the docker group, you might encounter an error message, telling you that your ~/.docker/ directory was created with incorrect permissions:

This problem can either be fixed by removing the ~/.docker/ directory or by changing the ownership and permissions using the following commands

Important: If you remove the directory, it will be created again automatically when you rerun Docker. Any custom settings will be lost.

Configuring Docker to start on boot

Ubuntu uses systemd to manage services. Docker comes with a pre-built systemd configuration, and you can enable the service to start automatically on boot

If you don't want Docker to start automatically, disable it in the same way

Building your first container

In the past, all software dependencies required to run your application had to be installed on either the physical machine or a VM.

Managing all these machines can become quite hard and if you ship your application to one of your customers (s)he might have a different system configuration and your application might not work as expected.

Let's say you want to develop a Python web application. Docker allows you to grab a portable Python runtime as an image, no installation necessary.

You develop your application, and your build can include the base Python image right alongside your app code, ensuring that your app, its dependencies, and the runtime, perfectly designed for each other are shipped together.

Creating the Dockerfile

Portable images are defined in a file called Dockerfile and define what goes on in the environment inside your container.

Resources of the server (like network interfaces or disk drives) are virtualized inside this environment, and it is isolated from the rest of your system.

This means you have to map ports to the outside world and define precisely about what files you want to copy into that environment.

Thanks to this, you can expect that the build of your application defined in the Dockerfile behaves precisely the same, no matter wherever it runs.

Building your first container, running a small web application.

1 . Create a new directory to develop your environment

2 . Enter into the directory

3 . Create a new file, called Dockerfile, copy & paste the following content into it and save the file

Creating the Application

Now as you have created your Dockerfile, it is time to create your application. Open a text editor, copy paste the following content and save the file as app.py.

Building the Container

Now as you have created a Dockerfile and the application, it is time to build the container.

1 . Check if you are in the correct directory and that both files are present

2 . Build the image. The -t tag allows you to set a friendly name for the image:

The application will recover the environment variable we have set in the dockerfile and display the containers host name.

Docker will now download the python base image and process the tasks defined in the Dockerfile:

Your image is now available in your local docker registry:

Running the Application

Now it is time to run your application for the first time.

Use the -p option to map the port 4000 of your computer to port 80 of the container:

You will see a message similar to the following:

You can notice that the application is running on port 80.

Remember, this is the internal port of your container and can reach the application by typing http://localhost:4000 in the address bar of your browser:

The application displays the internal hostname of the container and retrieves the word 'World' from the environment variable that you have set in the Dockerfile.

Sharing the Application

Docker lets you easily ship your image to a registry to share it with others.

We use the public docker registry in this example, but you can also set up a private registry to distribute the image on your infrastructure.

It is required to have a Docker account for this part of the tutorial. If you don't have one, you can create an account at hub.docker.com.

1 . Login into the Docker registry:

To associate a local image with a repository on a registry, you have to use the notation username/repository:tag.

The tag is not mandatory, but recommended as it is the mechanism that registries use to give Docker images a version.

Docker Community Install Ubuntu

To push your image you have to run docker tag with your username, repository, and tag, so your image uploads to the desired destination.

2 . Tag the image:

3 . Publish your image:

Once the image has been pushed to Docker Hub it will be publicly available and you can see the image with its pull command in your account.

Pulling and running an Image from a Remote Repository

As your image is available on the Docker Hub now, you can run it from everywhere

If the image is not available yet on the local machine, Docker will download it from the registry.

No matter on which machine you run it, it will always run in the same environment that you have configured when you have built the image.

Estimated reading time: 10 minutes

To get started with Docker Engine on Ubuntu, make sure youmeet the prerequisites, theninstall Docker.

Prerequisites

OS requirements

To install Docker Engine, you need the 64-bit version of one of these Ubuntuversions:

• Ubuntu Groovy 20.10
• Ubuntu Focal 20.04 (LTS)
• Ubuntu Bionic 18.04 (LTS)
• Ubuntu Xenial 16.04 (LTS)

Docker Engine is supported on x86_64 (or amd64), armhf, and arm64 architectures.

Uninstall old versions

Older versions of Docker were called docker, docker.io, or docker-engine.If these are installed, uninstall them:

It's OK if apt-get reports that none of these packages are installed.

The contents of /var/lib/docker/, including images, containers, volumes, andnetworks, are preserved. If you do not need to save your existing data, and want tostart with a clean installation, refer to the uninstall Docker Enginesection at the bottom of this page.

Supported storage drivers

Docker Engine on Ubuntu supports overlay2, aufs and btrfs storage drivers.

Docker Engine uses the overlay2 storage driver by default. If you need to useaufs instead, you need to configure it manually.See use the AUFS storage driver

Installation methods

You can install Docker Engine in different ways, depending on your needs:

• Most usersset up Docker's repositories and installfrom them, for ease of installation and upgrade tasks. This is therecommended approach.

• Some users download the DEB package andinstall it manually and manageupgrades completely manually. This is useful in situations such as installingDocker on air-gapped systems with no access to the internet.

• In testing and development environments, some users choose to use automatedconvenience scripts to install Docker.

Install using the repository

Before you install Docker Engine for the first time on a new host machine, you needto set up the Docker repository. Afterward, you can install and update Dockerfrom the repository.

Set up the repository

1. Update the apt package index and install packages to allow apt to use arepository over HTTPS:

2. Add Docker's official GPG key:

3. Use the following command to set up the stable repository. To add thenightly or test repository, add the word nightly or test (or both)after the word stable in the commands below. Learn about nightly and test channels.

   Note: The lsb_release -cs sub-command below returns the name of yourUbuntu distribution, such as xenial. Sometimes, in a distributionlike Linux Mint, you might need to change $(lsb_release -cs)to your parent Ubuntu distribution. For example, if you are using Linux Mint Tessa, you could use bionic. Docker does not offer any guarantees on untestedand unsupported Ubuntu distributions.

Install Docker Engine

1. Update the apt package index, and install the latest version of DockerEngine and containerd, or go to the next step to install a specific version:

   Got multiple Docker repositories?

   If you have multiple Docker repositories enabled, installingor updating without specifying a version in the apt-get install orapt-get update command always installs the highest possible version,which may not be appropriate for your stability needs.

2. To install a specific version of Docker Engine, list the available versionsin the repo, then select and install:

   a. List the versions available in your repo:

   b. Install a specific version using the version string from the second column, for example, 5:18.09.1~3-0~ubuntu-xenial.

3. Verify that Docker Engine is installed correctly by running the hello-worldimage.

   This command downloads a test image and runs it in a container. When thecontainer runs, it prints an informational message and exits.

Docker Engine is installed and running. The docker group is created but no usersare added to it. You need to use sudo to run Docker commands.Continue to Linux postinstall to allow non-privilegedusers to run Docker commands and for other optional configuration steps.

Upgrade Docker Engine

To upgrade Docker Engine, first run sudo apt-get update, then follow theinstallation instructions, choosing the newversion you want to install.

Install from a package

If you cannot use Docker's repository to install Docker Engine, you can download the.deb file for your release and install it manually. You need to downloada new file each time you want to upgrade Docker.

1. Go to https://download.docker.com/linux/ubuntu/dists/,choose your Ubuntu version, then browse to pool/stable/, choose amd64,armhf, or arm64, and download the .deb file for the Docker Engineversion you want to install.

   Note: To install a nightly or test (pre-release) package,change the word stable in the above URL to nightly or test.Learn about nightly and test channels.

2. Install Docker Engine, changing the path below to the path where you downloadedthe Docker package.

   The Docker daemon starts automatically.

3. Verify that Docker Engine is installed correctly by running the hello-worldimage.

   This command downloads a test image and runs it in a container. When thecontainer runs, it prints an informational message and exits.

Docker Engine is installed and running. The docker group is created but no usersare added to it. You need to use sudo to run Docker commands.Continue to Post-installation steps for Linux to allownon-privileged users to run Docker commands and for other optional configurationsteps.

Upgrade Docker Engine

To upgrade Docker Engine, download the newer package file and repeat theinstallation procedure, pointing to the new file.

Install using the convenience script

Docker provides convenience scripts at get.docker.comand test.docker.com for installing edge andtesting versions of Docker Engine - Community into development environments quickly andnon-interactively. The source code for the scripts is in thedocker-install repository.Using these scripts is not recommended for productionenvironments, and you should understand the potential risks before you usethem:

• The scripts require root or sudo privileges to run. Therefore,you should carefully examine and audit the scripts before running them.
• The scripts attempt to detect your Linux distribution and version andconfigure your package management system for you. In addition, the scripts donot allow you to customize any installation parameters. This may lead to anunsupported configuration, either from Docker's point of view or from your ownorganization's guidelines and standards.
• The scripts install all dependencies and recommendations of the packagemanager without asking for confirmation. This may install a large number ofpackages, depending on the current configuration of your host machine.
• The script does not provide options to specify which version of Docker to install,and installs the latest version that is released in the 'edge' channel.
• Do not use the convenience script if Docker has already been installed on thehost machine using another mechanism.

This example uses the script at get.docker.com toinstall the latest release of Docker Engine - Community on Linux. To install the latesttesting version, use test.docker.com instead. Ineach of the commands below, replace each occurrence of get with test.

Warning:

Always examine scripts downloaded from the internet beforerunning them locally.

If you would like to use Docker as a non-root user, you should now consideradding your user to the 'docker' group with something like:

Remember to log out and back in for this to take effect!

Install Docker Community Ubuntu Windows 10

Warning:

Adding a user to the 'docker' group grants them the ability to run containerswhich can be used to obtain root privileges on the Docker host. Refer toDocker Daemon Attack Surfacefor more information.

Docker Engine - Community is installed. It starts automatically on DEB-based distributions. OnRPM-based distributions, you need to start it manually using the appropriatesystemctl or service command. As the message indicates, non-root users can'trun Docker commands by default.

Note:

5 . Verify the fingerprint of the key (9DC8 5822 9FC7 DD38 854A E2D8 8D81 803C 0EBF CD88), by looking at the last 8 characters

6 . Add the repository for the stable version of Docker. For a x86_64 based server, use the following command

Note: On ARM-based servers, replace amd64 either with armhf or arm64, depending on the architecture of the CPU.

7 . Update the apt packet cache

8 . Install the latest version of Docker

9 . Verify that Docker has been installed by running the Hello World container

Managing Docker as a non-root user

The docker daemon always runs as root user and binds to a Unix socket instead of a TCP port. This Unix socket is owned by the root user by default, and other users can only access it by using sudo.

If you don't want to use sudo with the docker command, create a Unix group called docker and add users to it. The daemon makes the ownership of the Unix socket read/writable by the docker group when it starts.

Warning: Adding users to the docker group grants privileges equivalent to the root user. This can be a security risk. For more information read about Docker Daemon Attack Surface

1 . Create the docker group.

2 . Add your user to the docker group.

3 . To re-evaluate your group membership, log out and log back in.

If you are executing these commands on a virtual machine, it may be necessary to restart the VM for the changes to take effect.

4 . Verify that you can run docker commands without sudo by downloading a test-image and running it in a container

If you were using docker CLI using sudo before adding your user to the docker group, you might encounter an error message, telling you that your ~/.docker/ directory was created with incorrect permissions:

This problem can either be fixed by removing the ~/.docker/ directory or by changing the ownership and permissions using the following commands

Important: If you remove the directory, it will be created again automatically when you rerun Docker. Any custom settings will be lost.

Configuring Docker to start on boot

Ubuntu uses systemd to manage services. Docker comes with a pre-built systemd configuration, and you can enable the service to start automatically on boot

If you don't want Docker to start automatically, disable it in the same way

Building your first container

In the past, all software dependencies required to run your application had to be installed on either the physical machine or a VM.

Managing all these machines can become quite hard and if you ship your application to one of your customers (s)he might have a different system configuration and your application might not work as expected.

Let's say you want to develop a Python web application. Docker allows you to grab a portable Python runtime as an image, no installation necessary.

You develop your application, and your build can include the base Python image right alongside your app code, ensuring that your app, its dependencies, and the runtime, perfectly designed for each other are shipped together.

Creating the Dockerfile

Portable images are defined in a file called Dockerfile and define what goes on in the environment inside your container.

Resources of the server (like network interfaces or disk drives) are virtualized inside this environment, and it is isolated from the rest of your system.

This means you have to map ports to the outside world and define precisely about what files you want to copy into that environment.

Thanks to this, you can expect that the build of your application defined in the Dockerfile behaves precisely the same, no matter wherever it runs.

Building your first container, running a small web application.

1 . Create a new directory to develop your environment

2 . Enter into the directory

3 . Create a new file, called Dockerfile, copy & paste the following content into it and save the file

Creating the Application

Now as you have created your Dockerfile, it is time to create your application. Open a text editor, copy paste the following content and save the file as app.py.

Building the Container

Now as you have created a Dockerfile and the application, it is time to build the container.

1 . Check if you are in the correct directory and that both files are present

2 . Build the image. The -t tag allows you to set a friendly name for the image:

The application will recover the environment variable we have set in the dockerfile and display the containers host name.

Docker will now download the python base image and process the tasks defined in the Dockerfile:

Your image is now available in your local docker registry:

Running the Application

Now it is time to run your application for the first time.

Use the -p option to map the port 4000 of your computer to port 80 of the container:

You will see a message similar to the following:

You can notice that the application is running on port 80.

Remember, this is the internal port of your container and can reach the application by typing http://localhost:4000 in the address bar of your browser:

The application displays the internal hostname of the container and retrieves the word 'World' from the environment variable that you have set in the Dockerfile.

Sharing the Application

Docker lets you easily ship your image to a registry to share it with others.

We use the public docker registry in this example, but you can also set up a private registry to distribute the image on your infrastructure.

It is required to have a Docker account for this part of the tutorial. If you don't have one, you can create an account at hub.docker.com.

1 . Login into the Docker registry:

To associate a local image with a repository on a registry, you have to use the notation username/repository:tag.

The tag is not mandatory, but recommended as it is the mechanism that registries use to give Docker images a version.

Docker Community Install Ubuntu

To push your image you have to run docker tag with your username, repository, and tag, so your image uploads to the desired destination.

2 . Tag the image:

3 . Publish your image:

Once the image has been pushed to Docker Hub it will be publicly available and you can see the image with its pull command in your account.

Pulling and running an Image from a Remote Repository

As your image is available on the Docker Hub now, you can run it from everywhere

If the image is not available yet on the local machine, Docker will download it from the registry.

No matter on which machine you run it, it will always run in the same environment that you have configured when you have built the image.

Estimated reading time: 10 minutes

To get started with Docker Engine on Ubuntu, make sure youmeet the prerequisites, theninstall Docker.

Prerequisites

OS requirements

To install Docker Engine, you need the 64-bit version of one of these Ubuntuversions:

• Ubuntu Groovy 20.10
• Ubuntu Focal 20.04 (LTS)
• Ubuntu Bionic 18.04 (LTS)
• Ubuntu Xenial 16.04 (LTS)

Docker Engine is supported on x86_64 (or amd64), armhf, and arm64 architectures.

Uninstall old versions

Older versions of Docker were called docker, docker.io, or docker-engine.If these are installed, uninstall them:

It's OK if apt-get reports that none of these packages are installed.

The contents of /var/lib/docker/, including images, containers, volumes, andnetworks, are preserved. If you do not need to save your existing data, and want tostart with a clean installation, refer to the uninstall Docker Enginesection at the bottom of this page.

Supported storage drivers

Docker Engine on Ubuntu supports overlay2, aufs and btrfs storage drivers.

Docker Engine uses the overlay2 storage driver by default. If you need to useaufs instead, you need to configure it manually.See use the AUFS storage driver

Installation methods

You can install Docker Engine in different ways, depending on your needs:

• Most usersset up Docker's repositories and installfrom them, for ease of installation and upgrade tasks. This is therecommended approach.

• Some users download the DEB package andinstall it manually and manageupgrades completely manually. This is useful in situations such as installingDocker on air-gapped systems with no access to the internet.

• In testing and development environments, some users choose to use automatedconvenience scripts to install Docker.

Install using the repository

Before you install Docker Engine for the first time on a new host machine, you needto set up the Docker repository. Afterward, you can install and update Dockerfrom the repository.

Set up the repository

1. Update the apt package index and install packages to allow apt to use arepository over HTTPS:

2. Add Docker's official GPG key:

3. Use the following command to set up the stable repository. To add thenightly or test repository, add the word nightly or test (or both)after the word stable in the commands below. Learn about nightly and test channels.

   Note: The lsb_release -cs sub-command below returns the name of yourUbuntu distribution, such as xenial. Sometimes, in a distributionlike Linux Mint, you might need to change $(lsb_release -cs)to your parent Ubuntu distribution. For example, if you are using Linux Mint Tessa, you could use bionic. Docker does not offer any guarantees on untestedand unsupported Ubuntu distributions.

Install Docker Engine

1. Update the apt package index, and install the latest version of DockerEngine and containerd, or go to the next step to install a specific version:

   Got multiple Docker repositories?

   If you have multiple Docker repositories enabled, installingor updating without specifying a version in the apt-get install orapt-get update command always installs the highest possible version,which may not be appropriate for your stability needs.

2. To install a specific version of Docker Engine, list the available versionsin the repo, then select and install:

   a. List the versions available in your repo:

   b. Install a specific version using the version string from the second column, for example, 5:18.09.1~3-0~ubuntu-xenial.

3. Verify that Docker Engine is installed correctly by running the hello-worldimage.

   This command downloads a test image and runs it in a container. When thecontainer runs, it prints an informational message and exits.

Docker Engine is installed and running. The docker group is created but no usersare added to it. You need to use sudo to run Docker commands.Continue to Linux postinstall to allow non-privilegedusers to run Docker commands and for other optional configuration steps.

Upgrade Docker Engine

To upgrade Docker Engine, first run sudo apt-get update, then follow theinstallation instructions, choosing the newversion you want to install.

Install from a package

If you cannot use Docker's repository to install Docker Engine, you can download the.deb file for your release and install it manually. You need to downloada new file each time you want to upgrade Docker.

1. Go to https://download.docker.com/linux/ubuntu/dists/,choose your Ubuntu version, then browse to pool/stable/, choose amd64,armhf, or arm64, and download the .deb file for the Docker Engineversion you want to install.

   Note: To install a nightly or test (pre-release) package,change the word stable in the above URL to nightly or test.Learn about nightly and test channels.

2. Install Docker Engine, changing the path below to the path where you downloadedthe Docker package.

   The Docker daemon starts automatically.

3. Verify that Docker Engine is installed correctly by running the hello-worldimage.

   This command downloads a test image and runs it in a container. When thecontainer runs, it prints an informational message and exits.

Docker Engine is installed and running. The docker group is created but no usersare added to it. You need to use sudo to run Docker commands.Continue to Post-installation steps for Linux to allownon-privileged users to run Docker commands and for other optional configurationsteps.

Upgrade Docker Engine

To upgrade Docker Engine, download the newer package file and repeat theinstallation procedure, pointing to the new file.

Install using the convenience script

Docker provides convenience scripts at get.docker.comand test.docker.com for installing edge andtesting versions of Docker Engine - Community into development environments quickly andnon-interactively. The source code for the scripts is in thedocker-install repository.Using these scripts is not recommended for productionenvironments, and you should understand the potential risks before you usethem:

• The scripts require root or sudo privileges to run. Therefore,you should carefully examine and audit the scripts before running them.
• The scripts attempt to detect your Linux distribution and version andconfigure your package management system for you. In addition, the scripts donot allow you to customize any installation parameters. This may lead to anunsupported configuration, either from Docker's point of view or from your ownorganization's guidelines and standards.
• The scripts install all dependencies and recommendations of the packagemanager without asking for confirmation. This may install a large number ofpackages, depending on the current configuration of your host machine.
• The script does not provide options to specify which version of Docker to install,and installs the latest version that is released in the 'edge' channel.
• Do not use the convenience script if Docker has already been installed on thehost machine using another mechanism.

This example uses the script at get.docker.com toinstall the latest release of Docker Engine - Community on Linux. To install the latesttesting version, use test.docker.com instead. Ineach of the commands below, replace each occurrence of get with test.

Warning:

Always examine scripts downloaded from the internet beforerunning them locally.

If you would like to use Docker as a non-root user, you should now consideradding your user to the 'docker' group with something like:

Remember to log out and back in for this to take effect!

Install Docker Community Ubuntu Windows 10

Warning:

Adding a user to the 'docker' group grants them the ability to run containerswhich can be used to obtain root privileges on the Docker host. Refer toDocker Daemon Attack Surfacefor more information.

Docker Engine - Community is installed. It starts automatically on DEB-based distributions. OnRPM-based distributions, you need to start it manually using the appropriatesystemctl or service command. As the message indicates, non-root users can'trun Docker commands by default.

Note:

To install Docker without root privileges, seeRun the Docker daemon as a non-root user (Rootless mode).

Upgrade Docker after using the convenience script

If you installed Docker using the convenience script, you should upgrade Dockerusing your package manager directly. There is no advantage to re-running theconvenience script, and it can cause issues if it attempts to re-addrepositories which have already been added to the host machine.

Uninstall Docker Engine

1. Uninstall the Docker Engine, CLI, and Containerd packages:

2. Images, containers, volumes, or customized configuration files on your hostare not automatically removed. To delete all images, containers, andvolumes:

Install Docker In Ubuntu 20

You must delete any edited configuration files manually.

Next steps

• Continue to Post-installation steps for Linux.
• Review the topics in Develop with Docker to learn how to build new applications using Docker.