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1. Debian Docker Image Apt-get
2. Debian Docker Image Location

Docker Official Images Debian is a Linux distribution that's composed entirely of free and open-source software. 500M+ Container Linux PowerPC 64 LE ARM mips64le x86-64 ARM 64 IBM Z 386 Base Images Operating Systems Official Image. This Docker image enhances the Debian image to be run like a VM or LXC container including systemd as init system and other utilities. In addition to systemd cron and anacron will be installed. However, in contrast to the official Debian CD, rsyslog will NOT be installed, as journald should fit most needs.

The Official .NET Docker images are Docker images created and optimized by Microsoft. They are publicly available in the Microsoft repositories on Docker Hub. Each repository can contain multiple images, depending on .NET versions, and depending on the OS and versions (Linux Debian, Linux Alpine, Windows Nano Server, Windows Server Core, etc.).

Since .NET Core 2.1, all the .NET Core or later images, including for ASP.NET Core are available at Docker Hub at the .NET image repository: https://hub.docker.com/_/microsoft-dotnet/.

Since May 2018, Microsoft images are being syndicated in the Microsoft Container Registry. The official catalog is still only available in Docker Hub, and there you'll find the updated address to pull the image.

Most image repositories provide extensive tagging to help you select not just a specific framework version, but also to choose an OS (Linux distribution or Windows version).

.NET and Docker image optimizations for development versus production

When building Docker images for developers, Microsoft focused on the following main scenarios:

• Images used to develop and build .NET apps.

• Images used to run .NET apps.

Why multiple images? When developing, building, and running containerized applications, you usually have different priorities. By providing different images for these separate tasks, Microsoft helps optimize the separate processes of developing, building, and deploying apps.

During development and build

During development, what is important is how fast you can iterate changes, and the ability to debug the changes. The size of the image isn't as important as the ability to make changes to your code and see the changes quickly. Some tools and 'build-agent containers', use the development .NET image (mcr.microsoft.com/dotnet/sdk:5.0) during development and build process. When building inside a Docker container, the important aspects are the elements that are needed to compile your app. This includes the compiler and any other .NET dependencies.

Why is this type of build image important? You don't deploy this image to production. Instead, it's an image that you use to build the content you place into a production image. This image would be used in your continuous integration (CI) environment or build environment when using Docker multi-stage builds.

In production

What is important in production is how fast you can deploy and start your containers based on a production .NET image. Therefore, the runtime-only image based on mcr.microsoft.com/dotnet/aspnet:5.0 is small so that it can travel quickly across the network from your Docker registry to your Docker hosts. The contents are ready to run, enabling the fastest time from starting the container to processing results. In the Docker model, there is no need for compilation from C# code, as there is when you run dotnet build or dotnet publish when using the build container.

In this optimized image, you put only the binaries and other content needed to run the application. For example, the content created by dotnet publish contains only the compiled .NET binaries, images, .js, and .css files. Over time, you will see images that contain pre-jitted (the compilation from IL to native that occurs at runtime) packages.

Although there are multiple versions of the .NET and ASP.NET Core images, they all share one or more layers, including the base layer. Therefore, the amount of disk space needed to store an image is small; it consists only of the delta between your custom image and its base image. The result is that it is quick to pull the image from your registry.

When you explore the .NET image repositories at Docker Hub, you will find multiple image versions classified or marked with tags. These tags help to decide which one to use, depending on the version you need, like those in the following table:

Estimated reading time: 10 minutes

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

Prerequisites

OS requirements

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

• Debian Buster 10 (stable)
• Debian Stretch 9 / Raspbian Stretch

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. The Docker Engine package is now called docker-ce.

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, except for Raspbian.

• 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.This is currently the only approach for Raspbian.

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.

Raspbian users cannot use this method!

For Raspbian, installing using the repository is not yet supported. You mustinstead use the convenience script.

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 yourDebian distribution, such as helium. Sometimes, in a distributionlike BunsenLabs Linux, you might need to change $(lsb_release -cs)to your parent Debian distribution. For example, if you are using BunsenLabs Linux Helium, you could use stretch. Docker does not offer any guarantees on untestedand unsupported Debian distributions.

Install Docker Engine

This procedure works for Debian on x86_64 / amd64, armhf, arm64, and Raspbian.

Debian Docker Image Apt-get

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~debian-stretch .

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/debian/dists/,choose your Debian 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!

Debian Docker Image Location

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:

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.