23-04-2021

Docker Linux Latest Version



Estimated reading time: 15 minutes

Welcome to Docker Desktop! The Docker Desktop for Windows user manual provides information on how to configure and manage your Docker Desktop settings.

For information about Docker Desktop download, system requirements, and installation instructions, see Install Docker Desktop.

Settings

The Docker Desktop menu allows you to configure your Docker settings such as installation, updates, version channels, Docker Hub login,and more.

Amazon Linux provides a stable, secure, and high-performance execution environment for applications. Install Compose on Linux systems. On Linux, you can download the Docker Compose binary from the Compose repository release page on GitHub.Follow the instructions from the link, which involve running the curl command in your terminal to download the binaries.

Docker linux current version

This section explains the configuration options accessible from the Settings dialog.

  1. Open the Docker Desktop menu by clicking the Docker icon in the Notifications area (or System tray):

  2. Select Settings to open the Settings dialog:

General

On the General tab of the Settings dialog, you can configure when to start and update Docker.

  • Start Docker when you log in - Automatically start Docker Desktop upon Windows system login.

  • Expose daemon on tcp://localhost:2375 without TLS - Click this option to enable legacy clients to connect to the Docker daemon. You must use this option with caution as exposing the daemon without TLS can result in remote code execution attacks.

  • Send usage statistics - By default, Docker Desktop sends diagnostics,crash reports, and usage data. This information helps Docker improve andtroubleshoot the application. Clear the check box to opt out. Docker may periodically prompt you for more information.

Resources

The Resources tab allows you to configure CPU, memory, disk, proxies, network, and other resources. Different settings are available for configuration depending on whether you are using Linux containers in WSL 2 mode, Linux containers in Hyper-V mode, or Windows containers.

Advanced

Note

The Advanced tab is only available in Hyper-V mode, because in WSL 2 mode and Windows container mode these resources are managed by Windows. In WSL 2 mode, you can configure limits on the memory, CPU, and swap size allocatedto the WSL 2 utility VM.

Use the Advanced tab to limit resources available to Docker.

CPUs: By default, Docker Desktop is set to use half the number of processorsavailable on the host machine. To increase processing power, set this to ahigher number; to decrease, lower the number.

Memory: By default, Docker Desktop is set to use 2 GB runtime memory,allocated from the total available memory on your machine. To increase the RAM, set this to a higher number. To decrease it, lower the number.

Swap: Configure swap file size as needed. The default is 1 GB.

Disk image size: Specify the size of the disk image.

Disk image location: Specify the location of the Linux volume where containers and images are stored.

You can also move the disk image to a different location. If you attempt to move a disk image to a location that already has one, you get a prompt asking if you want to use the existing image or replace it.

File sharing

Note

The File sharing tab is only available in Hyper-V mode, because in WSL 2 mode and Windows container mode all files are automatically shared by Windows.

Use File sharing to allow local directories on Windows to be shared with Linux containers.This is especially useful forediting source code in an IDE on the host while running and testing the code in a container.Note that configuring file sharing is not necessary for Windows containers, only Linux containers. If a directory is not shared with a Linux container you may get file not found or cannot start service errors at runtime. See Volume mounting requires shared folders for Linux containers.

Docker Linux Latest Version Download

File share settings are:

  • Add a Directory: Click + and navigate to the directory you want to add.

  • Apply & Restart makes the directory available to containers using Docker’sbind mount (-v) feature.

Tips on shared folders, permissions, and volume mounts

  • Share only the directories that you need with the container. File sharing introduces overhead as any changes to the files on the host need to be notified to the Linux VM. Sharing too many files can lead to high CPU load and slow filesystem performance.

  • Shared folders are designed to allow application code to be edited on the host while being executed in containers. For non-code items such as cache directories or databases, the performance will be much better if they are stored in the Linux VM, using a data volume (named volume) or data container.

  • Docker Desktop sets permissions to read/write/execute for users, groups and others 0777 or a+rwx.This is not configurable. See Permissions errors on data directories for shared volumes.

  • Windows presents a case-insensitive view of the filesystem to applications while Linux is case-sensitive. On Linux it is possible to create 2 separate files: test and Test, while on Windows these filenames would actually refer to the same underlying file. This can lead to problems where an app works correctly on a developer Windows machine (where the file contents are shared) but fails when run in Linux in production (where the file contents are distinct). To avoid this, Docker Desktop insists that all shared files are accessed as their original case. Therefore if a file is created called test, it must be opened as test. Attempts to open Test will fail with “No such file or directory”. Similarly once a file called test is created, attempts to create a second file called Test will fail.

Shared folders on demand

Docker Linux Current Version

You can share a folder “on demand” the first time a particular folder is used by a container.

If you run a Docker command from a shell with a volume mount (as shown in theexample below) or kick off a Compose file that includes volume mounts, you get apopup asking if you want to share the specified folder.

You can select to Share it, in which case it is added your Docker Desktop Shared Folders list and available tocontainers. Alternatively, you can opt not to share it by selecting Cancel.

Proxies

Docker Desktop lets you configure HTTP/HTTPS Proxy Settings andautomatically propagates these to Docker. For example, if you set your proxysettings to http://proxy.example.com, Docker uses this proxy when pulling containers.

Your proxy settings, however, will not be propagated into the containers you start.If you wish to set the proxy settings for your containers, you need to defineenvironment variables for them, just like you would do on Linux, for example:

For more information on setting environment variables for running containers,see Set environment variables.

Network

Note

The Network tab is not available in Windows container mode because networking is managed by Windows.

You can configure Docker Desktop networking to work on a virtual private network (VPN). Specify a network address translation (NAT) prefix and subnet mask to enable Internet connectivity.

DNS Server: You can configure the DNS server to use dynamic or static IP addressing.

Note

Some users reported problems connecting to Docker Hub on Docker Desktop. This would manifest as an error when trying to rundocker commands that pull images from Docker Hub that are not alreadydownloaded, such as a first time run of docker run hello-world. If youencounter this, reset the DNS server to use the Google DNS fixed address:8.8.8.8. For more information, seeNetworking issues in Troubleshooting.

Updating these settings requires a reconfiguration and reboot of the Linux VM.

WSL Integration

In WSL 2 mode, you can configure which WSL 2 distributions will have the Docker WSL integration.

By default, the integration will be enabled on your default WSL distribution. To change your default WSL distro, run wsl --set-default <distro name>. (For example, to set Ubuntu as your default WSL distro, run wsl --set-default ubuntu).

You can also select any additional distributions you would like to enable the WSL 2 integration on.

For more details on configuring Docker Desktop to use WSL 2, see Docker Desktop WSL 2 backend.

Docker Engine

The Docker Engine page allows you to configure the Docker daemon to determine how your containers run.

Type a JSON configuration file in the box to configure the daemon settings. For a full list of options, see the Docker Enginedockerd commandline reference.

Click Apply & Restart to save your settings and restart Docker Desktop.

Command Line

On the Command Line page, you can specify whether or not to enable experimental features.

You can toggle the experimental features on and off in Docker Desktop. If you toggle the experimental features off, Docker Desktop uses the current generally available release of Docker Engine.

Experimental features

Experimental features provide early access to future product functionality.These features are intended for testing and feedback only as they may changebetween releases without warning or can be removed entirely from a futurerelease. Experimental features must not be used in production environments.Docker does not offer support for experimental features.

For a list of current experimental features in the Docker CLI, see Docker CLI Experimental features.

Run docker version to verify whether you have enabled experimental features. Experimental modeis listed under Server data. If Experimental is true, then Docker isrunning in experimental mode, as shown here:

Kubernetes

Note

The Kubernetes tab is not available in Windows container mode.

Docker Desktop includes a standalone Kubernetes server that runs on your Windows machince, sothat you can test deploying your Docker workloads on Kubernetes. To enable Kubernetes support and install a standalone instance of Kubernetes running as a Docker container, select Enable Kubernetes. Itunes catalina download.

For more information about using the Kubernetes integration with Docker Desktop, see Deploy on Kubernetes.

Reset

The Restart Docker Desktop and Reset to factory defaults options are now available on the Troubleshoot menu. For information, see Logs and Troubleshooting.

Troubleshoot

Visit our Logs and Troubleshooting guide for more details.

Log on to our Docker Desktop for Windows forum to get help from the community, review current user topics, or join a discussion.

Log on to Docker Desktop for Windows issues on GitHub to report bugs or problems and review community reported issues.

For information about providing feedback on the documentation or update it yourself, see Contribute to documentation.

Switch between Windows and Linux containers

From the Docker Desktop menu, you can toggle which daemon (Linux or Windows)the Docker CLI talks to. Select Switch to Windows containers to use Windowscontainers, or select Switch to Linux containers to use Linux containers(the default).

For more information on Windows containers, refer to the following documentation:

  • Microsoft documentation on Windows containers.

  • Build and Run Your First Windows Server Container (Blog Post)gives a quick tour of how to build and run native Docker Windows containers on Windows 10 and Windows Server 2016 evaluation releases.

  • Getting Started with Windows Containers (Lab)shows you how to use the MusicStoreapplication with Windows containers. The MusicStore is a standard .NET application and,forked here to use containers, is a good example of a multi-container application.

  • To understand how to connect to Windows containers from the local host, seeLimitations of Windows containers for localhost and published ports

Settings dialog changes with Windows containers

When you switch to Windows containers, the Settings dialog only shows those tabs that are active and apply to your Windows containers:

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If you set proxies or daemon configuration in Windows containers mode, theseapply only on Windows containers. If you switch back to Linux containers,proxies and daemon configurations return to what you had set for Linuxcontainers. Your Windows container settings are retained and become availableagain when you switch back.

Dashboard

The Docker Desktop Dashboard enables you to interact with containers and applications and manage the lifecycle of your applications directly from your machine. The Dashboard UI shows all running, stopped, and started containers with their state. It provides an intuitive interface to perform common actions to inspect and manage containers and Docker Compose applications. For more information, see Docker Desktop Dashboard.

Docker Hub

Select Sign in /Create Docker ID from the Docker Desktop menu to access your Docker Hub account. Once logged in, you can access your Docker Hub repositories directly from the Docker Desktop menu.

For more information, refer to the following Docker Hub topics:

Two-factor authentication

Docker Desktop enables you to sign into Docker Hub using two-factor authentication. Two-factor authentication provides an extra layer of security when accessing your Docker Hub account.

You must enable two-factor authentication in Docker Hub before signing into your Docker Hub account through Docker Desktop. For instructions, see Enable two-factor authentication for Docker Hub.

After you have enabled two-factor authentication:

  1. Go to the Docker Desktop menu and then select Sign in / Create Docker ID.

  2. Enter your Docker ID and password and click Sign in.

  3. After you have successfully signed in, Docker Desktop prompts you to enter the authentication code. Enter the six-digit code from your phone and then click Verify.

After you have successfully authenticated, you can access your organizations and repositories directly from the Docker Desktop menu.

Adding TLS certificates

You can add trusted Certificate Authorities (CAs) to your Docker daemon to verify registry server certificates, and client certificates, to authenticate to registries.

How do I add custom CA certificates?

Docker Desktop supports all trusted Certificate Authorities (CAs) (root orintermediate). Docker recognizes certs stored under Trust RootCertification Authorities or Intermediate Certification Authorities.

Docker Desktop creates a certificate bundle of all user-trusted CAs based onthe Windows certificate store, and appends it to Moby trusted certificates. Therefore, if an enterprise SSL certificate is trusted by the user on the host, it is trusted by Docker Desktop.

To learn more about how to install a CA root certificate for the registry, seeVerify repository client with certificatesin the Docker Engine topics.

How do I add client certificates?

You can add your client certificatesin ~/.docker/certs.d/<MyRegistry>:<Port>/client.cert and~/.docker/certs.d/<MyRegistry>:<Port>/client.key. You do not need to push your certificates with git commands.

When the Docker Desktop application starts, it copies the~/.docker/certs.d folder on your Windows system to the /etc/docker/certs.ddirectory on Moby (the Docker Desktop virtual machine running on Hyper-V).

You need to restart Docker Desktop after making any changes to the keychainor to the ~/.docker/certs.d directory in order for the changes to take effect.

The registry cannot be listed as an insecure registry (seeDocker Daemon). Docker Desktop ignorescertificates listed under insecure registries, and does not send clientcertificates. Commands like docker run that attempt to pull from the registryproduce error messages on the command line, as well as on the registry.

To learn more about how to set the client TLS certificate for verification, seeVerify repository client with certificatesin the Docker Engine topics.

Where to go next

Docker Linux Latest Version Latest

  • Try out the walkthrough at Get Started.

  • Dig in deeper with Docker Labs example walkthroughs and source code.

  • Refer to the Docker CLI Reference Guide.

windows, edge, tutorial, run, docker, local, machine

Unix Latest Version

This blog post is the result of collaboration between Arm and Docker. Special thanks to Jason Andrews @ Arm for creating much of the original content.

Arm and Docker announced a strategic partnership earlier this year to unify software development and deployment across a diverse set of devices, from IoT endpoints to the edge of the network, and into the heart of the data center. Docker has simplified enterprise software development and deployment leading to true multi-platform portability and cost savings on Arm-based cloud instances. Even more exciting is how Docker is changing the way embedded software is being developed and deployed.

Traditionally embedded Linux software applications have been created by cross-compiling and copying files to an embedded target board. There are various methods to automate this process, but it has generally been unchanged since the 1990’s when non-x86 embedded possessors running Linux appeared. Docker stands to make the first significant change to the embedded Linux application developer’s workflow.

This article continues from Building Multi-Arch Images for Arm and x86 with Docker Desktop and shows the same capabilities in Linux. Although Windows and Mac support is great, the majority of software developers targeting embedded Linux systems also do their development work on Linux. The multi-architecture support in Docker also greatly simplifies embedded Linux application development and deployment.

If you are doing software development on x86 Linux machines and want to create Docker images that run on Arm servers or Arm embedded and IoT devices, this article will be helpful to understand the process and the different ways to do it.

Let’s see how to use Docker for Arm software development using the new buildx feature on Linux to create multi-architecture container images and run them. I’m using Ubuntu 18.04, but the same info applies to most any Linux distribution.

Install Docker

Installing Docker on Linux takes just a few commands. More installation info is available in the Docker Documentation.

If you already have an older version of Docker, make sure to uninstall it first. Using buildx requires Docker 19.03 and today the best way to get this is using the test instead of the stable version.

Add the current user to the docker group to avoid needing sudo to run the docker command:

Make sure to log out and back in again. Now test the install with a quick hello-world run.

Use the docker version command to check the running version:

Install buildx for multi-architecture image builds

There are three options to get buildx on Linux:

  • Use buildx directly from the test channel version of Docker
  • Download a binary release of buildx and copy it to the $HOME/.docker directory
  • Download, build, and install buildx from github.com
Use buildx from Docker test channel

The test version of Docker already has buildx included. The only thing needed is to set the environment variable to enable experimental command line features.

Download a binary release

Another way to get buildx is to download a binary release from github and put in the .docker/cli-plugins directory.

For example, download the buildx for Linux amd64 with a browser from: https://github.com/docker/buildx/releases/tag/v0.2.0

Then copy it to the cli-plugins/ directory (create it first if necessary):

Download, build, and install buildx

Because buildx is a new command and documentation is still catching up, githubis a good place to read more information about how buildx works.

To get buildx from github use the commands:

To confirm buildx is now installed run the help and the version command.

Register Arm executables to run on x64 machines

Install the qemu instruction emulation to register Arm executables to run on the x86 machine. For best results, the latest qemu image should be used. If an older qemu is used some application may not work correctly on the x86 hardware.

To verify the qemu handlers are registered properly, run the following and make sure the first line of the output is “enabled”. Note that the handler registration doesn’t survive a reboot, but could be added to the system start-up scripts.

Create a multi-architecture build instance

Setup a new builder instance to create multi-architecture images.

Try buildx

There are multiple examples of buildx available, but here is a simple one for C programmers! Create a file named hello.c with this code:

Jul 05, 2018 Docker is an application that simplifies the process of managing application processes in containers. In this tutorial, you'll install and use Docker Community Edition (CE) on Ubuntu 18.04. Docker update ubuntu. Nov 07, 2019 When running docker desktop version 2.1.5.0 (40323) on: OS Name: Microsoft Windows 10 Pro OS Version: 10.0.19013 N/A Build 19013 Eben though WSL 2 based engine is enabled in Settings/General docker container run hello-world on Ubuntu rep. This is running a Docker Container using the official Ubuntu 14.04 The end result will be the same as this QA once I can get that command installed. New to Ubuntu and such, trying to get a docker container to update certs that i am linking in using -v.

Here is a Docker file to build and run it. Let’s get used to using multi-stage Docker files as it will be common for deploying embedded applications. Create a Dockerfile with the following:

Now, use buildx to build for multiple architectures and push to Docker hub.

Use docker login first if needed and substitute your own Hub account.

Run using the sha from the manifest and see the output from uname as armv7l, aarch64, and x86_64:

Next steps

As we have seen, building multi-architecture containers can be created with buildx in the same way as with Docker Desktop for Mac and Windows. Give it a try for yourself and start making the transition to multi-architecture Docker images today.

Further Reading