Answer Guruji(8920128728): Get started with Docker for Windows

Welcome to Docker Desktop!

This page contains information about Docker Desktop Community (Stable and Edge) releases.

Docker is a full development platform for creating containerized applications. Docker Desktop is the best way to get started with Docker on Windows.

See Install Docker Desktop for information on system requirements and Stable and Edge channels.

Test your installation

Open a terminal window (Command Prompt or PowerShell, but not PowerShell ISE).
Run docker --version to ensure that you have a supported version of Docker:
```
> docker --version

Docker version 19.03.1
```

Pull the hello-world image from Docker Hub and run a container:

> docker run hello-world

docker : Unable to find image 'hello-world:latest' locally
...

latest:
Pulling from library/hello-world
ca4f61b1923c:
Pulling fs layer
ca4f61b1923c:
Download complete
ca4f61b1923c:
Pull complete
Digest: sha256:97ce6fa4b6cdc0790cda65fe7290b74cfebd9fa0c9b8c38e979330d547d22ce1
Status: Downloaded newer image for hello-world:latest

Hello from Docker!
This message shows that your installation appears to be working correctly.
...

List the hello-world image that was downloaded from Docker Hub:
```
> docker image ls
```
List the hello-world container (that exited after displaying “Hello from Docker!”):
```
> docker container ls --all
```

Explore the Docker help pages by running some help commands:

> docker --help
> docker container --help
> docker container ls --help
> docker run --help

Explore the application

In this section, we demonstrate the ease and power of Dockerized applications by running something more complex, such as an OS and a webserver.

Pull an image of the Ubuntu OS and run an interactive terminal inside the spawned container:

 > docker run --interactive --tty ubuntu bash

 docker : Unable to find image 'ubuntu:latest' locally
 ...

 latest:
 Pulling from library/ubuntu
 22dc81ace0ea:
 Pulling fs layer
 1a8b3c87dba3:
 Pulling fs layer
 91390a1c435a:
 Pulling fs layer
 ...
 Digest: sha256:e348fbbea0e0a0e73ab0370de151e7800684445c509d46195aef73e090a49bd6
 Status: Downloaded newer image for ubuntu:latest

Do not use PowerShell ISE

Interactive terminals do not work in PowerShell ISE (but they do in PowerShell). See docker/for-win/issues/223.

You are in the container. At the root # prompt, check the hostname of the container:
```
 root@8aea0acb7423:/# hostname
 8aea0acb7423
```
Notice that the hostname is assigned as the container ID (and is also used in the prompt).
Exit the shell with the exit command (which also stops the container):
```
 root@8aea0acb7423:/# exit
 >
```

List containers with the --all option (because no containers are running).

The hello-world container (randomly named, relaxed_sammet) stopped after displaying its message. The ubuntu container (randomly named, laughing_kowalevski) stopped when you exited the container.

 > docker container ls --all

 CONTAINER ID    IMAGE          COMMAND     CREATED          STATUS                      PORTS    NAMES
 8aea0acb7423    ubuntu         "bash"      2 minutes ago    Exited (0) 2 minutes ago             laughing_kowalevski
 45f77eb48e78    hello-world    "/hello"    3 minutes ago    Exited (0) 3 minutes ago             relaxed_sammet

Pull and run a Dockerized nginx web server that we name, webserver:

 > docker run --detach --publish 80:80 --name webserver nginx

 Unable to find image 'nginx:latest' locally
 latest: Pulling from library/nginx

 fdd5d7827f33: Pull complete
 a3ed95caeb02: Pull complete
 716f7a5f3082: Pull complete
 7b10f03a0309: Pull complete
 Digest: sha256:f6a001272d5d324c4c9f3f183e1b69e9e0ff12debeb7a092730d638c33e0de3e
 Status: Downloaded newer image for nginx:latest
 dfe13c68b3b86f01951af617df02be4897184cbf7a8b4d5caf1c3c5bd3fc267f

Point your web browser at http://localhost to display the nginx start page. (You don’t need to append :80 because you specified the default HTTP port in the docker command.)

List only your running containers:

 > docker container ls

 CONTAINER ID    IMAGE    COMMAND                   CREATED          STATUS          PORTS                 NAMES
 0e788d8e4dfd    nginx    "nginx -g 'daemon of…"    2 minutes ago    Up 2 minutes    0.0.0.0:80->80/tcp    webserver

Stop the running nginx container by the name we assigned it, webserver:
```
 >  docker container stop webserver
```
Remove all three containers by their names -- the latter two names will differ for you:
```
 > docker container rm webserver laughing_kowalevski relaxed_sammet
```

Docker Settings dialog

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

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

Open the Docker Desktop menu by clicking the Docker icon in the Notifications area (or System tray):
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.
Automatically check for updates - By default, Docker Desktop automatically checks for updates and notifies you when an update is available. Click OK to accept and install updates (or cancel to keep the current version). You can manually update by choosing Check for Updates from the main Docker menu.
Send usage statistics - By default, Docker Desktop sends diagnostics, crash reports, and usage data. This information helps Docker improve and troubleshoot the application. Clear the check box to opt out. Docker may periodically prompt you for more information.
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.

Shared drives

Share your local drives (volumes) with Docker Desktop, so that they are available to your Linux containers.

Permission for shared drives are tied to the credentials you provide here. If you run dockercommands under a different username than the one configured here, your containers cannot access the mounted volumes.

To apply shared drives, you are prompted for your Windows system (domain) username and password. You can select an option to have Docker store the credentials so that you don’t need to enter them every time.

Tips on shared drives, permissions, and volume mounts

Shared drives are only required for mounting volumes in Linux containers, not for Windows containers. For Linux containers, you need to share the drive where the Dockerfile and volume are located. If you get errors such as file not found or cannot start service you may need to enable shared drives. See Volume mounting requires shared drives for Linux containers.)

If possible, avoid volume mounts from the Windows host, and instead mount on the Linux VM, or use a data volume (named volume) or data container. There are a number of issues with using host-mounted volumes and network paths for database files. See Volume mounts from host paths use a nobrl option to override database locking.

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.

Ensure the domain user has access to shared drives, as described in Verify domain user has permissions for shared drives.

You can share local drives with your containers but not with Docker Machine nodes. See the FAQ, Can I share local drives and filesystem with my Docker Machine VMs?.

FIREWALL RULES FOR SHARED DRIVES

Shared drives require port 445 to be open between the host machine and the virtual machine that runs Linux containers. Docker detects if port 445 is closed and shows the following message when you try to add a shared drive:

To share the drive, allow connections between the Windows host machine and the virtual machine in Windows Firewall or your third party firewall software. You do not need to open port 445 on any other network.

By default, allow connections to 10.0.75.1 on port 445 (the Windows host) from 10.0.75.2 (the virtual machine). If your firewall rules seem correct, you may need to toggle or reinstall the File and Print sharing service on the Hyper-V virtual network card

SHARED DRIVES ON DEMAND

You can share a drive “on demand” the first time a particular mount is requested.

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

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

Advanced

The Linux VM restarts after changing the settings on the Advanced tab. This takes a few seconds.

CPUs - Change the number of processors assigned to the Linux VM.
Memory - Change the amount of memory the Docker Desktop Linux VM uses.
Swap - Configure the swap file size.

Network

You can configure Docker Desktop networking to work on a virtual private network (VPN).

Internal Virtual Switch - You can 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 Stable version. This would manifest as an error when trying to run docker commands that pull images from Docker Hub that are not already downloaded, such as a first time run of docker run hello-world. If you encounter this, reset the DNS server to use the Google DNS fixed address: 8.8.8.8. For more information, see Networking issues in Troubleshooting.

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

Proxies

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

When you start a container, your proxy settings propagate into the containers. For example:

> docker run alpine env

PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
HOSTNAME=b7edf988b2b5
TERM=xterm
HOME=/root
HTTP_PROXY=http://proxy.example.com:3128
http_proxy=http://proxy.example.com:3128
no_proxy=*.local, 169.254/16

In the output above, the HTTP_PROXY, http_proxy, and no_proxy environment variables are set. When your proxy configuration changes, Docker restarts automatically to pick up the new settings. If you have containers that you wish to keep running across restarts, you should consider using restart policies.

Daemon

You can configure the Docker daemon to hone how your containers run. Advanced mode lets you edit the JSON directly. Basic mode lets you configure the common daemon options with interactive settings.

EXPERIMENTAL FEATURES

Docker Desktop Edge releases have the experimental version of Docker Engine enabled by default, described in the Docker Experimental Features README on GitHub.

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

To enable experimental features in the Docker CLI, edit the config.json file and set experimental to enabled.

To enable experimental features from the Docker Desktop menu, click Settings (Preferences on macOS) > Daemon and then select the Experimental features check box.

On both Edge and Stable releases, you can toggle the Experimental features on and off. If you toggle it off, Docker Desktop uses the current generally available release of Docker Engine.

Run docker version to see if you are in Experimental mode. Experimental mode is listed under Server data. If Experimental is true, then Docker is running in experimental mode, as shown here:

> docker version

Client: Docker Engine - Community
 Version:           19.03.1
 API version:       1.40
 Go version:        go1.12.5
 Git commit:        74b1e89
 Built:             Thu Jul 25 21:17:08 2019
 OS/Arch:           windows/amd64
 Experimental:      true

Server: Docker Engine - Community
 Engine:
  Version:          19.03.1
  API version:      1.40 (minimum version 1.12)
  Go version:       go1.12.5
  Git commit:       74b1e89
  Built:            Thu Jul 25 21:17:52 2019
  OS/Arch:          linux/amd64
  Experimental:     true
 containerd:
  Version:          v1.2.6
  GitCommit:        894b81a4b802e4eb2a91d1ce216b8817763c29fb
 runc:
  Version:          1.0.0-rc8
  GitCommit:        425e105d5a03fabd737a126ad93d62a9eeede87f
 docker-init:
  Version:          0.18.0
  GitCommit:        fec3683

INSECURE REGISTRIES

You can set up your own registries on the Basic Daemon settings.

Normally, you store public or private images in Docker Hub and Docker Trusted Registry. Here, you can use Docker to set up your own insecure registry. Simply add URLs for insecure registries and registry mirrors on which to host your images.

For more information, see How do I add custom CA certificates? and How do I add client certificates? in the FAQs.

DAEMON CONFIGURATION FILE

The Advanced daemon settings provide the original option to directly edit the JSON configuration file for the daemon.

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

For a full list of options on the Docker daemon, see daemon, and also sub-topics:

Kubernetes

Docker Desktop includes a standalone Kubernetes server that runs on your Windows host, so that you can test deploying your Docker workloads on Kubernetes.

The Kubernetes client command, kubectl, is included and configured to connect to the local Kubernetes server. If you have kubectl already installed and pointing to some other environment, such as minikube or a GKE cluster, be sure to change context so that kubectl is pointing to docker-for-desktop:

> kubectl config get-contexts
> kubectl config use-context docker-for-desktop

You can also change it through the Docker Desktop menu:

If you installed kubectl by another method, and experience conflicts, remove it.

To enable Kubernetes support and install a standalone instance of Kubernetes running as a Docker container, select Enable Kubernetes and click the Apply button. This instantiates images required to run the Kubernetes server as containers, and installs the kubectl.exe command in the path.
By default, Kubernetes containers are hidden from commands like docker service ls, because managing them manually is not supported. To make them visible, select Show system containers (advanced) and click Apply. Most users do not need this option.
To disable Kubernetes support at any time, deselect Enable Kubernetes. The Kubernetes containers are stopped and removed, and the /usr/local/bin/kubectl command is removed.

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

Reset

Reset and Restart options

On Edge releases, the Restart Docker Desktop, Reset Kubernetes Cluster, and Reset to factory defaults options are available on the Troubleshoot menu.

On Stable releases, you can restart Docker or reset its configuration using the Reset tab.

Restart Docker Desktop - Shuts down and restarts the Docker application.
Reset Kubernetes Cluster - Deletes all stacks and Kubernetes resources.
Reset to factory defaults - Resets Docker to factory defaults. This is useful in cases where Docker stops working or becomes unresponsive.

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 Windows containers, or select Switch to Linux containersto 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 MusicStore application 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, see Limitations 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:

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

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.

Answer Guruji(8920128728)

Saturday, August 31, 2019

Get started with Docker for Windows