Tutorial: Create an Azure container registry and push a container image

This article is part two of a three-part tutorial. Part one of the tutorial created a Docker container image for a Node.js web application. In this tutorial, you push the image to Azure Container Registry. If you need to create the container image, return to Tutorial 1 - Create container image.

Azure Container Registry is your private Docker registry in Azure. In this tutorial, part two of the series, you:

In the next article, the last in the series, you deploy the container from your private registry to Azure Container Instances.

Before you begin

You must satisfy the following requirements to complete this tutorial:

Azure CLI: You must have Azure CLI version 2.0.29 or later installed on your local computer. To find the version, run az --version. If you need to install or upgrade, see Install the Azure CLI.

Docker: This tutorial assumes a basic understanding of core Docker concepts like containers, container images, and basic docker commands. For a primer on Docker and container basics, see the Docker overview.

Docker: To complete this tutorial, you need Docker installed locally. Docker provides packages that configure the Docker environment on macOS, Windows, and Linux.

Create Azure container registry

Before you create your container registry, you need a resource group to deploy it to. A resource group is a logical collection into which all Azure resources are deployed and managed.

Create a resource group with the az group create command. In the following example, a resource group named myResourceGroup is created in the chinaeast2 region:

az group create --name myResourceGroup --location chinaeast2

Once you create the resource group, create an Azure container registry with the az acr create command. The container registry name must be unique within Azure, and contain 5-50 alphanumeric characters. Replace <acrName> with a unique name for your registry:

az acr create --resource-group myResourceGroup --name <acrName> --sku Basic

Here's partial output for a new Azure container registry named mycontainerregistry082:

{
  "creationDate": "2020-07-16T21:54:47.297875+00:00",
  "id": "/subscriptions/<Subscription ID>/resourceGroups/myResourceGroup/providers/Microsoft.ContainerRegistry/registries/mycontainerregistry082",
  "location": "chinaeast2",
  "loginServer": "mycontainerregistry082.azurecr.cn",
  "name": "mycontainerregistry082",
  "provisioningState": "Succeeded",
  "resourceGroup": "myResourceGroup",
  "sku": {
    "name": "Basic",
    "tier": "Basic"
  },
  "status": null,
  "storageAccount": null,
  "tags": {},
  "type": "Microsoft.ContainerRegistry/registries"
}

The rest of the tutorial refers to <acrName> as a placeholder for the container registry name that you chose in this step.

Sign in to container registry

You must sign in to your Azure Container Registry instance before pushing images to it. Use the az acr login command to complete the operation. You must provide the unique name you chose for the container registry when you created it.

az acr login --name <acrName>

For example:

az acr login --name mycontainerregistry082

The command returns Login Succeeded once completed:

Login Succeeded

Tag container image

To push a container image to a private registry like Azure Container Registry, you must first tag the image with the full name of the registry's login server.

First, get the full login server name for your Azure container registry. Run the following az acr show command, and replace <acrName> with the name of registry you created:

az acr show --name <acrName> --query loginServer --output table

For example, if your registry is named mycontainerregistry082:

az acr show --name mycontainerregistry082 --query loginServer --output table

Result
------------------------
mycontainerregistry082.azurecr.cn

Now, display the list of your local images with the docker images command:

docker images

Along with any other images you have on your machine, you should see the aci-tutorial-app image you built in the previous tutorial:

docker images

REPOSITORY          TAG       IMAGE ID        CREATED           SIZE
aci-tutorial-app    latest    5c745774dfa9    39 minutes ago    68.1 MB

Tag the aci-tutorial-app image with the login server of your container registry. Also, add the :v1 tag to the end of the image name to indicate the image version number. Replace <acrLoginServer> with the result of the az acr show command you executed earlier.

docker tag aci-tutorial-app <acrLoginServer>/aci-tutorial-app:v1

Run docker images again to verify the tagging operation:

docker images

REPOSITORY                                            TAG       IMAGE ID        CREATED           SIZE
aci-tutorial-app                                      latest    5c745774dfa9    39 minutes ago    68.1 MB
mycontainerregistry082.azurecr.cn/aci-tutorial-app    v1        5c745774dfa9    7 minutes ago     68.1 MB

Push image to Azure Container Registry

Now that you tagged the aci-tutorial-app image with the full login server name of your private registry, you can push the image to the registry with the docker push command. Replace <acrLoginServer> with the full login server name you obtained in the earlier step.

docker push <acrLoginServer>/aci-tutorial-app:v1

The push operation should take a few seconds to a few minutes depending on your internet connection, and output is similar to the following example:

docker push mycontainerregistry082.azurecr.cn/aci-tutorial-app:v1

The push refers to a repository [mycontainerregistry082.azurecr.cn/aci-tutorial-app]
3db9cac20d49: Pushed
13f653351004: Pushed
4cd158165f4d: Pushed
d8fbd47558a8: Pushed
44ab46125c35: Pushed
5bef08742407: Pushed
v1: digest: sha256:ed67fff971da47175856505585dcd92d1270c3b37543e8afd46014d328f05715 size: 1576

List images in Azure Container Registry

To verify that the image you just pushed is indeed in your Azure container registry, list the images in your registry with the az acr repository list command. Replace <acrName> with the name of your container registry.

az acr repository list --name <acrName> --output table

For example:

az acr repository list --name mycontainerregistry082 --output table

Result
----------------
aci-tutorial-app

To see the tags for a specific image, use the az acr repository show-tags command.

az acr repository show-tags --name <acrName> --repository aci-tutorial-app --output table

You should see output similar to the following example:

--------
v1

Next steps

In this tutorial, you prepared an Azure container registry for use with Azure Container Instances, and pushed a container image to the registry. The following steps were completed:

Advance to the next tutorial to learn how to deploy the container to Azure using Azure Container Instances: