Run Docker Containers on Azure App Services

5 min readMay 1, 2019

When I was a fresh graduate, I remember being asked about the difference between SQL and a DBMS. I had spent a lot of time working with the former but I had no clue about how to work with the latter.

The cloud offers simple means to host websites without the developer needing to know how to configure a server. Translated, more time writing code and less in configuring servers.

Azure offers three options for hosting a website:

Azure App Services (and Azure Functions)
Virtual Machines
Service Fabrics

They support:

Multiple languages and frameworks, such as ASP.NET, ASP.NET Core, Java, Ruby, Node.js, PHP, or Python
They support background services running PowerShell and other scripts
They come with DevOps optimizations such as continuous integration, continuous deployment (optionally using Azure DevOps, GitHub, BitBucket, Docker Hub, or Azure Container Registry), test and staging environments
Global scale up or out. Microsoft’s global data center infrastructure spans around the entire globe. The servers come with a service level agreement currently set to a minimum of 99.95% of the time (not available for free or Shared tiers)

Connections to SaaS platforms (such as SAP, Salesforce), internet services (such as Facebook) and on-premises data (with Hybrid Connections and Azure Virtual Networks)
ISO, SOC, and PCI compliant
Social Logins (i.e. Microsoft, Google, Facebook, Twitter)
Application Templates, available in the Azure Marketplace, such as WordPress, Joomla, and Drupal
Integration with Visual Studio
API and Mobile Features such as CORS support, offline data sync, push notifications
Serverless code with Azure Functions

In the following steps, I will try to deploy a sample .NET Core website on a Docker container running on an Azure App Service.

What will be done is:

Create a resource group
Create an Azure Container Registry
Create a sample .NET Core website
Create an Azure App Service running the container

Create a Resource Group

A resource group is a container that holds related resources on Azure. They improve control of related resources.

Resources share the same lifecycle of their group
Each resource only exist in one group
Resources can be added or removed to a resource group at any time
Resources can be moved from one resource group to another
Resource groups can contain resources that reside in different regions
Resources can interact with resources in other resource groups

Your resource group will be available under the resource groups section:

Create an Azure Registry Container

A registry container will store your docker images, published using the Docker CLI.

Enable an admin used and take note of username and password. The will be needed to log in from the docker CLI.

Install Docker On your local machine

You will need to download Docker Desktop in order to user the Docker CLI.

This will require you to log out from your session:

After restarting, you will be prompted to enable Hiper-V and containerization for your Windows machine. Once that is done, you will be able to login in your Docker Desktop.

In order to test your installation, open a command prompt as Administrator and run

docker run -it hello-world

docker login deployanappservice.azurecr.io

Create a sample .NET Core web application

Always within the wizard, enable docker support:

On start, Visual Studio will automatically run scripts that will verify that your Desktop is running Docker and it will try to pull an image that will be used to deploy your website. The default image used by visual studio 2019 (Version 16.0.2) is the “aspenet:2.1-stretch-slim”.

The new project will come already with a working Dockerfile that should be fine.

Deploy your image on the Azure Container Registry

From the “Web Publish Activity” windows you will be able to monitor the publish progress. It will take some time for Docker to download all the required images.