Azure Container Apps Overview and Best Practices

Azure Container Apps is a fully managed platform that allows you to deploy and manage containerized applications in a scalable and secure way.

With Azure Container Apps, you can deploy applications in a matter of minutes, without the need for manual configuration or management of underlying infrastructure.

This platform supports a wide range of container runtimes, including Docker and Kubernetes, making it a versatile choice for developers.

It's also worth noting that Azure Container Apps is designed to work seamlessly with other Azure services, such as Azure Kubernetes Service (AKS) and Azure DevOps.

Azure Container Apps is composed of several key components that work together to provide a seamless and flexible serverless container hosting environment.

These components include Azure Container Apps itself, which is a managed platform for running and scaling containerized applications. It's designed to make it easy to deploy, manage, and scale containerized applications.

Azure Container Apps Components are the building blocks of this platform, and they work together to provide a robust and scalable environment for running containerized applications.

Azure Container Apps is composed of several key components that work together to provide a seamless and flexible serverless container hosting environment. These components make it possible to manage and deploy containers with ease.

Azure Container Apps supports both HTTP and HTTPS ingress, allowing you to control how external traffic reaches your Container Apps. You can configure custom domains, SSL/TLS certificates, authentication, and authorization through the ingress settings.

Networking rules can be defined to manage how your application communicates internally and with the outside world. This includes securing connections and integrating with private networks for enhanced security.

You can attach Azure Storage accounts as volumes in your container, allowing your application to access persistent storage. This is particularly useful for applications that require data to be stored and retrieved.

Azure Container Apps supports multiple container registries, including Azure Container Registry and Docker Hub. This flexibility makes it easy to manage and deploy containers from various sources.

Here are some of the key components that make up Azure Container Apps:

These components work together to provide a robust and scalable container hosting environment. By leveraging these components, you can build and deploy container-based applications with confidence.

In Azure Container Apps, there are two main types of containers: App Container and Init Containers.

The App Container, also known as a Sidecar, is the container that runs your application code.

Init Containers run before the App Container starts, making them essential for setting up the environment before your app is launched.

Secret Management is crucial for storing sensitive configuration elements securely.

You can store sensitive configuration elements in Azure Container Apps and make them available to containers through environment variables, scale rules, and Dapr.

Environment variables can also reference an Azure Key Vault for added security.

For more information on managing secrets in Azure Container Apps, check out the Microsoft documentation on managing secrets.

Networking & Storage is a crucial aspect of Azure Container Apps, allowing you to manage how your application communicates with the outside world.

A container app can take advantage of multiple types of storage if needed.

You can define user-defined routes in Azure Container Apps, which is essential for managing traffic to your application.

User-defined routes are a feature in Azure Container Apps Networking & Storage.

Azure Container Apps supports both HTTP and HTTPS ingress, giving you flexibility in how external traffic reaches your application.

You can configure custom domains, SSL/TLS certificates, authentication, and authorization through the ingress settings.

Networking rules can be defined to manage how your application communicates internally and with the outside world.

These rules help secure connections and integrate with private networks for enhanced security.

You can attach Azure Storage accounts as volumes in your container, allowing your application to access persistent storage.

Use storage mounts in Azure Container Apps to take advantage of different types of storage.

There are many other settings you can define for the Container App component, including assigning a managed identity for accessing other Azure services securely.

Azure Container Apps simplifies deployment and management of containerized applications. Container orchestration is essential for managing and scaling containerized applications.

Container orchestration tools like Kubernetes allow you to dynamically scale your application by adding or removing containers based on demand. Load balancing ensures that incoming requests are distributed evenly across containers, preventing overload on any single instance.

Common tools for deploying Azure Container Apps include Azure Portal Deployment, Azure CLI deployment, ARM template deployment, Bicep template deployment, Terraform template deployment, and Pulumi or other API tools.

The following table summarizes the deployment options for Azure Container Apps:

Deployment modes can be a bit tricky, but let's break it down.

In traditional monolith applications, spinning up new machines for each instance can be slower.

Microservices, on the other hand, instantiate services instead of spinning up new machines, which is faster.

Better hardware utilization is a key advantage of microservices, resulting in optimized cost due to efficient resource usage.

In contrast, monolith applications have less efficient utilization of hardware, potentially leading to higher costs.

A lower time to market is another benefit of microservices, as developers are more confident when upgrading a service.

Monolith applications, however, have a higher time to market due to the complexity of upgrading all components together.

Microservices are independently implemented, deployed, scaled, and versioned, making them more flexible.

Monolith applications, on the other hand, have all components tightly coupled and scaled together.

Here's a comparison of deployment modes:

Container orchestration is a crucial step in managing and scaling containerized applications. It allows you to dynamically scale your application by adding or removing containers based on demand.

Existing container orchestration solutions include Kubernetes, Docker Swarm, Amazon ECS, Azure Kubernetes Service (AKS), and Azure Container Apps. Each has its pros and cons, but they all provide essential features for managing containerized applications.

Container orchestration simplifies deployment, enhances reliability, and ensures efficient management of containerized applications. It provides features such as scaling and load balancing, high availability, service discovery and DNS, rolling updates and rollbacks, configuration management, resource optimization, networking and security, and monitoring and logging.

Here are some key features of container orchestration:

The Migration Plan was a crucial step in our journey to improve deployment and orchestration. We aimed to migrate existing Function Apps to run as standard ASP.NET Core .NET 6.0 apps.

Our plan involved three key steps: migrating Function Apps, updating back-end build and deployment pipelines, and redeploying container apps in our test environment. We also planned to leverage learnings from James Dawson's Adventures in Dapr.

We wanted to output, consume, and deploy container images instead of zipped-up code in our updated build and deployment pipelines. This required significant changes to our existing processes.

Here's a summary of our planned migration steps:

We were eager to put our new knowledge of Dapr to good use, but things didn't quite go as planned.

To deploy an application, you can use various tools, such as Azure Portal Deployment, Azure CLI deployment, ARM template deployment, Bicep template deployment, Terraform template deployment, or Pulumi or other API tools.

You can choose the deployment method that best suits your needs, depending on your familiarity with the tool and your specific requirements.

To deploy an application using Azure Container Apps, you'll need to create a Container Apps environment, which provides a managed platform for running and scaling containerized applications.

Here are the common tools used for deploying Container Apps:

Once you've created a Container Apps environment, you can deploy an application into it using one of these tools.

Observability and monitoring are crucial aspects of Azure Container Apps. With Azure Container Apps, you get a holistic view of your container app's health throughout its application lifecycle.

Azure Container Apps provides several built-in observability features that help in monitoring and diagnosing the state of the application. These features improve performance and respond to trends and critical problems.

During the development and test phase, you have real-time access to containers' application logs and console for debugging issues. This is made possible by log streaming and the container console.

You can monitor your application's performance and resource consumption continuously after deployment. Azure Monitor metrics, Azure Monitor alerts, and Azure Monitor Log Analytics help identify problems around error rates, performance, and resource consumption.

Azure Monitor metrics, Azure Monitor alerts, and Azure Monitor Log Analytics are also used during the maintenance phase to manage updates to your container app. This involves creating revisions and running multiple revisions concurrently for blue green deployments or A/B testing.

Here's an overview of the observability features available during different phases of the application lifecycle:

Azure Container Apps offers a unique pricing model with two modes: "Active" and "Inactive". The pricing for these modes differs significantly.

You're billed based on the vCPU cores and memory you specify when provisioning the container app. This means you need to carefully consider your resource allocation to avoid unnecessary costs.

Incoming requests are also billed at a ridiculously low rate of £0.33 per million requests. This is a small price to pay for the benefits of having a container app always available.

There's a monthly free grant, but it's not specified how much it is. This could be a significant advantage for small-scale applications.

To determine the cost of an idle container app, you need to calculate the idle usage price based on your resource allocation. For example, if you provision a container app with 0.5 vCPU cores and 1 GiB of memory, the idle usage price would be significantly lower than the active price.

Here's a rough estimate of the cost per month for a fully idle container app deployed into North Europe:

Keep in mind that these prices are estimates and may vary depending on your specific usage and location. It's essential to review the pricing documentation for the most up-to-date information.