Azure Kubernetes Service (AKS) Learning Series

Demo code for Hands on Series for Azure kubernetes Series (AKS) learning series. The series is delivered as part of Azure Learning Series for the Microsoft Azure user group in Singapore. The objective of this series is to learn about containerizing multi-container application using Docker. The multi-container application is then deployed to a managed Kubernetes cluster using Azure Kubernetes Service.

Application Overview

The application makes use of ASP.Net Core for building a MVC front end. It is an application for managing hypothetical events for TechTalks. The front end interacts with an backend ASP.Net Core API. SQL Server 2017 provides the persistent storage. All these 3 components are containerized using Docker.

The application is deployed to Azure Kubernetes Service (AKS) cluster in a multinode environment.

We used Azure Disk to manage database state using Persistent Volume and Persistent Volume Claim. Finally we used Azure Monitoring to monitor the cluster state and also an open source solution with Prometheus and Grafana as an alternative to Azure Monitor.

Here is an example of Grafana dashboard for Kubernetes Capacity Planning

Grafana dashboard for pod utilization

Code organization

Docker-compose V1

Contains the docker-compose file in its simplest form

Docker-compose V2

Contains the docker-compose files split into a base compose file and separate files for build and run scenarios. This is a preferred approach as it allows to have clear separation in terms of images which are built as part of application code and images which are used from other pre-built images. This also allows us to separate configurations between different environments like Dev / Integration / Production etc.

Helm

Contains the Helm charts which are useful for deploying Kubernetes applications. Refer to the Helm readme file for more details.

k8s

Contains Kubernetes Manifest files. These are grouped into Minikube version with services exposed using NodePort type. AKS version exposes the TechTalksWeb and TechTalksDB using LoadBalancer. The data is also persisted to outside of the container using Persistent Volume (PV) and Persistent Volume Claim (PVC). The volume is backed by Azure Disk.

AKS version contians the Kubernetes Manifest files for deploying Prometheus and Grafana resources to the AKS cluster. These are used for monitoring the AKS cluster.

Powershell

Contains the powershell scripts used for deploying application resources to Minikube or AKS cluster

Skaffold

Skaffold adds ability to do continuous deployment of Kubernetes application. This is similar to live unit testing feature. Refer to the two links below to know more about using Skaffold.

1 - Use Skaffold with Minikube

2 - Use Skaffold with Docker for Mac with Kubernetes

src

Contains the source code.

- `TechTalksAPI` contains code for Web API project

- `TechTalksDB` contains database initialization script

- `TechTalksWeb` contains code for ASP.Net Core MVC frontend

Minikube

Contains instructions for setting up Minikube cluster and Kubectl

Setup Development environment

The project is based on .Net Core 2.1 framework. The application is built using Docker Multi-Stage builds and does not require the base machine to have .Net Core or runtime to be installed. It is recommended to install .Net Core framework locally on the machine if you wish to debug the code.