Setting up a reverse proxy in AKS

January 27, 2023

Azure Kubernetes Service (AKS) is a managed Kubernetes service that makes it easy to deploy and manage containerized applications on Azure. One important aspect of managing containerized applications is routing incoming traffic to the appropriate service. In this blog post, we will look at how to set up a reverse proxy in AKS to route incoming traffic to the appropriate service.

What is a Reverse Proxy?

A reverse proxy is a server that sits in front of one or more web servers and acts as a gateway for incoming traffic. A reverse proxy can be used to handle tasks such as load balancing, SSL termination, and authentication. In the context of AKS, a reverse proxy can be used to route incoming traffic to the appropriate service based on the URL path or hostname.

Setting up a Reverse Proxy in AKS

To set up a reverse proxy in AKS, we will use the open-source reverse proxy software nginx. We will deploy nginx as a pod in our AKS cluster and configure it to route incoming traffic to the appropriate service.

Step 1: Deploy nginx as a pod

To deploy nginx as a pod in AKS, we will use the Kubernetes manifest file. The manifest file contains the configuration for the pod, including the container image, environment variables, and volumes.

Here is an example of a Kubernetes manifest file for deploying nginx as a pod in AKS:

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apiVersion: v1
kind: Pod
metadata:
  name: nginx-reverse-proxy
  labels:
    app: nginx-reverse-proxy
spec:
  containers:
  - name: nginx
    image: nginx:latest
    ports:
    - containerPort: 80

To deploy the pod, you can use the kubectl command-line tool, with the following command:

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kubectl apply -f nginx-pod.yaml

Step 2: Configure nginx to route traffic

Once the nginx pod is deployed, we need to configure it to route incoming traffic to the appropriate service. To do this, we will create a Kubernetes ConfigMap that contains the nginx configuration file.

Here is an example of a ConfigMap for routing incoming traffic to a service named web-service:

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apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-config
data:
  nginx.conf: |
    events {
    }
    http {
        server {
            listen 80;
            location / {
                proxy_pass http://web-service:80;
            }
        }
    }

To create the ConfigMap, you can use the kubectl command-line tool, with the following command:

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kubectl create configmap nginx-config --from-file=nginx.conf

Step 3: Create the services

After creating the ConfigMap, we need to create the services that the nginx reverse proxy will route the traffic to.

Here is an example of a Kubernetes service for the web-service:

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apiVersion: v1
kind: Service
metadata:
  name: web-service
  labels:
    app: web-service
spec:
  ports:
  - port: 80
    targetPort: 80
  selector: