Open source project - Demo - Azure Kubernetes Service(AKS) & Ingress

Deploying applications in MS Azure AKS using Ingress (NGINX Ingress Controller)

• Microsoft Azure Kubernetes Service (AKS) is a fully managed container orchestration service. It reduces the complexity of container deployment and management and provides automation.
  
• Azure automatically creates and configures a Kubernetes control plane for each cluster. In addition, MS handles all Kubernetes upgrades and new version updates within AKS.
  
• Using AKS doesn’t attract cluster management and master node fees, unlike other platforms. Customer is charged for the network resources, worker nodes & other Azure resouces that are used.
  
• Infrastructure management is smooth; AKS elastically provisions resources, so customers/developers don’t need to worry about whether they’re being used effectively.
  
• Azure AKS Architecture :
  A Kubernetes cluster is divided into two components:
  
  • Control plane: provides the core Kubernetes services and orchestration of application workloads. This is managed by Azure
    
  • Nodes: run client application workloads on Kubernetes.
    
    
• Ingress is a Kubernetes API object that maps an application to a stable, externally addressable HTTP or HTTPS URL. It can route traffic to multiple services
  
  
• Ingress controllers work at layer 7 and can use more intelligent rules to distribute application traffic. Ingress controllers typically route HTTP/HTTPS traffic to different applications based on the inbound URL.
  
  

Steps to be followed :

• Clone the repository and navigate to the folder lab-05
  

• Open powershell in administrator mode and login with below command. If you have multiple subscriptions then select the correct subcription by second command
  $ az login --use-device
  $ az account set --subscription <<-subsctption name/id->> (optional if you have multiple subcriptions)
  

• To view the current/default subscrition use the below command (optional).
  $ az account show --output table
  

• Create resource group "aksdemo".
  $ az group create --name aksdemo --location southeastasia
  

• Create an AKS cluster with 2 nodes (if you want to attach ACR then add --attach-acr )
  $ az aks create --name aksdemo -g aksdemo --node-count 2 --generate-ssh-keys
  

• Switch context. (To configure kubectl to connect to your Kubernetes cluster, use the az aks get-credentials command).
  $ az aks get-credentials -n aksdemo -g aksdemo
  

• Refer below commands for verification of contexts.
  $ kubectl config view
  $ kubectl config current-context (output should be aksdemo).
  $ kubectl config get contexts
  $ kubectl config use-context <<-context name->>
  

• Check nodes and pods in your AKS cluster.
  $ kubectl get nodes -o wide
  $ kubectl get pods
  

• Add a NGINX ingress controller without customizing the defaults. The last command is deprecated & if 3rd command works then no need to execute last command
  $ helm repo add ingress-nginx https://kubernetes.github.io/ingress-nginx
  $ helm repo update
  $ helm install nginx-ingress ingress-nginx/ingress-nginx --create-namespace --namespace ingress-basic --set controller.replicaCount=2 --set controller.nodeSelector."kubernetes.io/os"=linux --set defaultBackend.nodeSelector."kubernetes.io/os"=linux
  $ helm install nginx-ingress ingress-nginx/ingress-nginx --create-namespace --namespace ingress-basic --set controller.replicaCount=2 --set controller.nodeSelector."beta.kubernetes.io/os"=linux --set defaultBackend.nodeSelector."beta.kubernetes.io/os"=linux
  

• Verify NGINX controller installation
  $ kubectl get pods -n ingress-basic -l app.kubernetes.io/name=ingress-nginx --watch
  

• Inspect the ingress controller Service
  $ kubectl get svc -n ingress-basic
  
  

  Deploy the application (s)

• Deploy the cats application (pod and ClusterIP service)
  $ kubectl apply -f cats.yaml
  

• Deploy the "Dogs" application (pod and ClusterIP service)
  $ kubectl apply -f dogs.yaml
  

• Deploy the "Birds" application (pod and ClusterIP service)
  $ kubectl apply -f birds.yaml
  

• Create the ingress resource
  $ kubectl apply -f ingress.yaml
  

• List existing pods & services
  $ kubectl get pods
  $ kubectl get svc
  

• List existing ingress
  $ kubectl get ingress
  
  

Access the application

• Get the ingress controller External IP (type LoadBalancer)
  $ kubectl get svc -n ingress-basic
  
• Browse to the cats, dogs and birds service
  $ http://<<-ingress-controller-external-ip->>/cats
  $ http://<<-ingress-controller-external-ip->>/dogs
  $ http://<<-ingress-controller-external-ip->>/birds
  
• Clean up resources
  $ kubectl get all
  $ kubectl delete all --all
  $ kubectl delete ingress --all
  $ kubectl delete all --all -n ingress-basic
  $ kubectl delete namespace ingress-basic
  
• List existing resources
  $ kubectl get all
  
• Clean your Azure enviornment. Other than "aksdemo" there will be an autogenerated resource group created which also needs to be deleted
  $ az group delete --name <<-resource group name->> --yes -y
  $ az group delete --name aksdemo --yes -y
  
  

Further References :

• Kubernetes core concepts for Azure Kubernetes Service (AKS)
  
• Optimize compute costs on Azure Kubernetes Service (AKS)
  
• Top 10 Cost Optimization Techniques for AKS Workloads running in Azure
  
• Azure Kubernetes Service (AKS)
  
• What is Application Gateway Ingress Controller?
  
• Is ingress-nginx really a load balancer or not?
  
• Network concepts for applications in Azure Kubernetes Service (AKS)