Use k8saas from BYOD

Introduction

By default, k8saas is accessible from anywhere, from any device. Of course, based on the security level of each project k8saas is also compatible with other type of access to limit the exposure of application, to limit the laptop access etc...

The purpose of this documentation is to show you with a concrete use case, how to consume the k8saas service.

Tutorial

In this tutorial, you're going to:

get your k8saas credentials
deploy a hello world application
access to your application using a port-forward
expose your hello world to internet using the All in one application publication service
test the access from internet

Get your k8saas credentials

Prerequisites:

azure-cli
kubectl
kubelogin (from azure)

Install the following packages

brew update && brew install azure-cli && brew install kubectl && brew install Azure/kubelogin/kubelogin

You are going to receive by email:

K8SAAS_TENANT_ID: the tenant it
K8SAAS_SUBSCRIPTION_ID: the id of the subscription where your resources are deployed
K8SAAS_INSTANCE_NAME: the name of the kubernetes and the resource group

To first get the kubeconfig, run the following command:

# load environment variables
export K8SAAS_TENANT_ID="<K8SAAS_TENANT_ID>"
export K8SAAS_SUBSCRIPTION_ID="<K8SAAS_SUBSCRIPTION_ID>"
export K8SAAS_INSTANCE_NAME="<K8SAAS_INSTANCE_NAME>"

# be authenticated to azure
az login -t $K8SAAS_TENANT_ID
# get k8saas kubeconfig
az aks get-credentials --name $K8SAAS_INSTANCE_NAME --resource-group $K8SAAS_INSTANCE_NAME --subscription $K8SAAS_SUBSCRIPTION_ID
# skip MFA using azure credentials
kubelogin convert-kubeconfig -l azurecli

Once done, you should be able to access to your cluster. Note: by default there is a "customer-namespaces" namespace.

kubectl get pods --namespace customer-namespaces
kubectl get events --namespace customer-namespaces

Note:

list all namespace is currently forbidden

Deploy a hello world application

Here is a project to start deploying your first application.

Clone the project :

git clone https://gitlab.thalesdigital.io/platform-team-canada/k8saas-innersource/hello-world-k8saas.git
cd hello-world-k8saas/Basic-helloworld

Look at the first file: aks-helloworld-one.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: aks-helloworld-one
spec:
  replicas: 1
  selector:
    matchLabels:
      app: aks-helloworld-one
  template:
    metadata:
      labels:
        app: aks-helloworld-one
    spec:
      containers:
      - name: aks-helloworld-one
        image: mcr.microsoft.com/azuredocs/aks-helloworld:v1
        ports:
        - containerPort: 80
        env:
        - name: TITLE
          value: "Welcome to Azure Kubernetes Service (AKS)"
---
apiVersion: v1
kind: Service
metadata:
  name: aks-helloworld-one
spec:
  type: ClusterIP
  ports:
  - port: 80
  selector:
    app: aks-helloworld-one

This file is composed of:

a kubernetes deployment which contains a pod: aks-helloworld-one based on a microsoft image: mcr.microsoft.com/azuredocs/aks-helloworld:v1
a kubernetes service that exposes the previous container internally

Then deploy your applications :

# this start a hello world pod
kubectl apply -f aks-helloworld-one.yaml --namespace customer-namespaces

# look at your pods
kubectl get pods -n customer-namespaces
NAME                                  READY   STATUS    RESTARTS   AGE
aks-helloworld-one-56c7b8d79d-sm4c6   2/2     Running   0          10m

Access to your application using a port-forward

By default a pod is not accessible from outside the cluster. For development & testing purpose, it's possible to perfom a port-forward using native kubernetes commands.

# use the name of the pod in the following command:
kubectl port-forward pods/aks-helloworld-one-56c7b8d79d-sm4c6 -n customer-namespaces 8080:80

Forwarding from 127.0.0.1:8080 -> 80
Forwarding from [::1]:8080 -> 80
Handling connection for 8080

# Now access to your application locally
curl localhost:8080
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <link rel="stylesheet" type="text/css" href="/static/default.css">
    <title>Welcome to Azure Kubernetes Service (AKS)</title>

    <script language="JavaScript">
        function send(form){
        }
    </script>

</head>
<body>
    <div id="container">
        <form id="form" name="form" action="/"" method="post"><center>
        <div id="logo">Welcome to Azure Kubernetes Service (AKS)</div>
        <div id="space"></div>
        <img src="/static/acs.png" als="acs logo">
        <div id="form">
        </div>
    </div>
</body>
</html>%

Note: You can also perform a port-forward using the service:

kubectl get services -n customer-namespaces
NAME                 TYPE        CLUSTER-IP    EXTERNAL-IP   PORT(S)   AGE
aks-helloworld-one   ClusterIP   10.0.98.198   <none>        80/TCP    12m

kubectl port-forward services/aks-helloworld-one -n customer-namespaces 8080:80
Forwarding from 127.0.0.1:8080 -> 80
Forwarding from [::1]:8080 -> 80

You just succeed to access to your application without having exposed your application on internet. Now, we're going to expose your application using an ingress. It's like a proxy.

Expose your hello world to internet using the All in one application publication service

Then, look at the second file: hello-world-ingress.yaml

Update the following line:

line 11 & 14: update the url to use this pattern hello-world-ingress.<what_you_want>.kaas.thalesdigital.io

Note: avoid demo, test etc... for <what_you_want>. Otherwise, you risk having a conflict with the DNS.

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: hello-world-ingress
  annotations:
    cert-manager.io/cluster-issuer: letsencrypt-staging
spec:
  ingressClassName: nginx-internal
  tls:
  - hosts:
    - hello-world-ingress.jkfhsfkshdflkshjkdhf.kaas.thalesdigital.io
    secretName: tls-secret
  rules:
  - host: hello-world-ingress.jkfhsfkshdflkshjkdhf.kaas.thalesdigital.io
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: aks-helloworld-one
            port:
              number: 80

Once the file modify:

kubectl apply -f hello-world-ingress.yaml -n customer-namespaces
ingress.networking.k8s.io/hello-world-ingress created

# all look at the ingress
kubectl get ingress -n customer-namespaces -w
Warning: extensions/v1beta1 Ingress is deprecated in v1.14+, unavailable in v1.22+; use networking.k8s.io/v1 Ingress
NAME                  CLASS    HOSTS                                                        ADDRESS   PORTS     AGE
hello-world-ingress   <none>   hello-world-ingress.jkfhsfkshdflkshjkdhf.kaas.thalesdigital.io             80, 443   12s
hello-world-ingress   <none>   hello-world-ingress.jkfhsfkshdflkshjkdhf.kaas.thalesdigital.io   20.36.107.4   80, 443   12s

TADA ! Your application is exposed on HTTPS using a generated certificate (not valid because using letencrypt-staging. Use letencrypt-prod to get a valid certificate)

Let test few command:

nslookup hello-world-ingress.jkfhsfkshdflkshjkdhf.kaas.thalesdigital.io
Server:  192.168.2.1
Address: 192.168.2.1#53

Non-authoritative answer:
Name: hello-world-ingress.jkfhsfkshdflkshjkdhf.kaas.thalesdigital.io
Address: 20.36.107.4

The domain and the ip are both public.

Test the access from internet

Now you should access to your application from any where.

From a terminal:

curl -k https://hello-world-ingress.jkfhsfkshdflkshjkdhf.kaas.thalesdigital.io
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <link rel="stylesheet" type="text/css" href="/static/default.css">
    <title>Welcome to Azure Kubernetes Service (AKS)</title>

    <script language="JavaScript">
        function send(form){
        }
    </script>

</head>
<body>
    <div id="container">
        <form id="form" name="form" action="/"" method="post"><center>
        <div id="logo">Welcome to Azure Kubernetes Service (AKS)</div>
        <div id="space"></div>
        <img src="/static/acs.png" als="acs logo">
        <div id="form">
        </div>
    </div>
</body>
</html>%

From a browser:

Put the url of your application in your favorite browser: https://hello-world-ingress.<what_you_want>.kaas.thalesdigital.io

Next Steps

Secure your application using azure bastion
Deploy an application using an azure managed database

Introduction​

Tutorial​

Get your k8saas credentials​

Deploy a hello world application​