[ADD] k8s cluster setup guide

docs/k8s_cluster.md

@@ -1,8 +1,42 @@
-{!README.md!}
-
-# Welcome to Odoo SaaS on K8s documentation!
+# Kubernetes Cluster Setup
 
 
 !!! note
 
-    This project is under active development.
+    Following guide will be based on DigitalOcean Managed Kubernetes (DOKS) 
+
+
+Create a cluster and add node(s) in the cluster on DO,
+
+![Setup and Download Config File](img/k0.png)
+
+
+1.Install Nginx ingress controller in the cluster, with app installer
+2.Then loadbalancer will be provisioned automatically
+
+![Nginx Ingress Controller](img/k1.png)
+
+
+After pointing the domain to LB’s DNS and installing nginx ingress controller
+
+edit the LoadBalancer service (ingress-nginx/ingress-nginx-controller) using any tool, i am using k9s
+
+Add this
+
+    kubernetes.digitalocean.com/load-balancer-id: {id_of_lb_here}
+    service.beta.kubernetes.io/do-loadbalancer-enable-proxy-protocol: 'true'
+    service.beta.kubernetes.io/do-loadbalancer-hostname: yourdomain.com 
+ 
+
+![Nginx Ingress Controller Service](img/k2.png)
+
+
+
+Install cert-manager and ssl issuer. as per following guides
+
+
+[https://github.com/cert-manager/cert-manager](https://github.com/cert-manager/cert-manager)
+
+[https://kenanbek.github.io/kubernetes-https-nginx-ingress-cert-manager-digitalocean](https://github.com/cert-manager/cert-manager)
+
+[https://cert-manager.io/docs/installation/](https://github.com/cert-manager/cert-manager)