multi

Summary

In this lab, you will learn how to install and configure a multi-cluster mesh

Table of Contents

• How does it work?
• Setup and Requirements

How does it work

NOTE: I think this is an area of Istio that is rapidly changing (improving). The statements below are true for Istio 1.0.

Prerequisites

• Kubernetes v1.9 or higher; 1.10 is preferred.
• Helm 2.7.2 or higher
• Istio control plane installed on a Kubernetes cluster (which will be referred to as master)
• All pod CIDRs in every cluster must be routable to each other

Setup and Requirements

WORK IN PROGRESS

1. Complete Istio installation on the master cluster as described in the previous labs.

2. Configing the remote cluster

• Create a new GKE cluster

3. Install a sample application in the remote cluster

Create a file hello.yaml with the following contents

apiVersion: v1
kind: Service
metadata:
  name: helloworld
  labels:
    app: helloworld
spec:
  ports:
  - port: 5000
    name: http
  selector:
    app: helloworld
---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: helloworld-v1
spec:
  replicas: 1
  template:
    metadata:
      labels:
        app: helloworld
        version: v1
    spec:
      containers:
      - name: helloworld
        image: istio/examples-helloworld-v1
        resources:
          requests:
            cpu: "100m"
        imagePullPolicy: IfNotPresent #Always
        ports:
        - containerPort: 5000

kubectl apply -f <(istioctl kube-inject -f hello.yaml)>  

Testing the setup

Get the Cluster IP of the details application (from the master cluster)

kubectl get svc

OUTPUT:

NAME          TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)             AGE
details       ClusterIP   10.35.248.207   <none>        9080/TCP            18d

Access the bash shell in the helloworld application

kubectl exec -it helloworld-v1-c5c996c78-xw8d2 bash

Access the details IP with the cluster IP

curl 10.35.248.207:9080/details/0

OUTPUT:

{"id":0,"author":"William Shakespeare","year":1595,"type":"paperback","pages":200,"publisher":"PublisherA","language":"English","ISBN-10":"1234567890","ISBN-13":"123-1234567890"}

Observations

• At the moment, DNS is the responsibility of the user (Istio does not provide a solution)
• There are a few options discussed in the community here