Istio Three (3) Cluster Multicloud Demo
This is a demonstration of the Hipster Shop running across three Kubernetes environments (Azure, GKE, and On-premises) using Istio. The demonstration was originally given to the audience at KubeCon EU 2019:
For those that want to skip ahead, the demo is here.
The objective of this repository is to teach new contributors how multicloud
works with Istio. As such, nothing all that advanced
is used beyond bash, helm, and kubectl commands. Once you are up
to speed, come join us
develop #multicloud in the Istio project.
Architecture
The Hipster Shop includes 10 microservices. Full details of the architecture and implementation of the Hipster Shop are available in that project. This architecture diagram shows how the Hipster shop is split across 3 clouds.
Files in this repository
| Component | Description |
|---|---|
license_header.txt |
A license header placed at the front of every K8s manifest |
make-manifests.sh |
Creates K8s manifests from a git clone of ../microservices-demo |
manifests |
Manifests generated from the make-manifests.sh script |
onprem |
Scripts to install docker, kubeadm/kubelet, and deploy Kubernetes |
Deploying the three (3) Kubernetes environments:
These steps are incomplete. This text will be removed when the steps are accurate and confirmed.
Prequisities
- There must be at minimum one Kubernetes control plane node and 1 Kubernetes
worker node. Most kubernetes cloud controllers suffer from
an issue
that does not permit the scheduling of services of type load balancer to an
all-in-onedeployment. - For On-Premises clusters using
metallb,
all-in-onedeployments Of Kubernetes and Istio work well. - Three clusters are needed. This demo uses Azure AKS, Google Cloud's GKE, and Kubernetes deployed on-premesis. The demo works equally well in one cloud provider or many. To demonstrate the full power of Istio the most challenging deployment scenario was chosen.
- Each cluster must implement a proper load balancer. Network load balancers
are the optimal choice, although others can be made to work with some
specific hacks, err,
systems engineering. - One load balancer must be available in the quota of the cloud provider.
- Sufficient security group rules quota must be available for Istio and the demonstration app. I have found through experimentation this number is at most 200 rules per cluster. Amazon Web Services defaults to 60 security groups per VPC, so you will need to request a quota increase to run this demo against AWS.
- Each cluster must meet the minimum requirements below to launch the demo properly. The CPU/Memory requests have been set to their minimums for Istio in the Istio manifests.
| CPU | Memory |
|---|---|
| 10 vCPU | 16.0 GiB |
Deploy an AKS cluster
Please follow the 5 minute quickstart for Azure CLI or Azure Portal to deploy a properly sized K8s cluster.
Deploy a GKE cluster
Please follow the GKE How-To to deploy a properly sized K8s cluster.
Deploy an On-Premises cluster
Please install Kubernetes and kubeadm and deploy an all-in-one cluster with
metallb.
There are several helper scripts in the onprem directory to install Kubernetes
and depooy Kubernetes 1.14.2 with metallb. I recommend using these if you don't
already have Kubernetes up and running.
In any event, it is mandatory to intall a Load Balancer provider. Typically this is provided by an internal or external cloud provider, however, in the case of bare metal, metallb works well for this purpose.