Add AKS installation walkthrough (#210)

* Add install on AKS doc

This PR adds a walkthrough providing instructions on how to install knative
on Azure Kubernetes Service. It also adds a little more wording to the opening
of README.md.

Closes: #208

* Formatting cleanup

* Small cleanup

* Added missed CLI docs

* Cleanup aks get credentials text

* Wrap az aks line

install/Knative-with-AKS.md

@@ -0,0 +1,188 @@
+# Knative Install on Azure Kubernetes Service (AKS)
+
+This guide walks you through the installation of the latest version of
+Knative using pre-built images.
+
+You can find [guides for other platforms here](README.md).
+
+## Before you begin
+
+Knative requires a Kubernetes cluster v1.10 or newer. `kubectl` v1.10 is also
+required.  This guide walks you through creating a cluster with the correct
+specifications for Knative on Azure Kubernetes Service (AKS).
+
+This guide assumes you are using bash in a Mac or Linux environment; some
+commands will need to be adjusted for use in a Windows environment.
+
+### Installing the Azure CLI
+
+1. If you already have `azure cli` version `2.0.41` or later installed, you can skip to the next section and install `kubectl`
+
+Install `az` by following the instructions for your operating system.
+See the [full installation instructions](https://docs.microsoft.com/en-us/cli/azure/install-azure-cli?view=azure-cli-latest) if yours isn't listed below. You will need az cli version 2.0.37 or greater.
+
+#### MacOS
+
+```console
+brew install azure-cli
+```
+
+#### Ubuntu 64-bit
+
+1. Add the azure-cli repo to your sources:
+    ```console
+    echo "deb [arch=amd64] https://packages.microsoft.com/repos/azure-cli/ wheezy main" | \
+         sudo tee /etc/apt/sources.list.d/azure-cli.list
+    ```
+1. Run the following commands to install the Azure CLI and its dependencies:
+    ```console
+    sudo apt-key adv --keyserver packages.microsoft.com --recv-keys 52E16F86FEE04B979B07E28DB02C46DF417A0893    
+    sudo apt-get install apt-transport-https
+    sudo apt-get update && sudo apt-get install azure-cli
+    ```
+
+### Installing kubectl
+
+1. If you already have `kubectl`, run `kubectl version` to check your client version. If you have `kubectl` v1.10 installed, you can skip to the next section and create an AKS cluster
+
+```bash
+az aks install-cli
+```
+
+## Cluster Setup
+
+Now that we have all the tools, we need a Kubernetes cluster to install Knative.
+
+### Configure your Azure account
+
+First let's identify your Azure subscription and save it for use later.
+
+1. Run `az login` and follow the instructions in the command output to authorize `az` to use your account
+1. List your Azure subscriptions:
+    ```bash
+    az account list -o table
+    ```
+### Create a Resource Group for AKS
+
+ To simplify the command lines for this walkthrough, we need to define a few
+environment variables. First determine which region you'd like to run AKS in, along with the resource group you'd like to use.
+
+1. Set `RESOURCE_GROUP` and `LOCATION` variables:
+   ```bash
+   export LOCATION=east-us
+   export RESOURCE_GROUP=knative-group
+   export CLUSTER_NAME=knative-cluster
+   ```
+
+2. Create a resource group with the az cli using the following command if you are using a new resource group.
+   ```bash
+   az group create --name $RESOURCE_GROUP --location $LOCATION
+   ```
+
+### Create a Kubernetes cluster using AKS
+
+Next we will create a managed Kubernetes cluster using AKS. To make sure the cluster is large enough to host all the Knative and Istio components, the recommended configuration for a cluster is:
+
+* Kubernetes version 1.10 or later
+* Three or more nodes
+* Standard_DS3_v2 nodes
+* RBAC enabled
+
+1. Enable AKS in your subscription, use the following command with the az cli:
+    ```bash
+    az provider register -n Microsoft.ContainerService
+    ```
+You should also ensure that the `Microsoft.Compute` and `Microsoft.Network` providers are registered in your subscription. If you need to enable them:
+    ```bash
+    az provider register -n Microsoft.Compute
+    az provider register -n Microsoft.Network
+    ```
+1. Create the AKS cluster!
+    ```bash
+    az aks create --resource-group $RESOURCE_GROUP \
+    --name $CLUSTER_NAME \
+    --generate-ssh-keys \
+    --kubernetes-version 1.10.5 \
+    --enable-rbac \
+    --node-vm-size Standard_DS3_v2
+    ```
+
+1. Configure kubectl to use the new cluster.
+    ```bash
+    az aks get-credentials --resource-group $RESOURCE_GROUP --name $CLUSTER_NAME --admin
+    ```
+
+1. Verify your cluster is up and running
+    ```bash
+    kubectl get nodes
+    ```
+
+## Installing Istio
+
+Knative depends on Istio.
+
+1. Install Istio:
+    ```bash
+    kubectl apply -f https://storage.googleapis.com/knative-releases/latest/istio.yaml
+    ```
+1. Label the default namespace with `istio-injection=enabled`:
+    ```bash
+    kubectl label namespace default istio-injection=enabled
+    ```
+
+1. Monitor the Istio components until all of the components show a `STATUS` of
+`Running` or `Completed`:
+    ```bash
+    kubectl get pods -n istio-system
+    ```
+
+It will take a few minutes for all the components to be up and running; you can
+rerun the command to see the current status.
+
+> Note: Instead of rerunning the command, you can add `--watch` to the above
+  command to view the component's status updates in real time. Use CTRL + C to exit watch mode.
+
+## Installing Knative Serving
+
+1. Next, we will install [Knative Serving](https://github.com/knative/serving)
+and its dependencies:
+    ```bash
+    kubectl apply -f https://storage.googleapis.com/knative-releases/latest/release.yaml
+    ```
+1. Monitor the Knative components, until all of the components show a `STATUS` of
+`Running`:
+    ```bash
+    kubectl get pods -n knative-serving
+    ```
+
+Just as with the Istio components, it will take a few seconds for the Knative
+components to be up and running; you can rerun the command to see the current status.
+
+> Note: Instead of rerunning the command, you can add `--watch` to the above
+  command to view the component's status updates in real time. Use CTRL + C to exit watch mode.
+
+You are now ready to deploy an app to your new Knative cluster.
+
+## Deploying an app
+
+Now that your cluster has Knative installed, you're ready to deploy an app.
+
+You have two options for deploying your first app:
+
+* You can follow the step-by-step
+  [Getting Started with Knative App Deployment](getting-started-knative-app.md)
+  guide.
+
+* You can view the available [sample apps](../serving/samples/README.md) and
+  deploy one of your choosing.
+
+## Cleaning up
+
+Running a cluster costs money, so you might want to delete the cluster when you're done if 
+you're not using it. Deleting the cluster will also remove Knative, Istio, 
+and any apps you've deployed.
+
+To delete the cluster, enter the following command:
+```bash
+az aks delete --resource-group $RESOURCE_GROUP --name $CLUSTER_NAME --yes --no-wait
+```

install/README.md

@@ -9,7 +9,7 @@ sure which Kubernetes platform is right for you, see
 [Picking the Right Solution](https://kubernetes.io/docs/setup/pick-right-solution/).
 
 We provide information for installing Knative on
-[Google Kubernetes Engine](https://cloud.google.com/kubernetes-engine/docs/) and
+[Google Kubernetes Engine](https://cloud.google.com/kubernetes-engine/docs/), [IBM Cloud Kubernetes Service](https://www.ibm.com/cloud/container-service), [Azure Kubernetes Service](https://docs.microsoft.com/en-us/azure/aks/) and 
 [Minikube](https://kubernetes.io/docs/setup/minikube/) clusters.
 
 ## Installing Knative
@@ -20,6 +20,7 @@ Knative components on the following platforms:
 * [Knative Install on Gardener](Knative-with-Gardener.md)
 * [Knative Install on Google Kubernetes Engine](Knative-with-GKE.md)
 * [Knative Install on IBM Cloud Kubernetes Service](Knative-with-IKS.md)
+* [Knative Install on Azure Kubernetes Service](Knative-with-AKS.md)
 * [Knative Install on Minikube](Knative-with-Minikube.md)
 
 ## Deploying an app