docs/install

Knative the easy way

This guide walks you through the installation of the latest version of Knative using pre-built images and demonstrates deployment of a sample app onto the newly created Knative cluster.

Prerequisites

Knative requires a Kubernetes cluster (v1.10 or newer). If you don't have one, you can create one on Google Cloud Platform. You can also use Minikube; see the Knative the easy way with Minikube guide for instructions.

First, define a few environment variables. If you already have a default project set in gcloud, enter:

export PROJECT_ID=$(gcloud config get-value project)

Or, if you don't have an existing GCP project you'd like to use, replace my-knative-project with your desired project ID. This variable will be used later to create your new GCP project. The project ID must be globally unique across all GCP projects.

export PROJECT_ID=my-knative-project

Set the following two variables as desired:

export CLUSTER_NAME=knative
export CLUSTER_ZONE=us-west1-c

Setup

gcloud CLI

If you already have gcloud installed, you can skip this section.

Download and install the gcloud command line tool:

https://cloud.google.com/sdk/

Authorize gcloud:

gcloud auth login

Google Cloud Platform Project

If you already have a GCP project configured, make sure your project is set as your gcloud default:

gcloud config set project $PROJECT_ID

If you don't already have a GCP project configured, create a new project:

gcloud projects create $PROJECT_ID --set-as-default

Enable the necessary APIs:

gcloud services enable \
  cloudapis.googleapis.com \
  container.googleapis.com \
  containerregistry.googleapis.com

Kubernetes

Create a Kubernetes cluster on GKE (large enough to host all the Knative and Istio components):

gcloud container clusters create $CLUSTER_NAME \
  --zone=$CLUSTER_ZONE \
  --cluster-version 1.10.4-gke.2 \
  --machine-type n1-standard-4 \
  --enable-autoscaling --min-nodes=1 --max-nodes=10 \
  --scopes=cloud-platform,logging-write,monitoring-write,pubsub \
  --num-nodes 3 \
  --image-type ubuntu

Grant cluster-admin permissions to the current user:

kubectl create clusterrolebinding cluster-admin-binding \
  --clusterrole=cluster-admin \
  --user=$(gcloud config get-value core/account)

Admin permissions are required to create the necessary RBAC rules for Istio.

Istio

Knative depends on Istio. Install Istio:

kubectl apply -f https://storage.googleapis.com/knative-releases/latest/istio.yaml

# Label the default namespace with istio-injection=enabled.
kubectl label namespace default istio-injection=enabled

Wait until each Istio component is ready (STATUS column shows 'Running' or 'Completed'):

kubectl get pods -n istio-system --watch

CTRL+C when it's done.

Knative

Next, we will install Knative:

kubectl apply -f https://storage.googleapis.com/knative-releases/latest/release.yaml

Wait until each Knative component is running (STATUS column shows 'Running'):

kubectl get pods -n knative-serving --watch

CTRL+C when it's done.

Now you can deploy your app or function to your newly created Knative cluster.

Test App

The following instructions will deploy the Primer sample app onto your new Knative cluster.

Note, you will be deploying using a pre-built image so no need to clone the Primer repo or install anything locally. If you want to run the Primer app locally, see the Primer Readme for instructions.

kubectl apply -f https://storage.googleapis.com/knative-samples/primer.yaml

Wait for the ingress to obtain a public IP. This may take a few seconds. You can check by running:

kubectl get ing --watch

CTRL+C when it's done.

Capture the IP and host name in environment variables by running these commands:

export SERVICE_IP=$(kubectl get ing primer-ingress \
  -o jsonpath="{.status.loadBalancer.ingress[0]['ip']}")
  
export SERVICE_HOST=$(kubectl get ing primer-ingress \
  -o jsonpath="{.spec.rules[0]['host']}")

Alternatively, you can create an entry in your DNS server to point your subdomain to the IP.

Run the Primer app:

curl -H "Host: ${SERVICE_HOST}" http://$SERVICE_IP/5000000

The higher the number, the longer it will run.

Cleanup

Delete the Kubernetes cluster, which deletes Knative, Istio, and the Primer sample app:

gcloud container clusters delete $CLUSTER_NAME --zone $CLUSTER_ZONE