TheLazy.Dev
Portfolio GitHub

Blog

cloud |kubernetes |istio |knative

Install Knative with Istio on IBM Cloud: the hard way

vidyasagarmsc

Vidyasagar SC Machupalli

Posted on March 14, 2019

Install Knative with Istio on IBM Cloud: the hard way

In this tutorial, learn how easy it is to install Knative with Istio on IBM Cloud Kubernetes Service(IKS), build and push an image to IBM Cloud Container Registry and deploy a nodejs app.

Before jumping into the instructions, let’s quickly understand what Knative is and what are its key components.

Knative extends Kubernetes to provide the missing building blocks that developers need to create modern, source-centric, container-based, cloud-native applications.

Each of the components under the Knative project attempt to identify common patterns and codify the best practices shared by successful real-world Kubernetes-based frameworks and applications, such as:

  • orchestrating source-to-container workflows
  • routing and managing traffic during deployment
  • scaling and sizing resources based on demand
  • binding running services to eventing ecosystems

Knative focuses on the “boring but difficult” parts that everyone needs, but no one benefits from doing over again on their own. This, in turn, frees developers to spend more time writing application code, not worrying about how they are going to build, deploy, monitor, and debug it.

What are the Knative components?

Currently, Knative consists of the following top-level repositories:

  • build and build-templates — automatic, repeatable server-side container builds
  • serving — scale to zero, request-driven compute
  • eventing — management and delivery of events

We expect this list to grow as more areas are identified.

Prerequisites

Setup CLI

If you already have ibmcloud CLI installed with the ibmcloud plugins, you can skip these steps.

  • Install the cs (container-service) and cr (container-registry) plugins 
$ ibmcloud plugin install container-service -r Bluemix

$ ibmcloud plugin install container-registry -r Bluemix
Enter fullscreen mode Exit fullscreen mode
  • Authorize ibmcloud: 
$ ibmcloud login
Enter fullscreen mode Exit fullscreen mode

Create a Kubernetes cluster and setup Istio

In this section, you will provision a Kubernetes cluster on IBM Cloud Kubernetes service(IKS) and install Istio + Knative components.

$ kubectl apply --filename https://raw.githubusercontent.com/knative/serving/master/third_party/istio-1.0.2/istio.yaml
Enter fullscreen mode Exit fullscreen mode

Install Istio

  • Label the default namespace with istio-injection=enabled: kubectl label namespace default istio-injection=enabled
  • Monitor the Istio components until all of the components show a STATUS of Running or Completed: kubectl get pods --namespace istio-system
  • Follow the instructions for Installing Knative components on IKS cluster
  • To check Knative installation, run the below command 
kubectl api-resources | grep knative
Enter fullscreen mode Exit fullscreen mode

Requires kubectl client version 1.11 or above

To verify Knative installation

Build and Deploy the app

This section uses a rehash of helloworld-nodejs app. For code samples in other programming languages(Go, Python, C#, Java etc.,), refer Knative serving sample applications

  • Clone the repo and cd into the folder 
$ git clone https://github.com/VidyasagarMSC/knative-deploy.git

$ cd knative-deploy
Enter fullscreen mode Exit fullscreen mode
  • Install dependencies 
$ npm install
Enter fullscreen mode Exit fullscreen mode
  • Build and Push the Docker image to IBM Cloud Container Registry by replacing and values 
$ ibmcloud cr build -t registry.<region>.bluemix.net/<namespace>/knative-node-app .
Enter fullscreen mode Exit fullscreen mode

Note: To check your region, run ibmcloud cr regionand to setup a new namespace, refer this link

  • In service.yaml, replace image value and run the below command
$ kubectl apply --filename service.yaml
Enter fullscreen mode Exit fullscreen mode
  • To find the IP address for your service, use kubectl get svc knative-ingressgateway -n istio-system to get the ingress IP for your cluster. If your cluster is new, it may take sometime for the service to get assigned an external IP address. 
$ export IP_ADDRESS=$(kubectl get svc knative-ingressgateway --namespace istio-system --output 'jsonpath={.status.loadBalancer.ingress[0].ip}')
Enter fullscreen mode Exit fullscreen mode
  • To find the URL for your service, use kubectl get services.serving.knative.dev knative-node-app --output jsonpath='{.status.domain}' 
$ export HOST_URL=$(kubectl get services.serving.knative.dev knative-node-app --output jsonpath='{.status.domain}')
Enter fullscreen mode Exit fullscreen mode
  • Now you can make a request to your app to see the result. 
$ curl -H "Host: ${HOST_URL}" http://${IP_ADDRESS}

**Response:** Knative Node App running on IBM Cloud
Enter fullscreen mode Exit fullscreen mode

To Build a source into a container image from a Dockerfile inside a kubernetes cluster and push the image to IBM Cloud Container registry; all of this using Google’s Kaniko tool, follow the steps in the post

Cleanup

  • Run the below command to remove the sample app from your cluster 
$ kubectl delete --filename service.yaml
Enter fullscreen mode Exit fullscreen mode
  • To delete the cluster (removes everything), enter the following command: 
$ ibmcloud cs cluster-rm $CLUSTER_NAME
Enter fullscreen mode Exit fullscreen mode

Questions or concerns? Reach out on Twitter —  VidyasagarMSC

Further reading

💖 💪 🙅 🚩
vidyasagarmsc
Vidyasagar SC Machupalli

Posted on March 14, 2019

Join Our Newsletter. No Spam, Only the good stuff.

Sign up to receive the latest update from our blog.

Related

Install Knative with Istio on IBM Cloud: the hard way
cloud Install Knative with Istio on IBM Cloud: the hard way

March 14, 2019