Cluster local issue with Knative Eventing v0.9.0

In my previous post, I talked about Knative v0.9.0 and some of the eventing changes in the latest release. I’ve been playing with Knative v0.9.0 since then to read Google Cloud Pub/Sub messages using PullSubscription and I ran into a rather fundamental issue that baffled me for a while. I’d like to outline the problem and the solution here, just in case it’s useful to others. Knative Services as eventing sinks In my PullSubscription, I could define Kubernetes Services as event sinks as follows: [Read More]

Migrating from Kubernetes Deployment to Knative Serving

When I talk about Knative, I often get questions on how to migrate an app from Kubernetes Deployment (sometimes with Istio) to Knative and what are the differences between the two setups. First of all, everything you can do with a Knative Service, you can probably do with a pure Kubernetes + Istio setup and the right configuration. However, it’ll be much harder to get right. The whole point of Knative is to simplify and abstract away the details of Kubernetes and Istio for you. [Read More]

Application metrics in Istio

The default metrics sent by Istio are useful to get an idea on how the traffic flows in your cluster. However, to understand how your application behaves, you also need application metrics. Prometheus has client libraries that you can use to instrument your application and send those metrics. This is good but it raises some questions: Where do you collect those metrics? Do you use Istio’s Prometheus or set up your own Prometheus? [Read More]

Istio Routing Basics

When learning a new technology like Istio, it’s always a good idea to take a look at sample apps. Istio repo has a few sample apps but they fall short in various ways. BookInfo is covered in the docs and it is a good first step. However, it is too verbose with too many services for me and the docs seem to focus on managing the BookInfo app, rather than building it from ground up. [Read More]

Istio 101 (1.0) on GKE

Istio 1.0 is finally announced! In this post, I updated my previous Istio 101 post with Istio 1.0 specific instructions. Most of the instructions are the same but with a few minor differences about where things live (folder names/locations changed) and also most commands now default to kubectl instead of istioctl. For those of you who haven’t read my Istio 101 post, I show how to install Istio 1.0 on Google Kubernetes Engine (GKE), deploy the sample BookInfo app and show some of the add-ons and traffic routing. [Read More]

Istio 101 (0.8.0) on GKE

In one of my previous posts, I showed how to install Istio on minikube and deploy the sample BookInfo app. A new Istio version is out (0.8.0) with a lot of changes, especially changes on traffic management, which made my steps in the previous post a little obsolete. In this post, I want to show how to install Istio 0.8.0 on Google Kubernetes Engine (GKE), deploy the sample BookInfo app and show some of the add-ons and traffic routing. [Read More]

Codemotion in Amsterdam, Devoxx in London

After my trip in Istanbul, I visited my parents in Nicosia, Cyprus for a long weekend. Then, I stopped by in Amsterdam for Codemotion before coming back to London for Devoxx 4 cities in 4 countries in 1 week was exhausting but also a lot of fun in many ways. Codemotion Amsterdam Amsterdam is almost a second home to me nowadays. There’s a great tech scene and a lot of tech events throughout the year, as a result, I end up visiting Amsterdam at least 2–3 times a year. [Read More]

Istanbul: The city where the East and the West meet

Istanbul is one of those crazy dynamic cities with friendly people, amazing history, great shopping and above all, a food heaven. Naturally, I was excited to be back for Java Day Istanbul conference. I came a day early to meet with a partner and visit a customer. They had lots of questions on Kubernetes and hybrid-cloud. It was quite useful for me to hear about their challenges about moving to the cloud and propose some solutions. [Read More]

Istio 101 with Minikube

As part of my Istio 101 talk, I like to show demos locally (because conference Wifi can be unreliable) and Minikube is perfect for this. Minikube gives you a local Kubernetes cluster on top of which you can install Istio. In this post, I want to show how to do Istio 101 on Minikube. More specifically, I will show how to install Istio, deploy a sample application, install add-ons like Prometheus, Grafana, Zipkin, ServiceGraph and change traffic routes dynamically. [Read More]

Trip Report: Codemotion in Rome

Last week, I was in one of my favorite cities, Rome, for Codemotion conference. There are many cities to see in the world and normally, I do not like to revisit cities that I’ve been before. However, Rome is a great exception. It was my fifth visit there over the years and it was still as exciting as the first time. I also found out that Google has a small office in Rome, so I paid a quick visit next morning before attending the conference. [Read More]