Book Image

Hands-On Cloud Development with WildFly

By : Tomasz Adamski
Book Image

Hands-On Cloud Development with WildFly

By: Tomasz Adamski

Overview of this book

The book starts by introducing you to WildFly Swarm—a tool that allows you to create runnable microservices from Java EE components. You’ll learn the basics of Swarm operation—creating microservices containing only the parts of enterprise runtime needed in a specific case. Later, you’ll learn how to configure and test those services. In order to deploy our services in the cloud, we’ll use OpenShift. You’ll get to know basic information on its architecture, features, and relationship to Docker and Kubernetes. Later, you’ll learn how to deploy and configure your services to run in the OpenShift cloud. In the last part of the book, you’ll see how to make your application production-ready. You’ll find out how to configure continuous integration for your services using Jenkins, make your application resistant to network failures using Hystrix, and how to secure them using Keycloak. By the end of the book, you’ll have a functional example application and will have practical knowledge of Java EE cloud development that can be used as a reference in your other projects.
Table of Contents (14 chapters)

Load balancing

We have just learned how to scale our service. The next natural step is to configure the load balancer. The good news is that OpenShift will do most of the stuff automatically for us.

In Chapter 6, Deploying Applications on the Cloud with OpenShift, where we introduced services, we learned that a service is reached using a virtual cluster IP. To understand how load balancing works, let's understand how cluster IP is implemented.

As we have also learned here, each node in a Kubernetes cluster runs a bunch of services, which allow a cluster to provide its functionality. One of those services is kube-proxy. Kube-proxy runs on every node and is, among other things, responsible for service implementation. Kube-proxy continuously monitors the object model describing the cluster and gathers information about currently active services and pods on which those services...