Book Image

Learn OpenShift

By : Denis Zuev, Artemii Kropachev, Aleksey Usov
Book Image

Learn OpenShift

By: Denis Zuev, Artemii Kropachev, Aleksey Usov

Overview of this book

Docker containers transform application delivery technologies to make them faster and more reproducible, and to reduce the amount of time wasted on configuration. Managing Docker containers in the multi-node or multi-datacenter environment is a big challenge, which is why container management platforms are required. OpenShift is a new generation of container management platforms built on top of both Docker and Kubernetes. It brings additional functionality to the table, something that is lacking in Kubernetes. This new functionality significantly helps software development teams to bring software development processes to a whole new level. In this book, we’ll start by explaining the container architecture, Docker, and CRI-O overviews. Then, we'll look at container orchestration and Kubernetes. We’ll cover OpenShift installation, and its basic and advanced components. Moving on, we’ll deep dive into concepts such as deploying application OpenShift. You’ll learn how to set up an end-to-end delivery pipeline while working with applications in OpenShift as a developer or DevOps. Finally, you’ll discover how to properly design OpenShift in production environments. This book gives you hands-on experience of designing, building, and operating OpenShift Origin 3.9, as well as building new applications or migrating existing applications to OpenShift.
Table of Contents (24 chapters)

HA in OpenShift

In the previous chapters, we ran our applications on a single node, or sometimes, two nodes. Some might say that if there is more than one OpenShift node in the cluster, it is considered a redundant configuration, but that is far from true.

If we compare standard OpenShift architecture and OpenShift HA, you will see some differences between them:

OpenShift classic architecture

Here we have nodes, masters, storage, and a routing layer consisting of infra nodes. OpenShift HA architecture is quite similar but has one distinct difference—in the routing layer we have load balances that make the overall solution always accessible. All other components are redundant by nature:

OpenShift HA architecture

Virtual IPs

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