Big Shift

The end of the road is nothing like nigh for Google's Kubernetes container orchestrator, reflected not least in sheer numbers: The May 2019 KubeCon saw 7,700 participants. Clearly, no manufacturer can ignore Kubernetes without being considered out of the loop.

A veteran like Red Hat certainly can't afford that perception, which is why they launched OpenShift at an early stage. OpenShift is an open source container application platform that, according to the manufacturer, is particularly easy to roll out and operate. Recently, Red Hat launched OpenShift 4. Of course, this version is bubbling with new features and far better than all its predecessors together – if you believe Red Hat's PR department.

However, does the product deliver what the manufacturer promises? How does OpenShift fit into Red Hat's cloud strategy? I look at precisely these questions in this article.

The Idea

Red Hat describes OpenShift as a Platform as a Service (PaaS), which in itself points toward a development that has been going on for years: the fragmentation of the individual layers of the IT landscape. Whereas customers used to obtain their complete environment from a single source, today they usually have to deal with several providers. The challenge is to enable the various providers to work together across standardized interfaces.

What sounds complicated in theory is far easier in practice. At the bottom of the stack are the platform providers, because even in times of serverless computing, someone has to run the servers that allow customers to do without their servers. Providers usually offer some form of Infrastructure as a Service (IaaS), often combined with a few as-a-service offerings like Database as a Service because – and the providers are aware of this – if you only want to run a web application, you will not want to worry about running a database.

Classic IaaS is now mostly based on virtual machines (VMs), which come with plenty of overhead.

Docker for All

Docker identified the overhead weakness years ago. Without further ado, VMs were given support from containers based on existing kernel functionality. They have far less overhead and allow programmers to write cloud-native applications – the opposite of the conventional consolidation approach. Applications are no longer big and monolithic; instead, they are divided into microservices distributed across many containers.

For this setup to work, however, an instance must manage those containers. Google's Kubernetes has developed into the apparent market leader. Accordingly, Kubernetes is the layer based on classic IaaS offerings and thus enables the efficient operation of cloud-native-style apps (Figure 1).

Figure 1: Kubernetes is part of the "agile revolution" and enables the operation of cloud-native applications (Kubernetes authors, CC BY 4.0 [1]).

Most developers of applications will not want to deal with Kubernetes and the operation of the platform itself. What they really want is a kind of Kubernetes as a Service, a product that rolls out Kubernetes on a predefined infrastructure at the push of a button and that makes running your own applications in this infrastructure as easy as possible.

Red Hat is seeking to exploit exactly this niche with OpenShift. Although OpenShift has existed as a PaaS platform for more than eight years, Red Hat did not make the radical shift to Kubernetes until it was mature and proven for production.

Red Hat products cover all the other parts of the modern data center, as well. If you run OpenStack, you can use the Red Hat OpenStack Platform. If you need CloudForms, you can get it as a boxed product. In all of these cases, Red Hat Enterprise Linux (RHEL) acts as the basis for all of the products.

Three Variants

Red Hat still offers three variants of OpenShift. The OpenShift Container Platform is easy to roll out in a data center. If you want an OpenShift managed by Red Hat in Amazon Web Services (AWS), instead, you will opt for OpenShift Dedicated. OpenShift Online, which Red Hat also hosts, stands out from the crowd by giving users access to an OpenShift platform on demand, and paying only for the resources actually needed.

The advantages and disadvantages of the individual variants are discussed in detail later in this article. For the time being, however, the focus is on the on-premises variant – that is, OpenShift Container Platform.