Unpopular opinion incoming

As an Infrastructure Architect myself, I hear a lot of people talking about cloud architecture as if it’s some super secret discipline that only those who have been inducted into the cloud cabal could possibly comprehend.

It’s not. It does require an understanding of the differences of course, and those differences will affect your design and where you decide to host a system, but the fundamental components of both are very similar and if you’re doing it right your tooling should largely cover both. If you can design a good infrastructure platform, you can do it regardless of where you need to run it.

But the cloud is different

Is it? It’s still the same components, there’s VMs and containers and firewalls and load balancers, and some further abstractions like serverless functions (which still run on a server, you just don’t see it). The payment model is different, as is your access behind the curtain, but you’re still stringing together compute, memory and storage to power an application. The cloud forces you to use higher-level tools, because you can’t drop to a shell and poke a configuration file in the same way you can on a server, but shouldn’t your configuration management be handling that anyway?

Much in the same way we took the capabilities of virtualization and used them to help manage our bare-metal machines many years ago, modern on-premise platforms look very much like their public cloud counterparts. Products like Nutanix and Openshift give a very cloud-like experience in your datacenter, and management tools like Ansible, Terraform or Tanium work with pretty much everything.

Ha! So it is different

There are differences in capability and cost profile, but the design process shouldn’t change. You take the overall requirements for the application and the business needs and see where it fits, the same as you would do when choosing the operating system or storage platform. The role of the Infrastructure Architect is to consider the technical requirements of the desired system and the wider needs of the business and produce the design accordingly.

An On-Prem system would look nothing like a cloud based solution

Let’s look at a simple system and see how similar they could be.