Defining a Zero-Downtime Deployment

Updating a single-replica MongoDB cannot demonstrate true power behind Deployments. We need a scalable service. It’s not that MongoDB cannot be scaled (it can), but it is not as straight-forward as an application that was designed to be scalable. We’ll jump to the second application in the stack and create a Deployment of the ReplicaSet that will create Pods based on the vfarcic/go-demo-2 image.

Zero-downtime deployment is a prerequisite for higher frequency releases.

Looking into the Definition

Let’s take a look at the Deployment definition of the API.