Rolling Deployment

A rolling deployment strategy is a minor variation of the in-place rolling update deployment strategy. In this strategy, the new application replaces the older version by completely replacing the infrastructure rather than overwriting it. In the diagram below, imagine we have three containers running the current application (V1). In rolling deployment, the new version (V2) is installed by swapping the old container with a new one.

Deployment steps

An essential prerequisite of the rolling deployment is if the business requirement is to run $N$ instances of our application in production, then we need $N + 1$ ...