Shared Auth For Multiple App Instances (microservice architecture)

[Beetroit]

Hi @pgjones, i'd like an example of how to share auth state (not sure this is the right term). Lets say I have 3 instances of the same application running as part of a Docker Compose setup, for scalability purposes. Each one is behind an nginx load balancer. If a user logs in on one server, and on their next request, nginx routes them to another server, will the auth state persist? If not (which I assume to be true), how do I implement a way to share state? Say Redis, for instance, or Memcached.