[bdndndndbve]

I would want to have at least dev + prod clusters, sometimes people want to test controllers or they have badly behaved workloads that k8s doesn't isolate well (making lots of giant etcd objects). You can also test k8s version upgrades in non-prod.

That said it sounds like these people just made a cluster per service which adds a ton of complexity and loses all the benefits of k8s.

[withinboredom]

In this case, I use a script to spin up another production cluster, perform my changes, and send some traffic to it. If everything looks good, we shift over all traffic to the new cluster and shutdown the old one. Easy peasy. Have you turned your pets into cattle only to create a pet ranch?