I want to be able to perform a real immutable software upgrade on a K8S cluster, in K8S cluster nodes, like upgrading the version of docker or podman, that, whithout stopping the running app deployed inthe cluster
I also want the exact same case, except there is an app,behind a simple load balancer, balancing over 3 VMSwhere the app is deployed, you that kind of stateful ld style load balancer, something like with HA Proxy and redis to save to session to (like oauth2-proxy which has option to user redisfor sessions)
finally I want the blunt case of one single VM, a backup restore all automated so that the interruption of service is as short as possible.
oauth2-proxywhich has option to user redisfor sessions)