We're currently quite off-topic if i'm honest. I think the author was specifically talking about RAID-1 redundancy and is advocating that you can leave your sy

We're currently quite off-topic if i'm honest. I think the author was specifically talking about RAID-1 redundancy and is advocating that you can leave your systems with RAID-0 (so no redundant drives in each server), as you're gonna need multiple nodes in your cluster anyway... so if any of your systems disks break, you can just let it go down and replace the disk while the node is offline. but despite being offtopic: redundant implementations are -from my experience - not used in a failover way. they're active at all times and load is spread if you can do that, so you'd likely find the inconsistencies in the integration test layer.