The primary use case for Rubrik is backup and restore and as an archival system. We use it for backup and restore for virtual machines, managed volumes that are mounted and which we use for snapshots from Rubrik to endpoint devices, NAS shares from our Isilon system, as well as SQL databases, Oracle Databases, and Windows and Linux. We may have some failover cluster Windows shares going to it. It's for backups and restores of pretty much everything. It works really well in concert with Pure Storage technology. We have a really large Pure Storage environment and they play really well together.
The solution is on-prem and it's protecting environments that are on-premises exclusively at this point, although we have plans to push towards the cloud. Most of it is virtual but I'd be surprised if we didn't have at least half-a-dozen physical machines connected to it.