Yes. Mainframes still exist. IBM still sells them, and you can do things like hotswap CPUs and RAM or setup an geographically distributed HA cluster that can sw

Yes. Mainframes still exist. IBM still sells them, and you can do things like hotswap CPUs and RAM or setup an geographically distributed HA cluster that can swap which mainframe the VMs or databases are "running" on without dropping connections, requests, or other interruptions. https://en.wikipedia.org/wiki/IBM_Z https://en.wikipedia.org/wiki/IBM_Z