The z-series stuff is indeed some amazing piece of kit. Yes, the machine can and does call the technician when something fails. And iirc everything, including

The z-series stuff is indeed some amazing piece of kit. Yes, the machine can and does call the technician when something fails. And iirc everything, including the CPUs, is hot-swappable. That means you can physically remove a CPU-book (containing processors and RAM) and your OS will keep running. Quite a nerds dream, if you have the spare change...