Because of performance, especially regarding being able to use a battery-backed write-back cache on the controller to give a "safe in the event of powerfailure" confirmation to the application before it actually hits disk/flash.
The "can't read from any other machine" is handled by making sure (this includes testing) that the volumes are readable with dmraid. At least that's for SAS/SATA applications. I'm not sure about NVMe, as it uses different paths in the IO subsystem.
> Because of performance, especially regarding being able to use a battery-backed write-back cache on the controller to give a "safe in the event of powerfailure" confirmation to the application before it actually hits disk/flash.
Is this not easily mitigated with a smart UPS? (i.e., one that will notify the host when the battery is low so it can shut down cleanly)
The "can't read from any other machine" is handled by making sure (this includes testing) that the volumes are readable with dmraid. At least that's for SAS/SATA applications. I'm not sure about NVMe, as it uses different paths in the IO subsystem.