Can it discover and report: AS400, iPower, AIX, VAX, HP3000/9000, VMware, etc...
We have audit scripts for AIX and ESXi (as well as Linux, Windows, OSX, etc).
Discovery will detect anything with an SSH port open and try to interrogate the device.
I have no access to AS400, iPower, VAX or HP3000/9000 machines so I cannot test commands. You are most welcome to supply the required commands and their resulting output and I can integrate it into Discovery. If you would like complete audit scripts to be created, we can certainly arrange something. That's what we did for the AIX script (a customer request).