How to identify that you're running under a VM?

Question

Is there a way to identify, from within a VM, that your code is running inside a VM?

I guess there are more or less easy ways to identify specific VM systems, especi

Answer 1

You might be able to identify whether you're in a virtual machine by looking at the MAC address of your network connection. Xen for example typically recommends using a specific range of addresses 00:16:3e:xx:xx:xx.

This isn't guaranteed as it's up to the administrator of the system to specify what MAC address they like.