Find out if the OS is running in a virtual environment

Question

Is there any way to find out if the OS i'm running (actually installing) is running in a VMWare machine. I need to disable ntp settings if the automated install is done on a virtual machine but keep them enabled if installing on bare metal.

Answer 1

Using dmidecode or lshw and greping seems to be to be the best way to find out.

Answer 2

If all you need is a way to tell whether the OS/host is a virtualized host or not, just you have a perl module Sys::Detect::Virtualization and the script with it virtdetect. It does all the possible heuristics/guess detections and reports the detected OS environment. Give it a try.

http://search.cpan.org/dist/Sys-Detect-Virtualization/script/virtdetect

Answer 3

You could try Joanna Rutkowska's Red Pill This little program examines the IDTR (interrupt descriptor table register) using the SIDT instruction (x86 only), which apparently will be set differently by different VMMs.

Answer 4

The best idea would probably to look at the hardware. At least with VirtualBox you can easily determine that you are on a virtual machine, due to the names of some of the hardware devices (for example /sys/block/sda/device/model will say "VBOX HARDDISK").

Since all your machines are VMware, just pick one of those things and check that.

Answer 5

Linux adds the hypervisor flag to /proc/cpuinfo if the kernel detects running on some sort of a hypervisor.

Answer 6

well, the most intuitive way I always do is:

$ dmesg | grep -i vmware