How to identify the dom0 Version (Oracle VM Server Version) from a Virtual Machine

Question: How to identify the dom0 Version from a Virtual Machine?

The DMI output in the dmesg commands tells about the dom0 version

Oracle VM 3.4.x

[ 0.000000] DMI: Xen HVM domU, BIOS 4.4.4OVM 08/15/2018

Oracle VM 3.3.x

[ 0.000000] DMI: Xen HVM domU, BIOS 4.3.1OVM 06/24/2015

Oracle VM 3.2.x

[ 0.000000] DMI: Xen HVM domU, BIOS 4.1.3OVM 06/03/2013

Note, there might be slight differences in the last digit of the Oracle VM version, for example, 4.1.3OVM might become 4.1.4OVM. The 4.x.x versions are the Xen version installed and from that, it is possible to determine the Oracle VM version.

dmidecode can be used as well to identify them:

# dmidecode -s system-product-name
HVM domU
# dmidecode -s system-version
4.4.4OVM
# dmidecode -s bios-release-date
08/15/2018
# dmidecode -s bios-version
4.4.4OVM

Similar outputs are available for:

Microsoft Hyper-V

[ 0.000000] DMI: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v1.0 11/26/2012

VMware Workstation

[ 0.000000] DMI: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/02/201

VirtualBox

[ 0.000000] DMI: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006