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Glossary
Domain
A configurable set of resources, including memory, virtual CPUs, network devices and disk devices, in which virtual machines run. A domain is granted virtual resources and can be started, stopped and rebooted independently.
See also dom0 and domU.
dom0
An abbreviation for domain zero. The management domain with privileged access to the hardware and device drivers. Dom0 is the first domain started by the Oracle VM Server at boot time. Dom0 has more privileges than domU. It can access the hardware directly and can manage the device drivers for other domains. It can also start new domains.
domU
An unprivileged domain with no direct access to the hardware or device drivers. Each domU is started by Oracle VM Server in dom0. The xm
Guest
A guest operating system that runs within a domain in Oracle VM Server. A guest may be paravirtualized or hardware virtualized. Multiple guests can run on the same Oracle VM Server.
Hardware virtualized machine
A virtual machine with an unmodified guest operating system. It is not recompiled for the virtual environment. There may be substantial performance penalties running as a hardware virtualized guest. Enables Microsoft Windows™ operating system to be run, as well as legacy operating systems. Hardware virtualization is only available on Intel VT or AMD SVM CPUs.
Host computer
The physical computer on which Oracle VM Server is installed.
Hypervisor
The hypervisor, monitor, or Virtual Machine Manager (VMM). It is the only fully privileged entity in the system. It controls only the most basic resources of the system, including CPU and memory usage, privilege checks, and hardware interrupts.
Management domain
See dom0.