Managing Domains
any instruction is executed which would violate the isolation with other guests or dom0. In the current implementation, there may be performance penalty for certain types of guests and access types, but hardware virtualization also allows many Microsoft Windows™ operating systems and legacy operating systems to run unmodified.
2.4 Management Domain
Most of the responsibility of hardware detection in a Oracle VM Server environment is passed to the management domain, referred to as domain zero (or dom0). The dom0 kernel is actually a complete Linux kernel with support for a broad array of devices, file systems, and software RAID and volume management. In Oracle VM Server, the dom0 is tasked with providing access to much of the system hardware, creating, destroying and controlling guest operating systems, and presenting those guests with a set of common virtual hardware.
2.5 Domains
Domains other than the management domain (dom0) are referred to as domU. These domains are unprivileged domains with no direct access to the hardware or device drivers. Each domU is started by Oracle VM Server in dom0.
2.6 Hardware Virtualization Vs. Paravirtualization
Oracle VM Server uses paravirtualization, not binary translation. That is, the source code of the operating system is modified to support virtualization.
Binary translation is neither faster, nor slower, than hardware virtualization. Whether binary translation or hardware virtualization is more efficient than paravirtualization depends on the implementation of the binary translation and hardware virtualization, and the applications and operating system running as a guest on the system.
Binary translation and hardware virtualization, is required if you are using an operating system where it is impractical to do paravirtualization, for example, if the source code is not available such as for Microsoft Windows™, or the user base is not large enough to sustain a paravirtualization effort such as for the Linux 2.4.x kernel. In many situations, paravirtualization may perform better than binary translation as operations that cause a hypervisor interaction can be grouped and reused, rather than each event requiring its own hypervisor interaction.
2.7 Creating Virtual Machines
Create virtual machines (guests) using the Oracle VM Server
2.8 Managing Domains
Manage domains using the Oracle VM Server xm
Migrate domains using the xm migrate command. See Chapter 6, "Domain Live Migration" for more information.
Oracle VM Server
