Software-Layer Abstraction: Virtual Machines - Compaq BL10e - HP ProLiant - 512 MB RAM Introduction Manual

Figure 1. HP technologies for machine abstraction include Virtual Connect, integrated hypervisors, and integrated
management.

Software-layer abstraction: virtual machines

In a virtual machine environment, a software layer abstracts the physical server hardware and creates
one or more virtual machine instances, each with its own virtual drives, virtual network interface
controllers (NICs), virtual storage controllers, virtual processors, OS, and application(s). The software
abstraction layer is typically referred to as a hypervisor or a virtual machine monitor. An OS that runs
in the virtual machine instance is called a guest OS.
On a single physical platform, the software abstraction layer can create one or more virtual
machines. These virtual machines share the physical resources (Figure 2). In today's data centers,
servers often run single workload instances and are sometime under-utilized in off peak hours. By
moving these workloads onto virtual machines, administrators can consolidate under-utilized
hardware, and better utilize the server hardware while still maintaining OS and application isolation.
3