2. What is Virtualization?
Virtualization is a technique how to
separate a service from the underlying
physical delivery of that service
It was first developed in the 60’s by IBM
Until 1998 it was considered impossible for
microprocessors (x86) based computers
The inventors of x86 virtualization created
VMware in 1998 in Palo Alto
Behind a company, there is an idea!
3. What is Virtualization?
• Virtualization
• Decouples software
from hardware
• Allows multiple
operating systems to
be installed on the
“host” computer
Virtualization
4. 2 Approaches for x86 Virtualization
Hosted: virtualization layer runs as an
application on top of an operating system
Hypervisor (bare-metal): installs the
virtualization layer directly on a x86 based
system
Hypervisor is more efficient, more robust
and has greater scalability and better
performance than hosted architecture
5. Virtualization Layer: VMM
The virtualization layer is responsible for
hosting and managing all virtual machines
VMM (virtual machine monitors) are the
interfaces between the guest operating systems
and the Hypervisor running on the hardware
VMM implement the hardware abstraction
Each VMM has to partition and share CPU,
memory and I/O devices used by the systems
6. The Challenge of x86 Virtualization
x86 (microprocessor) operating systems
are designed to run directly on the
hardware
They assume that they fully “own” the
computer
7. Three Alternative Techniques
Full virtualization using binary translation
Operating system assisted virtualization
(para-virtualization)
Hardware assisted virtualization
8. Virtualization with Binary Translation
Translates kernel code to replace non
virtualizable instructions with new
sequences
Guest OS is not aware of what takes place
9. OS Assisted: Para-virtualization
Modify the guest operating system
(kernel) to replace non-virtualizable
instructions with calls to the virtualization
layer
11. 11
April 13, 2016
What is a Virtual Appliance?
11 04/13/16
VMWareVMWare
ApplicationApplication
Operating SystemOperating System
VMWareVMWare
ApplicationApplication
Operating SystemOperating System
VMWareVMWare
ApplicationApplication
Operating SystemOperating System
An application plus an operating
system, pre-configured, bundled
together. VMware allows multiple
applications to run simultaneously
on a single server.
12. Virtualization with VMware ESX 3.5
Needs a dedicated server !
Each virtual machine represents a complete system – with processor, memory, network interface card,
storage and BIOS
Windows, Linux, Netware etc. with their software applications run totally isolated from each other
Virtual machines see their own private virtual disk files; outside, the virtual disks are simply large files
VMware ESX installs directly on the server hardware, or “bare metal” and inserts
a virtualization layer between the hardware and the operating system
Physical resources such as paging memory are shared between the VM’s on ESX
13. Virtualization with VMware Server
Runs on Windows or Linux as an application
Available for free !
Best choice for test environment on an existing server
Otherwise works like VMware ESX
Editor's Notes
Virtualization allows one computer to do the work of many. It allows multiple OS environments to use/share the physical resources of one server. Virtualization utilizes the hypervisor to decouple the software (OS and applications) from the hardware. The hypervisor allows multiple operating systems to be installed on the “host” computer at the same time. Multiple virtual machines or “guests” run on the host and the hypervisor manages these virtual guests. This configuration allows for tremendous benefits...