Virtualization began in the 1960s, as a method of logically dividing the system resources provided by mainframe computers between different applications. Since then, the meaning of the term has broadened. <a>
4. What is Virtualization ?
Virtualization is the creation of a virtual (rather than
actual) version of something, such as an operating
system, a server, a storage device or network resources
Virtualization essentially decouples users and
applications from the specific hardware characteristics of
the systems they use to perform computational tasks
Virtualization is a journey …not a project
5. The Four Drivers of Virtualization
Under Utilized Hardware
Data Centers run out of space
Green initiatives demand better energy efficiency
System administration costs mount
6. Traditional Architectures …
One OS one server one application
Tightly coupled hardware and software
Typical load on server is 5 – 15 %
7. Virtualized Architecture
Many OS to one server
Separation between software and Hardware
Many applications on one server
Typical load on server is 80 – 95%
Dynamically optimized resources
16. Application packaging
Here we will try to pack the virtualized environment
along with the application. So that the underlying
hardware and the OS resources will not the attacked
with the malware / virus.
Companies include: SVS from Altriris, Thinstalls’s
virtualization suite, and Microsoft SoftGrid.
17. Application Streaming
Stores the proper versions of applications on servers in
the data centers. Whenever an end user wants to use a
particular application, it’s downloaded on the fly to
the end user’s machine.
Examples include, call centers and office environments
where workers rarely leave the premises to perform
work duties.
18. Hardware emulation
Software representation of the underlying hardware.
Virtualization software is loaded onto a client machine that
has a base operating system already loaded.
It sets a container called “virtual machine”.
Vmware server, Microsoft Virtual server, Macintosh,
SWsoft’s paralles
19. Server Virtualization
Server virtualization is where you use virtual machines
to separate the hardware from the virtual operating
systems, allowing you to run multiple operating
systems on a single computer, all at the same time
Operating System Virtualization
Hardware Emulation
Para virtualization
2
21. OS Virtualization contd..
Each virtual environment has its own
File system
Process table
Networking configuration
System libraries
Provides software emulation
22. OS Virtualization contd….
• Good solution for Software as a Service
– SaaS:
• Software without needing to physically install it.
• Reduces the upfront costs associated with software package
licensing.
• Maintenance headache reduces.
– Google docs
• Advantages:
– Similar set of OS functionalities
– IDEAL for webhosting (high density)
– Training
– Uses set of libraries for OS functionalities and file mapping
services for isolation
– Requires only one license
– Sandboxing
23. OS Virtualization contd….
Limitations:
Choosing the OS
Each container must be the same type, version, and
patch level
Limited to the device drivers
Needs changes in the OS Kernel
Products / Applications:
Virtuozzo and OpenVZ, chroot()
25. Hardware Emulation contd….
Virtualization software – HYPERVISOR
A logical platform to run multiple Operating Systems at
the same time on one host computer.
Emulates hardware environment
Emulated environment – VMM
Guest OS is installed in VM which interacts with VMM
But the guest OS is to be modified - Instead uses
BINARY TRANSLATION
26. Binary Translation
Question: how does the unmodified OS end up making
calls into the hypervisor when it’s actually using calls that
should go straight to the hardware?
Hypervisor substitutes pieces of code within the OS at
runtime in a process called binary translation.
Binary translation occurs in parts of the OS that interact
with the four key resources of the hardware: processor,
memory, network and storage
27. Different approaches to hardware
emulation:
Install Hypervisor directly on the server – bare metal
Hypervisor installed on top of an existing OS
28. Hardware Emulation contd…
Limitation
Performance penalty
Device drivers cannot be installed just like that
It is very slow
Products
VMWare Server and ESX server, Hyper-V, Xen
29. Para Virtualization
As guest OS is to be modified, this is possible for
only open source OS such as Linux, BSD flavors.
Windows cannot ….
Good news is Intel (Intel VT) and AMD (AMD-V)
provide functionality that enables unmodified OS to
be hosted by a para-virtualized hypervisor.
Products
Xen, UML
Shortly – Microsoft Server Virtualization
30. Para Virtualization contd…
Advantages:
No separate device drivers
- uses from Privileged
guest
Very good performance
Multiple different OS can
be supported
Limitations:
Guest OS is to be modified
35. Full Virtualization contd…
• Advantages:
– Better than hardware emulation
– No OS modification required
– Multiple Different OS can be supported
• Limitations:
– OS must support the underlying hardware
• Products
– VMWare, Virtual Box, Xen, Virtual PC (type – II)
36. There is an increase in the shift of business processes
to Web-based digital applications - explosion of data
Problems with this explosion of data
Storage capacity
Having all the data sitting on one physical machine
creates a bottleneck
Backup problems
Storage Virtualization
4
37. Storage Virtualization is the process of abstracting
logical storage from physical storage
Direct Attached Storage
Network Attached Storage
Storage Area Network
The goal of storage virtualization is to group multiple disk
arrays from different vendors, scattered over a network,
into a single storage device
Storage Virtualization
39. Benefits of Virtualization
Production data centres (server consolidation)
– Consolidate servers (especially legacy applications)
– Consolidate desktops
– Make more efficient use of hardware
– Enhance IT staff productivity
Fewer points of admin
Less hardware maintenance and fewer infrastructure
requirements
Faster server deployment
React faster to business needs
Faster Server replacement
41. Benefits of Virtualization
Testing and Development
Disaster Recovery
– Hardware Independence (application portability)
Most hardware selected for a traditional server is
oversized and much of the capacity goes underutilized.
42. Benefits of Virtualization contd..
Reduce IT costs :
Improve Existing Hardware Utilization to reduce costs
Reduce Software license requirements
Leverage scarce IT resources to manage more
Reduce energy costs and drive Green IT initiatives
Improve Management of virtual infrastructure
Business Improvements
Better adapt to business changes
Deliver services on demand
Improve availability of applications
Better secure data and infrastructure for risks
43. Cost Savings!!!
"We estimate that VMware Infrastructure enables
us to avoid $7,500 in hardware and maintenance
costs for each server virtualized.
With 230 virtual machines now running our
business-critical applications on only 18 physical
servers in our Chicago data center, the savings add
up to approximately $1.7 million," said Barry
Naber, technology manager at International
Truck and Engine Corp., a manufacturer of diesel
engines, trucks and school buses.
44. Virtualization Products available
• VMware (EMC)
– VMware Player
– VMware Workstation
– VMware Server 1.x (used to be GSX)
– VMware Infrastructure (VI) 3 (ESX Server)
– VMware Fusion for MAC
– VMware products are feature rich and hold majority market share.
– www.vmware.com
• Microsoft
– Microsoft Virtual PC
– Microsoft Virtual Server
– Microsoft Longhorn - Hypervisor (coming soon)
– All Microsoft Virtualization products are Free Of Cost
– www.microsoft.com/windowsserversystem/virtualserver/default.mspx
45. Virtualization Products available
• VirtualIRON
» VirtualIRON
» It is a challenge to VMware ESX Server
» Offers for less price compared to VMware ESX Server
» www.virtualiron.com
• Parallels for MAC OS
» Parallels Desktop & Workstation
» www.parallels.com
• OpenSource
» Linux Xen
» www.xensource.com
46. Virtualization
AMD-V : Hardware virtualization
Chroot : OS – level virtualization
Bochs : emulation
BSD Jail : OS – level virtualization
Intel – VT : Hardware Virtualization
Linux KVM : Hardware Virtualization
Linux Vserver : OS – level virtualization
OpenVZ : OS – level Virtualization
Qemu : Emulation
User – Model Linux : Paravirtualization
VirtualBox: Full, Hardware virtualization
VMWare : full-virtualization, paravirtualization
Xen : full, paravirtualizaion
SasS = Sales Force.com, Google Dods
PasS = Citrix Xen, VMware vSphare, MS Hyper-V
IasS = Google AppEngine
DaaS = Google
Hardware-Based or Hardware-Assisted Virtualization Approach
The above approach is called “Virtualization Management Layered Approach” .
Notice the host Operating System is called the Host. The host is what talks is hosting the guest Operating Systems.
The host should be large enough to provide the hardware resources necessary for all the guest operating systems.
The virtual machines are dubbed the guest operating systems.
Notice: there is a 5-20% performance penalty for virtualiazing your servers. However, the performance is rarely noticeable if the virtual server is sized properly.
However, the performance penalty where you notice it or not notice it is based on the applications...
The best servers to virtualize and the best applications to virtualize - all servers and applications that are not heavily loaded! they are not high demanding applications. Such as video conferencing and high end sql servers are not good candidates for virtualization.. Light weight file servers and print servers are ideal for virtualization.
Users who are willing to have greater performance can use the “Dedicated Virtualization Approach”.
Instead of the host operating system, we have a virtualization software directly loaded on top of hardware. Since the host operating system is eliminated because of that you can get better performance.
Advantages:
Because there is no host operating system, you will achieve much greater performance out of the virtual machines.
Limitations can be:
The hardware and the virtualization software must be compatible and
you will loose some management features because you have no more host operating system.
Application packaging:
Here we will try to pack the virtualized environment along with the application. So that the underlying hardware and the OS resources will not the attacked with the malware / virus.
Companies include: SVS from Altriris, Thinstalls’s virtualization suite, and Microsoft SoftGrid.
Application Streaming:
Stores the proper versions of applications on servers in the data centers. Whenever an end user wants to use a particular application, it’s downloaded on the fly to the end user’s machine.
Examples include, call centers and office environments where workers rarely leave the premises to perform work duties.
Hardware emulation:
Software representation of the underlying hardware. Virtualization software is loaded onto a client machine that has a base operating system already loaded. It sets a container called “virtual machine”. Vmware server, Microsoft Virtual server, Macintosh, SWsoft’s paralles
OS virtualization :
Is installed in top of an existing OS, provides a set of libraries that applications interact with, giving each application the illusion that it is running on a machine dedicated to its use.
Each set of applications is contained within its assigned virtual OS and cannot interact with other virtual OSes or the applications running in those virtual OSes.
SaaS is the delivery of computing services over the internet, Google’s web searching is a form of SaaS. Google’s search makes it available via a Web page; That same sort of remote execution of application processing is being widely applied to a broad range of business services. – Customer Relationship Management CRM.
Question: how does the unmodified OS end up making calls into the hypervisor when it’s actually using calls that should go straight to the hardware?
Answer:
Hypervisor substitutes pieces of code within the OS at runtime in a process called binary translation.
Binary translation occurs in parts of the OS that interact with the four key resources of the hardware: processor, memory, network and storage
Limitations :
In capturing the calls and redirecting to the OS eats away the machine cycles.
Direct Attached storage:
Traditional mode. Hard drives attached to whatever physical server is running the application.
Easy to use but hard to manage.
Network attached storage:
NAS is a machine that sits on your network and offers storage to other machines. Provides single source of data, facilitating data backup. Uses standard data communication protocols to send data back and forth between a server and the NAS device.
Storage Area Network:
Virtualization is very commonly used in production data centers for consolidating servers.
server consolidation means taking physical servers and consolidating them with virtualization on to single or multiple virtual servers.
This is commonly done on legacy application or older applications that require dedicated servers.
This can also be done with the user desktops too - some companies are taking user desktops, consolidating them on the server and the users access their desktops which is now located on server using thin client device. Instead of working with 100 physical servers lets say and having many administrators to make those physical servers work perhaps consolidate all those servers in to 20 or 25 virtual servers.
require less administration overhead
Less power
Fewer points of administration
Less hardware maintenance to be performed
Fewer infrastructure requirements
Less KVM switches
Less cooling hardware in the data centers
Less power
Fewer UPS requirements
Less Generator
Less space requirements
Faster Server Deployment - that means u can get new server up and going faster
That means You can react faster to the business needs - if the business says you need to buy 10 servers for the business needs - then in the past
you need to buy new rack,
You need to have the ups,
you need to have electricians come and run more electrical wiring,
you need to have the switch
and you need to have new generators to generate more power.
ALL these things might go through your head.
But with virtualization, you can run 10 new servers on 1 or 2 physical server.
Faster server replacements - Lets say any server goes down or you are replacing hardware - its much easier to replace the servers if they are virtualized.
Network isolation of your network
You can download entire applications that are preinstalled - it might have taken days and weeks to install but you can have that application pre-installed, all you need to do is you download and get it up in matter of minutes.
disaster recovery - as your servers are virtualized - those are single files that can be backed up and then restored 0r even transmitted across a wide area network. in case of disaster recovery, those virtualization servers are easily set up on any other virtualized server with the same virtualization software - so, you don’t have to have any dedicated physical servers.
This provides you hardware independence and also Application portability.
IT decision makers face continually escalating data center infrastructure and administrative costs from hardware acquisition, management, power and cooling, real estate and disaster recovery. VMware Infrastructure is designed to help customers reduce these costs by turning industry-standard hardware into OS- and hardware-agnostic enterprise-class virtual infrastructure. The software suite is designed to allow entire server, storage and network farms to be managed as a shared utility and dynamically allocated to different business units or projects. Using the VMware TCO Calculator, customers now can quickly estimate the potential savings of implementing VMware Infrastructure as a core element of their IT architecture.
Out of all the products, VMware is the market leader and got huge market share in virtualization products!
Hypervisor is included in windows 2008 Server Build-in (Read more)
