COMP 4923 A2Virtualization 1

Danny SilverJSOCS, Acadia University

The Server Invasion

• The Invasion - IBM Virtualization Engine -http://www.youtube.com/watch_popup?v=Kbn_MUfTG0E#t=15

Size of the Web (Darcy Benoit)

• Web servers are approximately 0.56% of the total number of IP addresses (4.3 billion), or 0.64% of the "valid" usable IP addresses (3.8 billion)

• If we could put one server every foot, the web servers would span from St. John's, NFLD to Victoria, BC

• If each server used only 100 Watts of power:– The equivalent of 3.275 Advanced CANDU 6 nuclear reactors (each CANDU 6

= 740 MegaWatts)

• If each server used 500 Watts of power:– That is 16.375 Advanced CANDU 6 nuclear reactors– Or more than half of the electricity produced by the Three Gorges Dam in

China, the world's largest hydroelectric dam (gross output = 22,500MW, $39 Billion and 17 years to build)

What is Virtualization?

• Perhaps the most important step for modern data centers in terms going Green by reducing energy and costs

• Provides tremendous flexibility and increase availability and reliability

• There are many variants of virtualization …– Wikipedia - http://en.wikipedia.org/wiki/Virtualization

What is Virtualization?

• Great intro by VMWare - http://www.youtube.com/watch_popup?v=MnNX13yBzAU

• Slightly more complex intro - http://www.youtube.com/watch_popup?v=p11lJOnALS4&pop_ads=null

• Cool 60's-like overview - http://www.youtube.com/watch_popup?v=57XDSrwEdRg

What is Virtualization?

• There are many variants of virtualization …– Wikipedia - http://en.wikipedia.org/wiki/Virtualization

Client/Server History: 1980Centralized DP, DS, DC

IBM Mainframe

Frontend

3174 Controller

Dumb3270 DisplayScreen

SNA

Client/Server History: 1990Decentralized DP, DS, DC

Mainframe orMini-Computer

FrontendHardware

PC Local DP, DS, Low speed DCTerminal Emulation

LAN Controller

LAN Controller

TCP/IP File I/O and Terminal Emulation

Client/Server History: 2000Distributed DP, DS, DC

Mainframe, Mini-Computer or

Servers

FirewallThick ClientWeb / InternetDistributed DP, DS, Mod speed DCPeer-to-Peer

Internet

LAN Server

LAN Server

Client/Server History: 2005Mixed Centralized / Distributed

Rows and Racks of Internet Servers

Early Thin ClientWeb / InternetDistributed Applications DP, DS, High speed DC

LAN

LAN

Internet

Client/Server History: 2010Centralized Virtual Clients

Rack-mounted Multi-core

Virtual Servers

Thin ClientWeb Inter-operativePresentation DP, Higher Speed DC+ Wireless

LAN

LAN

Internet

Internet / Processor Speeds are Key Factors

• Most significant factors in centralized/ distributed computing:– Dial-up (9600 bps - 1 Mbps)

• Processing must be done at mainframe

– LAN (10 Mbps)• Decentralized processing and display with file /IO

– High-speed LAN (100 Mbps)• Distributed computing and local display

– High-speed, parallel (multi-core) processing• Virtualization

Consolidation

APP1

OS 1H/W

APP2

APP3

OS 1H/W

APP4

APP5

OS 1H/W

APP6

OS 1H/W

APP1

APP2

APP3

APP4

APP5

APP6

Each server10% busy2 kW power

ConsolidatedServer 60% busy4 kW power

OS 1 must beactive for allapps.

Full Virtualization

APP1

WinH/W

APP2

APP3

LinuxH/W

APP4

APP5

UnixH/W

APP6

H/W

APP1

APP2

APP3

APP4

APP5

APP6

Each server10% busy2 kW power

VirtualizationServer 60% busy4 kW power

Win Linux UnixHypervisor

Hypervisorcreates and maintains a virtual machine

Impact in the Data Center is Huge

• Separate servers require:– Network infrastructure: NICS, cables, switches– Separate disk drives– Limited by disk I/O and cable speeds (Mbps)

• Virtualized servers require:– None of the above– Share disk drives– In-memory data transfer speeds (Tbps)

Virtualization System Vendors and Products

• IBM – System z/VM, System p/Hypervisor• VMWare – VMware Server, Vmware ESXi • MicroSoft – MS Hyper-V Server• Xen – Open source hypervisor

• Also see this Wikipedia list of hypervisors

• Not a new concept – see IBM CP/CMS (1962)

Cutting Edge Hardware R&D

Advantages of Server Virtualization and Centralization

• Disaster recovery– Server state is always in a file, just recover to

check-point

• Flexibility– Server creation, mods and movement on the fly

• Reduced energy use lower carbon footprint– One server versus 10– Less cooling needed

Advantages of Server Virtualization and Centralization

• Reduced operational costs– Care for 1 larger server versus 10 smaller servers

• Better support for users– One stop help desk for all server users

• Greater availability– Hot standby made easy

• Improved reliability– High quality server components can be purchased

and shared

Partitioning

• A tool used to support virtualization• Ability to pool resources (CPU, memory, I/O)

into a single logical computer, or logical partition (LPAR)

CPU

RAMDisk

I/O

CPU

RAMDisk

I/O

CPU

RAMDisk

I/O

LPAR 1 (Windows)

LPAR 2(Linux)

A Virtual Machine is a File

• An LPAR can be completely defined in a file

• This means that the state of a virtual machine can be saved and moved easily, even on the fly

• Vmware offers Vmotion– Decrease downtime and improve reliability– Decrease energy use by dynamically powering down unused servers– Reduce IT costs and improve flexibility

CPU

RAMDisk

I/O

File

Network Virtualization

• VMware ESX and IBM System p (Live Partition Mobility)• Network is virtualized = virtual machine

retains network identity (IP address) and connections

• Ensures seamless migration of LPARs from one physical server to another over high-speed physical network

Paravirtualizatoin

• Xen (open source) full or “paravirtualization”• Full virtualization approach:

– OS is not aware that its is running on a virtual machine– H/W and hypervisor handle all virtualization

• Partial “para” approach:– OS must be aware that its is running on a virtual machine– OS works with hypervisor to handle virtualization– Some restrictions of OS function

Operating System Level Virtualization

• One operating system per physical machine• Example: SUN Solaris containers• OS is capable of making virtual instances of

itself• Great for consolidation of e-mail and web

servers• Limitation: can only be used by apps that run

on that generation of OS

SAN – Storage Area Network

• A dedicated network of data storage hardware and software

• Integrates various storage devices: disks, arrays, CD towers, magnetic tape drives, I/O connect services

• Software manages all physical storage resources into one logical storage resource

• Shared access across various servers• High inter-connection rates between storage devices

and servers• Tape backup / recovery can also be virtualized

Client Virtualization

• Estimated savings if desktops replaced by thin clients: 60% energy, 50% costs

• Installed PCs show very low average use rate• Try monitoring your laptop (CTRL-ALT-DEL)

– Search disk for “supercalifragilisticexpialidocoius”– Download a large file from the web– View a YouTube video– Run a complex calculation or CPU stress tester

Client Virtualization

• Benefits:– Low cost of ownership (purchase, energy)– Low cost of maintenance (centralized)– Security (logins are never local, always monitored)– Reliability (boot image control)– Common knowledge pool

• Consequents:– Loss of flexibility– Loss of multi-media performance on some tasks

Blade Servers

Why use blade system servers?

Blade Servers

• Standard server-rack configuration:– 1RU (one rack unit, 19" [48 cm] wide and 1.75" [4.45 cm] tall)– Typically a rack can hold 42 RUs, or 42U high

• Blade server:– Stripped down server computer with a modular design optimized to

minimize the use of physical space and energy.

• Blade enclosure: • holds multiple blade servers• provides services such as power, cooling, networking

• Densities of up to 128 discrete blade servers per rack (2009)

Blade Servers

• Reduces complexity of IT components• Modular and flexible platform• Hardware counter-part to virtualization• Economizes on space, power, cooling,

management• Comes with strong management tools• Suppliers: HP, IBM, SUN/Oracle• But as of 2007 still only 5% of server market

Combining Blades and Virtualization

• Increased utilization, reliability, flexibility and serviceability

• IT Admins spend less time managing and reorganizing physical data centre

• Moves a step closer to dynamic IT or utility computing

• Backbone of cloud computing