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