Virtualization and Disaster Recovery Ray Trygstad Director of Information Technology, Associate Director, Information Technology & Management Degrees Illinois Institute of Technology NetSecure 09 March 12, 2009
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What is Virtualization? A broad term referring to the abstraction of computer resources As well as operating systems (the focus of this course) we can virtualize Storage Applications In fact, we can virtualize any hardware or software component of an information system 3
What is Virtualization? Can make one physical resource appear as one logical resource, or Multiple physical resources can appear as one logical resource (clustering, grid computing, multidisk storage virtualization), or One physical resource can appear as multiple logical resources (OS virtualization, hard drive drive volumes) 4
Operating System Virtualization The creation of a virtual machine (VM) using a combination of hardware and software Also known as platform virtulization Not a new technology! Originally designed/implemented by IBM in the mid-1960 s M44/44X, CP-40, CP-67, IBM VM 5
Operating System Virtualization In platform virtualization, a host system or host machine runs an application that allows the creation and operation of a simulated physical computer environment An instance of this simulated or emulated environment is called a virtual machine or (for brevity) a VM 6
OS Virtualization Definitions Operating System Virtualization A computer running within a computer, implemented in software; allows the decoupling of hardware from the operating system Virtualization Software A computer application that allows a virtual machine a virtual representation of a real computer to run on a physical computer system 7
OS Virtualization Definitions Host Machine Physical machine running virtualization software; contains physical resources memory, storage, processor and more plus other resources network access, for example used by virtual machines 8
OS Virtualization Definitions Virtual Machine Platform-independent software implementation of a CPU that runs compiled code Virtualized representation of a physical machine run and maintained by virtualization software Behaves as though it is running on a stand-alone physical computer system 9
OS Virtualization Definitions Host Operating System Operating system actually running on the host machine hardware Guest Operating System Operating system running in the simulated environment / virtual machine 10
OS Virtualization Definitions Virtual Disk or Virtual Hard Drive A virtual machine s file-based physical representation of a hard drive, either in the form of a single file, as in Hyper-V, or a collection of related files, as in VMware products Appears to the virtual machine as a physical hard disk In some instances VM s can also use real hard drives, drive partitions or logical volumes 11
OS Virtualization Definitions Virtual Machine Monitor (VMM) Software that runs virtual machines in conjunction with the host operating system Provides the illusion of a real machine to one or more VMs Virtualizes some hardware (typically processor, memory, hard disk) Creates emulated devices or connects/ bridges to actual devices for VMs running on the host machine 12
OS Virtualization Definitions Hypervisor Special VMM running directly on hardware without no intervention from the host OS to provide access to hardware resources Note: Some sources call all Virtual Machine Monitors hypervisors regardless of their relationship with the OS Examples: VMWare ESX Server, Windows Hyper-V Server 2008, Citrix XenServer 13
Disaster Recovery Most enterprises are inadequately prepared for disaster striking their IT systems 40% of businesses experiencing a disaster never recover! Disaster recovery strategies are always desirable but are often unfundable All to often nothing is done 14
What Is Your Cost of Downtime? Productivity Number of employees impacted X hours out X burdened hourly rate Damaged Reputation Customers Suppliers Financial markets Banks Business partners... Source: Gartner Research Know your downtime costs per hour, day, two days... Other Expenses Temporary employees, equipment rental, overtime costs, extra shipping costs, travel expenses... Revenue Direct loss Compensatory payments Lost future revenue Billing losses Investment losses Financial Performance Revenue recognition Cash flow Lost discounts (A/P) Payment guarantees Credit rating Stock price 15
Disaster Recovery Methods Tape backup Unwieldy and slow Requires access to the same hardware Notorious for failing when actually needed Disk-to-disk Increasingly popular and simpler than tape Still requires the same hardware for use Both require physical removal 16
Disaster Recovery Methods Electronic vaulting Batch transfer of data to an off-site facility Remote journaling Transfer of live transactions to an off-site facility Database shadowing Storage of duplicate online transaction data, along with databases, at a remote site with a redundant server Data Replication Complete replication of all data off-site 17
Disaster Recovery Best Method Data Replication off-site In large organizations only the most mission-critical resources are replicated In small to medium businesses it s virtually (pun intended) unheard of The big problem: replication systems must be identical Costs many $$$$! 18
Replication for Disaster Recovery Backup and restoration to another system may seem simple, but sensitivity of many critical applications to hardware makes it a serious challenge Costs of identical systems for replication are prohibitive for all but the largest organizations 19
Virtualization and Replication Since virtual machines abstract the OS and even storage from the hardware, they eliminate the need for identical systems And since a virtual machine is just a file on a hard drive, replication of the entire system including OS as well as data becomes relatively simple 20
Virtualization and Replication Operating system virtualization is often coupled with another type of virtualization: storage virtualization Storage virtualization abstracts storage from the drives where data is physically located In wide use as RAID, Network Attached Storage (NAS) and Storage Area Networks (SAN) 21
Virtualization and Replication Many enterprise-level virtualization products require external storage for virtual hard drives (VHDs) VMware requires a SAN or iscsi Separating the VHD from the physical server entirely makes replication even easier 22
Impact of Virtualization Servers: consolidate services onto the fewest number of physical machines Balance load Increase server efficiency Reduce cost Improve survivability http://www.vmware.com/img/serverconsolidation.jpg 23
Virtualization and Replication By replicating the VHD to a remote site, we improve recovery point objective (RPO) Since recovery is almost instantaneous, we improve recovery time objective (RTO) System can be tested at the remote site with no impact on the primary site Remote site can run the VM on any hardware meeting minimum requirements May impact responsiveness but the system still runs! 24
Virtualization and Replication According to VMware, more than 55% of enterprises moving to server virtualization do so for the disaster recovery benefits Server virtualization can bring this benefit even to very small organizations Especially since enterprise-level solutions are available for free 25
Virtualization in the OS Virtualization becoming part of all server OS & hardware implementations Microsoft: Hyper-V in Server 2008 Red Hat: moving to KVM (kernel-based virtual machine) hypervisor and now has Xen Microsoft and Red Hat signed an agreement to crosssupport each others OSes as virtual machines Novell SUSE Linux includes Xen virtualization Oracle and Sun both offer virtualization platforms Both AMD and Intel provide hardware-level virtualization support in current chipsets 26
Free Virtualization Implementations Citrix XenServer VMware ESXi Microsoft Hyper-V Server 2008 Oracle VM Sun xvm 27
Planning for Virtual Replication Virtualization facilitates replication but is NOT automatic or even very easy Only rudimentary replication can be achieved with free tools; full enterprise-level implementation requires commercial versions $1,500-$5,700 per server 28
Planning for Virtual Replication Decide what to replicate Decide where you will replicate to Ensure critical business functions Should be based on a Business Impact Analysis (BIA) May also facilitate compliance with regulatory requirements like the Sarbanes-Oxley Act and the Health Insurance Portability and Accountability Act (HIPPA) 29
Our Data Replication Plan IIT s Center for Professional Development is developing a virtualization-facilitated data replication plan for academic support servers Using VMware and XenServer Replicate from IIT Rice Campus to IIT Main Campus and vice-versa 30
Our Data Replication Plan CPD Servers Main Campus Rice Campus VHDs Rice Campus SAN 100 Mbps WAN Link CPD Servers Rice Campus Main Campus SAN Main Campus VHDs 31
Learn More IIT s Information Technology & Management Degree Programs offers: ITM 454 Operating System Virtualization ITM 588 Incident Response, Disaster Recover and Business Continuity (I teach them both!) 32
The End Questions? 33