Virtual Machine Overview

1. Virtual Machine Overview

2. Agenda • What is Virtual Machine ? • How can virtualization help us ? • Major Virtual Machine Techniques • Introducing 4 popular Virtual Machine • XEN • KVM • VirtualBOX • VMware player

3. What's Virtual Machine ? • Virtual machine (VM): A software implementation of a machine (computer) that executes programs like a physical machine. • Types of virtual machine categories: • System virtual machines - Hardware virtual machine Provides a complete system platform environment which supports the execution of a complete operating system (OS). • Process virtual machine - Application virtual machine Provides a platform-independent programming environment that abstracts away details of the underlying hardware or operating system from software or application runtime. • Example: • Hardware virtual machine: VMWare, Xen, VirtualBOX .. • Application virtual machine: Java Virtual Machine, .NET Framework (From Wikipedia)

4. How can virtualization help us ? • Test before we go: Virtual machine just like a experiment box. You are able to test your application on different kind of system in same machine. It's easy to destroy, rebuild or backup your whole testing environments - Virtual Machine. • Server consolidation: Many small physical servers could be replaced by virtual machine, runs on virtualization environment provided by one powerful physical server. Although hardware is consolidated, typically OSs are not. Instead, each OS running on a physical server becomes converted to a distinct OS running inside a virtual machine. The large server can "host" many such "guest" virtual machines. • Increase hardware utilization: To increase the utilization of costly hardware resources such as cpu, memory or even like storage space. • Rapid provisioning, dynamic fault tolerance.. For example: • Computing task can now be utilized down to core of cpu level. • Big system memory can partition as smaller portions for legacy system runs within a virtual machine.

5. Traditional vs. Virtual Architecture • ( Quote from VMware ) Traditional Architecture Virtual Architecture

6. Xen Architecture • ◇ Virtual machine layer • ◇ Hypervisor layer • ◇ Hardware/physical layer • Hardware or physical layer: • Physical hardware components including memory, CPU, network cards, and disk drives. • Hypervisor layer: • Thin layer of software that runs on top of the hardware. The Xen hypervisor gives each virtual machine a dedicated view of the hardware. • Virtual machine layer: • Operating system hosted on the hypervisor and appearing to the user as a separate physical computer. However, the machine shares physical resources with other virtual machines, and it is portable because the virtual machine is abstracted from the physical hardware.

7. VM Techniques (1) - Full-Virtualization • Technical aspects: Full virtualization is a virtualization technique used to provide a certain kind of virtual machine environment, saying, a complete simulation of the underlying hardware which represents total abstraction of the underlying physical system, and create a complete virtual system in which the guest operating system can execute. In such an environment, any software capable of execution on the raw hardware, can be run in the virtual machine and; in particular, any operating systems (Guest Operating System). No modification is required in the guest operating system or application; the guest operating system or application is not even aware that it is running within a virtualized environment. • Typical solution of Full-Virtualization: • Commercial: VMWare ESX, Microsoft Virtual Server, Citrix XenServer. • Opensource: Linux Xen hypervisor – Hardware Virtual Machine (HVM), KVM.

8. Full-Virtualization - Continue • Advantages: • Operating System does not need to be modified in order to run in a virtualized environment. • Virtual machine can smoothly, easily change to different virtual system. Example: converting VMWare guest image into Xen image • Disadvantages: • Incur performance and resource penalty on VMs. • Some Virtual Machine require CPUs with special virtualization support built in (such as Intel-VT and AMD-V), Example: Xen.

9. VM Techniques (2) - Para-Virtualization • Technical aspects: Para-virtualization is a virtualization technique that attempts to provide most services directly from the underlying hardware instead of abstracting it. Para-virtualization allows for near-native performance. Para-virtualization requires that a guest operating system be modified to support virtualization. This typically means that guest operating systems are limited to open source systems such as Linux. • Typical solution of Para-Virtualization: • Commercial: Sun Solaris container. • Opensource: Linux Xen Hypervisor.

10. Para-Virtualization - Continue • Advantages: • Para-virtualized guest system comes closer to native performance than a fully virtualized guest. • The latest virtualization CPU support is not needed for para-virtualized. • Disadvantages: • Requires that a guest operating system be modified to support virtualization. This typically means that guest operating systems are limited to open source systems such as Linux. • It is not possible to migrate a guest Operating System from one platform to another.

11. VM Techniques (3) - Hardware assisted Full-Virtualization • Hardware-assisted virtualization: • Is a platform virtualization approach that enables efficient full virtualization using help from hardware capabilities, primarily from the host processors. • Hardware-assisted virtualization was recently (2006) added to x86 processors (Intel VT or AMD-V). • Is also known as accelerated virtualization; Xen calls it hardware virtual machine (HVM). KVM--which stands for "Kernel-based Virtual Machine"--provides for hardware-assisted virtualization.

12. VM Techniques (3) - Hardware assisted Full-Virtualization - Continue • Benefits of Hardware-Assisted Virtualization: • Hardware-assisted virtualization changes the access to the operating system itself. • With hardware-assisted virtualization, the operating system has direct access to resources without requirement to any emulation or OS modification.

13. Introducing 4 popular Virtual Machine Software • XEN • KVM • VirtualBOX • VMware player

14. XEN (1) • Xen is a virtual machine monitor for IA-32 (x86, x86-64), IA-64 and PowerPC 970 architectures. It allows several guest operating systems to be executed on the same computer hardware concurrently. • Xen was initially created by the University of Cambridge, Computer Laboratory and is now developed and maintained by the Xen community as free software, as well as Citrix XenServer Commercial version variant. • A Xen system is structured with the Xen hypervisor as the lowest and most privileged layer. Above this layer are “one” or “more” guest operating systems, which the hypervisor schedules across the physical CPUs. • The first guest operating system called in Xen terminology a.k.a "domain 0" (dom0), is booted automatically when the hypervisor boots and given special management privileges and direct access to the physical hardware. • System administrator can log into dom0 in order to manage any further guest operating systems, called "domain U" (domU) in Xen terminology.

15. XEN (2) $ xm list Name ID Mem(MiB) VCPUs State Time(s) CentOS5.3_testbed 79 2047 2 -b---- 7039.6 Ubuntu9.10_testbed 14 2047 1 -b---- 114443.9 Domain-0 0 25456 8 r----- 8021232.4

16. KVM (1) KVM (for Kernel-based Virtual Machine) • Open source software, full virtualization solution for Linux on x86 hardware, which containing virtualization extensions (Intel VT or AMD-V). It consists of a loadable kernel module: • “kvm.ko”, that provides the core virtualization infrastructure. • “kvm-intel.ko”, processor specific module for Intel CPU. • “kvm-amd.ko”, processor specific module for amd CPU. KVM also requires a modified QEMU although work is underway to get the required changes upstream. • By using KVM, one can run multiple virtual machines running unmodified Linux or Windows images. Each virtual machine has private virtualized hardware: a network card, disk, graphics adapter, etc. • The kernel component of KVM is included in mainline Linux, as of 2.6.20.

17. KVM (2) KVM Architecture – with Linux Kernel modules `

18. VirtualBox (1) VirtualBox is a powerful x86 and AMD64/Intel64 virtualization product for enterprise as well as home use. Not only is VirtualBox an extremely feature rich, high performance product for enterprise customers, it is also the only professional solution that is freely available as Open Source Software under the terms of the GNU General Public License (GPL). Presently, VirtualBox runs on Windows, Linux, Macintosh and OpenSolaris hosts and supports a large number of guest operating systems including but not limited to Windows (NT 4.0, 2000, XP, Server 2003, Vista, Windows 7), DOS/Windows 3.x, Linux (2.4 and 2.6), Solaris and OpenSolaris, and OpenBSD. Nice user interface and easy to install on Windows or Linux. Free Download : http://www.virtualbox.org/wiki/Downloads

19. VirtualBox (2) Screenshot of Windows VM running on Linux’s system via VirtualBox

20. VMware player (1) VMWare, Inc. Commercial software provider, specialize for providing virtualization software and corresponding solution. VMware has many popular virtualization solution across windows and linux platform, like: VMware Workstation, Server, ESX, GSX and client side software called VMWare player. VMware Player provide a easiest way to run multiple operating systems at the same time on your desktop. With its user-friendly interface, VMware Player makes it effortless for anyone to try out Windows 7, Chrome OS or the latest Linux releases, or create isolated virtual machines to safely test new software and surf the Web. VMware Player can also be used to run a virtual copy of an old PC so that you can recycle the old machines you have under your desk or stored in the closet. Download: http://www.vmware.com/go/downloadplayer/

21. VMware player (2) Screenshot of Linux VM running on Windows’ system via VMWare player

22. How Infrastructure as a Service (IaaS) utilize Virtualization • From WikipediA: • Cloud infrastructure services or "Infrastructure as a Service (IaaS)" delivers computer infrastructure, typically a platform virtualization environment as a service. • Company provide IaaS – Clouds vendors: • Amazon's EC2 (Elastic Compute Cloud) • Google's App Engine • Microsoft's Azure platform • TCloud Computing - Elaster All the vendors above provide services for delivering custom’s applications to internet environment and still maintain flexibility, configurability and pay-only-for-what-you-use model to the client when subscribe their services. All cloud service provider leverage the virtualization technologies as a fundamental building block in the whole infrastructure and management stack.

23. Amazon’s Elastic Compute Cloud EC2 and Virtualization – Xen • Amazon Elastic Compute Cloud (EC2): • A central part of Amazon.com's cloud computing platform, EC2 allows users to rent virtual computers on which to run their own computer applications. • EC2 allows scalable deployment of applications by providing a web service the - Amazon Web Services (AWS) which a user can create a virtual machine, boot an Amazon Machine Image to which Amazon calls an "instance", containing any software desired. • EC2 uses Xen virtualization. Each virtual machine, called an "instance", functions as a virtual private server. • Private Clouds: A private cloud is a cloud computing infrastructure created by an organization for its own internal use, rather than using someone else’s infrastructure (e.g., Amazon EC2). Many opensource project provide management software as a virtualization framework management utility for private cloud.

24. Introduce two virtualization management software • OpenNebula is a virtualization control framework, an open-source toolkit to easily build any type of cloud, includes private, public and hybrid. • OpenNebula has been designed to be integrated with any networking and storage solution and so to fit into any existing data center, such as EC2 service. An Opennebulas architecture

25. Introduce two virtualization management software - Coutinue • Eucalyptus - Elastic Utility Computing Architecture for Linking Your Programs To Useful Systems“ • An infrastructure for the implementation of cloud computing on computer clusters which provides an interface that is compatible with the Amazon EC2 service. • With Eucalyptus, Users make more efficient use of their computing capacity, thus increasing productivity and innovation, deploying new applications faster, and protecting sensitive data while making savings in capital expenditure. • Reference: http://www.eucalyptus.com/

26. Hands on: • Build your own first virtualization • sandbox .. with VMWare Player • Introduction of VMWare Player • What is VMWare Player • Get your software for free • Installation and setup • Prepare your own VM images .. Windows, Linux, .. • VMWare software runs on different platforms: • MS Windows, Linux, Mac OSX.

27. Introduction of VMWare Player - What is VMWare Player • Freeware virtualization software • VMWare player is for personal non-commercial use of virtualization software released by EMC Corp. It can runs on Windows and Linux 32bits or 64 bits OS platform. • VMWare player main aim is on target to compare with same implementation of desktop virtualization product from Microsoft - Virtual PC, which is Microsoft's free desktop virtualization software. • Somethingwe have to know .. • The VMWare Player’s versions which is earlier than 3.0.0 were unable to create virtual machines, meaning users have to get pre-installed virtual machines, manually create and edit vm’s profile for VMWare Player. Version 3.0.0 or later lifts this limitation, allowing users to create new virtual machines in the GUI.

28. Introduction of VMWare Player - Get your software for free • Register you VMWare Player license and get the software: • Download and register VMWare Player, go to visit VMWare website, fill the form and get software download link from license notification email. • Http://www.vmware.com/products/player/

29. Introduction of VMWare Player - Installation and setup • Run VMWare installer • When finished download VMWare Player software, open the software installer. Software installation will use total 200MB around disk space for the last version 3.1. • After VMWare Player installation finished, open the “VMWare Player”, complete the license agreement. Then may start to configure the system environment: • In preferences, download VMWare Tools , The “VMware Tools” package provides supports required for shared folders and for drag and drop operations, and better display performance of VMs. • If need more advance features in VMWare solution, users are required to upgrade the Player to “VMWare Workstation.

30. Introduction of VMWare Player - Prepare your own VM images .. • Create virtual machine in VMWare Player • Acquire operating system iso image or make use of host machine’s dvd device directly. VMWare player will emulate pc bios, find out a bootable device which follows the boot device sequence setup in vm’s bios • User can create vm firstly, after vm(s) created, then configure boot device and media source for installation. Just like we will go for buying a bare metal box (PC), and get start to install operating system after complete to assemble pc with components like cpu(s), ram(s) and hard drive(s). • Select a “Guest Operating System (vm)”, and pick up correct version (distribution) for that media source you are using. Remember that VMWare Player can install both 32 or 64bits guest os on 64bits host (server), but can’t install 64bits vm on 32bits host (server).

31. Introduction of VMWare Player - Installation and setup, continue • Select “Version” (guest OS). for what operating system you are going to install. • Decide the location (local) for where vm’s virtual hard drive (HDD) and profile repository to store, the location supposedly to has a large space to store many vm’s “vmdk” – virtual machine disk file. • VM(s) can be migrated and backup via copy whole installation directory of the vm(s) to another server

32. Introduction of VMWare Player - Prepare your own VM • Configure vm host to store vm’s virtual disk(s) with single giant file or multiple one; file access performance of vm will be degraded if user create a single big file for vm. User are suggested to create separated multiple files if need big disk space for vm. • Refer to VM’s profile information listed here, more customization of hardware's specification can be adjusted via select “Customize Hardware …”: • Memory • Number of cpu(s) • DVD • Type of device controller: IDE or SCSI • Network adapter: Bridge, NAT, host only

33. Introduction of VMWare Player - Prepare your own VM, continue • Common Networking Configuration Explanation of VMWare: • Bridged Networking Bridged networking connects a virtual machine to a network by using the host computer’s network adapter. • Host-Only Networking Host-only networking creates a network that is contained within host machine itself; This approach can be useful to set up an isolated virtual network. In this configuration, the virtual machine cannot connect to the Internet. • Network Address Translation The virtual machine and the host share a single network identity that is not visible outside the network. NAT can be useful when your network administrator lets you use a single IP address or MAC address.

34. Introduction of VMWare Player - Prepare your own VM, continue • When finish the configuration of vm(s), select your vm from vm repository, edit “virtual machine settings …”: • Change the CD/DVD connection to use ISO image or physical drive of host machine. • Select Connect at power on (means “start vm”) • Right click to select “Play Virtual Machine“, after vm boot up, follow the OS installation processes to finish the new OS installation. Notice: there is message remind user toinstall “vmware tools”, but it can be doneafter os installation completed.

35. Introduction of VMWare Player - Prepare your own VM, continue • Install VMWare Tools in to VM(s): • Enable “Install VMWare Tools…”, and • open a console extract the vmware tools package from the vm’s cdrom. • Run the installation script “./vmware-install.pl”, wait for installation processes completed, then reboot the system again to let the changes take effect (change of the display driver can take place right away). • After vm system reboot , vm preparation is now completed

36. Screenshot of new vm - CentOS on windows..

37. Reference http://en.wikipedia.org/wiki/Virtual_machine http://www.xen.org/ http://www.linux-kvm.org/page/Main_Page http://www.virtualbox.org/ http://www.vmware.com/ http://www.eucalyptus.com/ http://opennebula.org/