What is virtualization

Transcription

1 Virtualization Concepts

2 Virtualization Virtualization is the process of presenting computing resources in ways that users and applications can easily get value out of them, rather than presenting them in a way dictated by their implementation, geographic location, or physical packaging. In other words, it provides a logical rather than physical view of data, computing power, storage capacity, and other resources. Jonathan Eunice, Illuminata Inc

3 Objectives After completing this topic, you should be able to: Describe what is virtualization Know the advantages of Virtualization Describe the different types of Virtualization

4 What is virtualization The creation of many virtual resources from one physical resource. The creation of one virtual resource from one or more physical resource.

5 Virtualization in the News Microsoft acquired Connectix Corporation, a provider of virtualization software for Windows and Mac based computing, in early Late 2003, EMC announced its plans to acquire VMware for $635 million. VERITAS announced that it was acquiring an application virtualization company called Ejascent for $59 million. Sun and Hewlett-Packard have been working hard in recent times to improve their virtualization technologies.

6 Advantages of Virtualization Consolidation to reduce hardware cost. Optimization of workloads. Increased IT flexibility and responsiveness. Create an on demand, secure, and flexible infrastructure. Virtual machines can be used to provide secure, isolated sandboxes for running untrusted applications. E.g. JVM

7 Types of Virtualization Server Virtualization Desktop / Application Virtualization Network Virtualization Storage Virtualization

8 Server Virtualization A thin low level software layer call Hypervisor Intercepts OS calls to hardware Provides virtualized CPU and memory for guests

9 Hypervisor 2 types of Hypervisors: Type 1 Type 2 Bare metal / Native Runs directly on the hardware with guest OS running on top of them E.g. LPAR Runs on top of existing OS with guest OS running as third level above the hardware E.g. VMware Workstation

10 Advantages of Server Virtualization Increased Hardware Utilization Security Clean images can be used to restore compromised systems. Virtual machines can also provide sandboxing Development Debugging and performance monitoring scenarios easily setup in a repeatable fashion. Developers have easy access to OS they might not be able to install on their desktops.

11 Disadvantages of Server Virtualization Security More entry points such as the hypervisor and virtual networking layer to monitor. Administration There are more machines in aggregate. Licensing/Cost Accounting Performance Virtualization effectively partitions resources such as RAM and CPU on a physical machine.

12 Application Virtualization Not installed in the traditional sense BUT executed traditionally Application publishing E.g. Citrix Presentation Server API virtualization/emulation Virtualize only portion of software E.g. WINE (Linux), WABI (SUN), Crossover (OsX)

13 Advantages of Application Virtualization Security Virtual applications run in user mode isolating them from OS level functions. Management Centrally managed software patches Legacy Support Legacy applications can be run on modern operating systems Access Virtual applications can be installed on demand to provide failover and replication.

14 Disadvantages of Application Virtualization Packaging Applications must first be packaged before they can be used. Resources Virtual applications may require more resources in terms of storage and CPU. Compatibility Not all applications can be virtualized easily.

15 Desktop Virtualization Able to host and centrally manage desktop virtual machines in the data center Able to give end users a full PC desktop experience. E.g. Vmware, Virtual PC, Virtual Box

16 Advantages of Desktop Virtualization High Availability Downtime can be minimized with replication and fault tolerant hosted configurations. Extended Refresh Cycles Extend lifespan of client PC. Multiple Desktops Users can access multiple desktops suited for various tasks from the same client PC.

17 Disadvantages of Desktop Virtualization Licensing/Cost Accounting Performance Virtualization effectively partitions resources such as RAM and CPU on a physical machine.

18 Network Virtualization Virtual LAN (VLAN) Virtual Private Networks (VPN)

19 Advantages of Network Virtualization Customization of Access Administrators can quickly customize access and network options such as bandwidth throttling and quality of service. Consolidation Physical networks can be combined into one virtual network for overall simplification of management.

20 Disadvantages of Network Virtualization Increased complexity Performance overhead Need for administrators to have a larger skill set.

21 Storage Virtualization RAID process of abstracting logical storage from physical storage

22 Advantages of Storage Virtualization Migration Data can be easily migrated between storage locations without interrupting live access to the virtual partitions. Utilization Utilization of storage devices can be balanced to address over and under utilitization. Management Many hosts can leverage storage on one centrally managed physical device.

23 Disadvantages of Storage Virtualization Lack of Standards and Interoperability Storage virtualization is a concept and not a standard. Metadata There is a mapping between logical and physical location, the storage metadata and its management becomes key to a working reliable system.

24 Which virtualization are we learning? IBM Virtualization: HMC LPAR Hardware Management Console Logical Partition Allows running multiple, independent Operating system images of AIX and Linux on a single server

25 Web links n/