Deploying Application and OS Virtualization Technologies Together: Citrix and Virtuozzo

White Paper
Deploying Application and OS Virtualization
Together: Citrix and Virtuozzo
www.swsoft.com
Version 1.0Table of Contents
The Virtualization Continuum: Deploying Virtualization Together ...................................................... 3 -Virtualization Technologies ....................................................................................................... 3 -Hardware Virtualization ...................................................................................................... 3 -Paravirtualization ............................................................................................................... 3 -OS Virtualization ................................................................................................................ 4 -Application Virtualization .................................................................................................... 4 -Why Virtuozzo and Citrix? ........................................................................................................ 5 -Single Server Multiple Citrix Applications ................................................................................. 5 -Consolidation Benefits ...................................................................................................... 6 -Management Benefits ....................................................................................................... 6 -Unique Virtuozzo Benefits ................................................................................................. 6 -Virtuozzo and Citrix Best Practices .......................................................................................... 7
© SWsoft Deploying Application and OS Virtualization Together: Citrix and Virtuozzo The Virtualization Continuum: Deploying Virtualization Together
There are a variety of virtualization technologies available and the lines are becoming blurred between the different types. When is it appropriate to use one type of technology? Is it beneficial to use multiple types of virtualization technologies together? As virtualization becomes more pervasive in the datacenter, organizations are deploying multiple technologies. A significant trend is using complementary types of virtualization technologies together to provide an even stronger and more robust solution and ROI for the IT organization.
This whitepaper defines the different types of virtualization and explores the relationship and potential benefits of blending two types of virtualization, in particular: application and OS virtualization using Citrix and Virtuozzo.VIRTUALIZATION TECHNOLOGIESWhile this is not an exhaustive list, arguably, the most important types of virtualization being deployed today are: hardware virtualization, para-virtualization, OS virtualization and application virtualization.Hardware VirtualizationHardware Virtualization, Virtual Machine Monitor or Hypervisor are different names for essentially the same technology. The most common examples of hardware virtualization are VMware,Microsoft Virtual Server and Parallels. This technology is known as hardware virtualization because VMM/Hypervisoreverything from the hardware up is virtualized. The diagram in figure one VM 1 VM 2 VM 3shows the hardware virtualization Guest OS Guest OS Guest OStechnology. Building from the server up, you see they hypervisor layer (which is a modified Linux kernel) Virtual Hardware Virtual Hardware Virtual Hardwareand then the VMM layer. The virtual Virtual Machine Monitormachine monitor virtualizes every piece of hardware on the server, from Hypervisor or Standard Host OS CPU to memory to video cards. In Hardwarethe virtual machine, there is a guest OS, and finally the application or workload. Figure 1: Hardware Virtualization
Hardware virtualization is powerful because it enables any operating system to run side by side on the same server. The flexibility of this architecture comes with some drawbacks, it has duplicate layers of processing: two layers of OS ( the hypervisor and the Guest OS). It also has two layers of hardware: the real hardware and the virtual hardware. These duplicate layers add additional processing and make it difficult to run production high I/O applications. Another drawback is manageability. With hardware virtualization, you're actually increasing the number of OSs that you manage. In the pi... [download for more]