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Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
Open source hypervisors in cloud
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Open source hypervisors in cloud

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Description of two open Source hypervisiors and their comparision

Description of two open Source hypervisiors and their comparision

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  1. Content listVirtualization IntroductionVirtualization approachesTypes of HypervisorsX86 architecture model- Ring and Virtualised modelParameters for computing efficiency of HypervisorOpen source hypervisor description- KVM and XenComparison between KVM and XenComparative Analysis of KVM with XenConclusionCons of KVM
  2. What is Virtualization? INTRODUCTIONVirtualization is making one computer appear to be multiple computers.Virtualization is accomplished with a program called a hypervisor, while systemsrunning under a hypervisor are known as virtual machines (VMs).
  3. Defining Virtualization ApproachesVirtualization can achieved by two types. These description of Hypervisor are based onhardware virtualizationa) Full Virtualization: Full virtualization uses the entire systems resources areabstracted by the virtualization software layer.Fully virtualized workloads do not require any change or modification to their guestoperating systems.Ex- Vmwareb) Para Virtualization: Para virtualization uses only a portion of the systemsresources, or partial amount, is abstracted by the virtualization software layer.Paravirtualization requires that the guest operating system running on the host server bemodified so that it recognizes the virtualization software layer.Ex- Initial version of Xen (Xen PV)
  4. Types of hypervisor:Type 1 HypervisorType 1 Hypervisors run directly on the hosts hardware to control the hardware and tomanage guest operating systems. A guest operating system thus runs on another levelabove the hypervisor.Examples of some popular Type 1 Hypervisors are VMwares ESX Server, Suns LogicalDomains Hypervisor and Xen etc. Type 2 Hypervisor TYPE1 Hypervisor Figure 1 Google Images
  5. Type 2 HypervisorHypervisors runs as a normal program inside a normal operating system. This OS isknown as the host. It run over 3nd level over hardware .Each guest OS runs as aprocess in the host Operating system. These processes can be manipulated just likeany other process. Examples of some popular Type 2 Hypervisors are VMwareserver, KVM, Virtualbox etc.Examples of some popular Type 2 Hypervisors are VMwareserver, KVM, Virtualbox, etc. Type2 Hypervisor Figure 2 Google Images
  6. X86 architecture Virtualization Model X86 architecture has been taken as reference which is powerful virtualizedcomputing architecture with more than eight processors and high speedCPU.X86 architecture is divided into rings; each ring has access to specific layerand privileges. User application has access lower layer ring 3. In general OSsystem has access to ring 0 and enjoy full privileged to access hardware. Andring 1 & 2 are generally not in use. So applications user cannot execute asystem call or instruction that is reserved by OS access while residing overring 3.
  7. X86 Architecture Model
  8. Virtualized X86 Architecture DescriptionIn case of virtualization VMs are placed at ring 1 or aboveallowed for a to access hardware call with binary translation inwhich the privileged instructions were trapped by a softwareinterpreter layer known as the Virtual Machine Monitor (VMM)or hypervisor, and converted to safe instructions that could bevirtualized. This technique allows the VMM to run in Ring 0 forisolation and performance, while moving the operating systemto a user level ring with greater privilege than applications was inRing 3 but less privilege than the virtual machine monitor on aRing 0.
  9. Virtualized X86 Architecture Model
  10. There are various parameters through which efficiency of hypervisors are judged such as(a) Scheduling Policy: It is based stability, security and robustness. Aggregate measure ofCPU, memory, network and disk IO for a given virtual machine.(b) Performance: It is judged on the bases of improving efficiency and Quality of service (QOS).(c) Memory: It allows maximum requirement of memory resources allocated to the system torun both guest and host.(d) Security: Must be empowered by high security policy as hypervisor is undoubtedly atempting target for hackers.(e) Cost: Maintaining large enterprise data on low cost.(f) Easy to Use: Hypervisors design and control must not be too complex to handle byadministrators.(g) Management: Managing with complexity must easier to accelerate in agility of businessworld.(h) Recovery: Proper backup and recovery mechanisms provided by software would bebeneficial for application and data
  11. Description of Open source HypervisorsKVM Hypervisor•KVM is a type-2 hypervisor, maintained by Qumranet Red Hat Corporation. It isbased on the QEMU emulator and derives all its management tools from QEMU.•KVM is a unique hypervisor. New versions from KVM-62 also have support forpar virtualized Linux guests, but did not utilize this capability in initial prototype.• The main focus of KVM development is to use the x86 VT extensions, whichallow virtual machines to make system calls.• KVM uses a set of Linux kernel as a module and will ship with any Linuxdistribution moving forward as no work is required for the Linux distributions toadd KVM.
  12. •KVM supports the QEMU Copy-on-write (QCOW) disk image format, allowing it tosupport a snapshot mode for its disk I/O operations.• Multiple VMs can be run from one disk image, somewhat mitigating the huge storagerequirements associated with hosting a grid of VM’s.•KVM supports the standard Linux TUN/TAP model for Ethernet bridging.•By using this model, each VM gets its own networking resources, making itindistinguishable from a physical machine.
  13. KVM Virtualization
  14. Xen Hypervisor•Xen is a type-1 hypervisor, maintained Xen.org community built independent ofany operating system•It is a complete separate layer from the operating system and hardware and isseen by the community and customers as an Infrastructure Virtualization Platformto build their solutions upon.•In fact, community is not in the business of building a complete solution, butrather a platform for companies and users to leverage for their virtualization andcloud solutions.•Xen hypervisor is found in many unique solutions today from standard servervirtualization to cloud providers to grid computing platforms to networkingdevices, etc.•Xen hypervisor is inserted between the servers hardware and the operatingsystem. This provides an abstraction layer that allows each physical server to runone or more "virtual servers", effectively decoupling the operating system and itsapplications from the underlying physical server
  15. •Xen is an open source virtual machine monitor for x86-compatible computers.•Xen makes it possible for multiple guest operating systems to run on a single computer by using a softwarelayer called a hypervisor to mediate access to the real hardware.In order to create a secure operating environment, Xen hypervisor divides the VMs into two domains i.e.Domain0 (Dom0) and Domain (DomU) due to the accessibility privileges.The Dom0 VMs have the higher privileges and they can access the hardware whereas DomU VMs have lowerprivileges and cannot directly access the hardware•Red Hat Inc. includes the Xen hypervisor as part of Red Hat Enterprise Linux (RHEL) software, describing thiscombination as "integrated virtualization."•Sun Microsystems provides support for Xen virtualization on Solaris 10, its version of the Unix operatingsystem. Other mainstream Linux distributions, including Debian and SuSE, have thenecessary kernel extensions available to serve as the base OS for Xen.•Xen, which was released under the GNU General Public License, was originally a research project at theUniversity of Cambridge. Xen Source, Inc., a company that supported the development of the open sourceproject and enterprise applications of the software, was acquired by Citrix Systems in October 2007
  16. Xen Virtualization
  17. Comparison between KVM and Xen•KVM is a hypervisor that is based on Linux kernel. It has inherited MemoryManagement, Scheduling policy and Security from Linux Kernel. Whereas Xen is a hypervisorthat is based on Ubuntu, derived from Linux system has also in cooperating these three keyfeatures into its OS itself.•For example KVM Hypervisor are supported by Red Hat, AMD, HP, IBM, Novell, SGI and othersWhereas Xen hypervisors are currently used byCisco, Critix, Fujitsu, Lenovo, Novell, Oracle, Samsung, and various cloud providersAmazon, Cloud.com, Go Grid and Rackspace.•KVM is part of Linux and uses the regular Linux scheduler and memory management. Thismeans that KVM is much smaller and simpler to use. On the other hand ,Xen is an externalhypervisor; it assumes control of the machine and divides resources among guests.,KVM runs on processors that support hvm, whereas Xen runs non-hvm compatible processors.KVM is easy to use and provide more features, whereas Xen is powerful but it requires goodamount of knowledge to operate.
  18. KVM need hardware assisted virtualization support (Intel VT-x, AMD AMD-V), whereas XenPV does not but cant run operating systems without PV support (you cant run Windows onXen PV).KVM will use parts of the Qemu virtualization software to emulate actual hardware fordevices not using PV drivers in the guest system.KVM is an internal part of the linux kernel module and uses regular memory and schedulerlike linux, whereas Xen is an external hypervisor that takes the control and divides theresources between the guest machinesKVM doesnt have any support for paravirtualization, whereas Xen supportsparavirtualization that is used for device drivers to improve the performance of input/output.•Xen has a mature and proven memory manager including support for NUMA and large scalesystems, whereas Xen hypervisor has needed to build this support from scratch
  19. KVM Hypervisor analysisOut of the two hypervisors KVM is best option to select among two. An analysis is conductedwhile keeping various points in the mindSecurity KVM follows Standard Linux security features SELinux (Security Enhanced Linux)project, developed by the US National Security Agency. It has sVirt projects builds on SELinuxInfrastructure that provides a level of security and isolation unmatched in industry.Memory Management NUMA supported by KVM allows virtual machines to efficiently accesslarge amounts of memory. KVM inherits the powerful memory management features of Linux.Memory page sharing is supported through a kernel feature called Kernel Same-pageMerging(KSM).Hardware support Since KVM is a part of Linux it leverages all types of hardware support ofLinux hardwares. Any new features are added to the Linux kernel are inherited to KVM
  20. Live Migration KVM supports live Migration which provides the ability to move a running virtualmachine between physical hosts with no interruption to service. Saving a virtual machinescurrent state to disk to allow it to be stored and resumed at a later time.Storage KVM is able to use any storage supported by Linux to store virtual machineimages, including local disks with IDE, SCSI and SATA, Network Attached Storage (NAS) includingNFS and SAMBA/CIFS or SAN with support for iSCSI and fiber Channel. Including all those featurewhich supported by any Linux storage device.Guest Support KVM supports a wide variety of guest operating systems, from mainstreamoperating systems such as Linux and Windows to other platforms includingOpenBSD, FreeBSD, OpenSolaris, Solaris x86 and MS DOS.Device Drivers KVM hypervisor supports the uses of VirtIO standard developed by IBM and RedHat in conjunction with the Linux community for paravirtualized for better guest interoperability.
  21. Performance and Scalability KVM inherits the performance and scalability of Linux, supportingvirtual machines with up to 16 virtual CPUs and 256GB of ram and host systems with 256 coresand over 1TB or RAM.Increased Response time In KVM, time elapses between a stimulus and the response isdecreased. Under this operating model, kernel processes that require a long CPU time slice aredivided into smaller components and scheduled/processed accordingly by the kernel.Improved scheduling and resource control In the KVM model, a virtual machine (is scheduledand managed by the standard Linux kernel. Kernel level is responsible for scheduling processesthat divides long CPU Scheduled time into slice of smaller components . So any request fromvirtual machines can be processed faster, thereby significantly reducing application processinglatency and improving determinism.
  22. ConclusionFor IT staff interested in zero-cost, Linux-friendly, feature-rich and resource-efficientvirtualization, KVM has become the way to go.The rapid maturation of KVM (Kernel-based virtual machine) over the course of the last coupleof years constituted the first open-source challenge. Integrated into the Linux kernel, KVMprovides feature-rich and highly efficient virtualization as things in virtualization land movepretty fast.As Boon for Small Vendors while glance over challenges of cloud computing for small vendorsin low hardware cost, KVM virtualization Service Provider (VSP) can sell compute power withouthaving to directly maintain each end-user’s particular application.Virtual Organizations (VOs) can purchase compute power from VSPs without having to worryabout hardware or software compatibility. A VO is free to develop a model clusterlocally, perhaps even on a personal workstation, test it, and then deploy it to a VSPs hardwarewith reasonable assurances that the operating environment will be fully compatible.
  23. Some Cons:Perhaps the single major downside of KVM is that it requires a bitmore technical know-how since some features can only beconfigured via manual hacking of XML files.KVM and related tools continue to mature, expect that to change.
  24. Thank you 
  25. What is Virtualization? INTRODUCTIONVirtualization is making one computer appear to be multiple computers.Virtualization is accomplished with a program called a hypervisor, while systemsrunning under a hypervisor are known as virtual machines (VMs).
  26. Defining Virtualization ApproachesVirtualization can achieved by either Full or Para Virtualization techniqueFull Virtualization: Full virtualization uses the entire systems resources are abstractedby the virtualization software layer.Fully virtualized workloads do not require any change or modification to their guestoperating systems.Ex- VmwarePara Virtualization: Paravirtualization uses only a portion of the systems resources, orpartial amount, is abstracted by the virtualization software layer.Paravirtualization requires that the guest operating system running on the host serverbe modified so that it recognizes the virtualization software layer.Ex- Initial version of Xen (Xen PV)Hypervisor descriptions are given here which are based on hardware virtualization
  27. Types of hypervisor:Type 1 HypervisorType 1 Hypervisors run directly on the hosts hardware to control the hardware and tomanage guest operating systems. A guest operating system thus runs on another levelabove the hypervisor.Examples of some popular Type 1 Hypervisors are VMwares ESX Server, Suns LogicalDomains Hypervisor and Xen etc. Type 2 Hypervisor TYPE1 Hypervisor Figure 1 Google Images
  28. Type 2 HypervisorHypervisors runs as a normal program inside a normal operating system. This OS isknown as the host. It run over 3nd level over hardware .Each guest OS runs as aprocess in the host Operating system. These processes can be manipulated just likeany other process. Examples of some popular Type 2 Hypervisors are VMwareserver, KVM, Virtualbox etc.Examples of some popular Type 2 Hypervisors are VMwareserver, KVM, Virtualbox, etc. Type2 Hypervisor Figure 2 Google Images
  29. X86 architecture Virtualization Model X86 architecture has been taken as reference which is powerful virtualizedcomputing architecture with more than eight processors and high speedCPU.X86 architecture is divided into rings; each ring has access to specific layerand privileges. User application has access lower layer ring 3. In general OSsystem has access to ring 0 and enjoy full privileged to access hardware. Andring 1 & 2 are generally not in use. So applications user cannot execute asystem call or instruction that is reserved by OS access while residing overring 3.
  30. X86 Architecture Model
  31. Virtualized X86 Architecture DescriptionIn case of virtualization VMs are placed at ring 1 or above allowed for a to accesshardware call with binary translation in which the privileged instructions weretrapped by a software interpreter layer known as the Virtual Machine Monitor (VMM)or hypervisor, and converted to safe instructions that could be virtualized. Thistechnique allows the VMM to run in Ring 0 for isolation and performance, whilemoving the operating system to a user level ring with greater privilege thanapplications was in Ring 3 but less privilege than the virtual machine monitor in Ring 0.
  32. Virtualized X86 Architecture Model
  33. There are various parameters through which efficiency of hypervisors are judged such as(a) Scheduling Policy: It is based stability, security and robustness. Aggregate measure ofCPU, memory, network and disk IO for a given virtual machine.(b) Performance: It is judged on the bases of improving efficiency and Quality of service (QOS).(c) Memory: It allows maximum requirement of memory resources allocated to the system to run bothguest and host.(d) Security: Must be empowered by high security policy as hypervisor is undoubtedly a tempting target forhackers.(e) Cost: Maintaining large enterprise data on low cost.(f) Easy to Use: Hypervisors design and control must not be too complex to handle by administrators.(g) Management: Managing with complexity must easier to accelerate in agility of business world.(h) Recovery: Proper backup and recovery mechanisms provided by software would be beneficial forapplication and data
  34. Description of HypervisorsKVM Hypervisor•KVM is a type-2 hypervisor, maintained by Qumranet Red Hat Corporation. It is based onthe QEMU emulator and derives all its management tools from QEMU.•KVM is a unique hypervisor. New versions from KVM-62 also have support for parvirtualized Linux guests, but did not utilize this capability in initial prototype.• The main focus of KVM development is to use the x86 VT extensions, which allow virtualmachines to make system calls.• KVM uses a set of Linux kernel as a module and will ship with any Linux distributionmoving forward as no work is required for the Linux distributions to add KVM.
  35. •KVM supports the QEMU Copy-on-write (QCOW) disk image format, allowing it tosupport a snapshot mode for its disk I/O operations.• Multiple VMs can be run from one disk image, somewhat mitigating the huge storagerequirements associated with hosting a grid of VM’s.•KVM supports the standard Linux TUN/TAP model for Ethernet bridging.•By using this model, each VM gets its own networking resources, making itindistinguishable from a physical machine.
  36. KVM Virtualization
  37. Xen Hypervisor•Xen is a type-1 hypervisor, maintained Xen.org community built independent ofany operating system•It is a complete separate layer from the operating system and hardware and isseen by the community and customers as an Infrastructure Virtualization Platformto build their solutions upon.•In fact, community is not in the business of building a complete solution, butrather a platform for companies and users to leverage for their virtualization andcloud solutions.•Xen hypervisor is found in many unique solutions today from standard servervirtualization to cloud providers to grid computing platforms to networkingdevices, etc.•Xen hypervisor is inserted between the servers hardware and the operatingsystem. This provides an abstraction layer that allows each physical server to runone or more "virtual servers", effectively decoupling the operating system and itsapplications from the underlying physical server
  38. •Xen is an open source virtual machine monitor for x86-compatible computers.•Xen makes it possible for multiple guest operating systems to run on a single computer by using a softwarelayer called a hypervisor to mediate access to the real hardware.In order to create a secure operating environment, Xen hypervisor divides the VMs into two domains i.e.Domain0 (Dom0) and Domain (DomU) due to the accessibility privileges.The Dom0 VMs have the higher privileges and they can access the hardware whereas DomU VMs have lowerprivileges and cannot directly access the hardware•Red Hat Inc. includes the Xen hypervisor as part of Red Hat Enterprise Linux (RHEL) software, describing thiscombination as "integrated virtualization."•Sun Microsystems provides support for Xen virtualization on Solaris 10, its version of the Unix operatingsystem. Other mainstream Linux distributions, including Debian and SuSE, have thenecessary kernel extensions available to serve as the base OS for Xen.•Xen, which was released under the GNU General Public License, was originally a research project at theUniversity of Cambridge. Xen Source, Inc., a company that supported the development of the open sourceproject and enterprise applications of the software, was acquired by Citrix Systems in October 2007
  39. Xen Virtualization
  40. Comparison between KVM and Xen•KVM is a hypervisor that is based on Linux kernel. It has inherited MemoryManagement, Scheduling policy and Security from Linux Kernel. Whereas Xen is a hypervisorthat is based on Ubuntu, derived from Linux system has also in cooperating these three keyfeatures into its OS itself.•For example KVM Hypervisor are supported by Red Hat, AMD, HP, IBM, Novell, SGI and othersWhereas Xen hypervisors are currently used byCisco, Critix, Fujitsu, Lenovo, Novell, Oracle, Samsung, and various cloud providersAmazon, Cloud.com, Go Grid and Rackspace.•KVM is part of Linux and uses the regular Linux scheduler and memory management. Thismeans that KVM is much smaller and simpler to use. On the other hand ,Xen is an externalhypervisor; it assumes control of the machine and divides resources among guests.,KVM runs on processors that support hvm, whereas Xen runs non-hvm compatible processors.KVM is easy to use and provide more features, whereas Xen is powerful but it requires goodamount of knowledge to operate.
  41. KVM need hardware assisted virtualization support (Intel VT-x, AMD AMD-V), whereas XenPV does not but cant run operating systems without PV support (you cant run Windows onXen PV).KVM will use parts of the Qemu virtualization software to emulate actual hardware fordevices not using PV drivers in the guest system.KVM is an internal part of the linux kernel module and uses regular memory and schedulerlike linux, whereas Xen is an external hypervisor that takes the control and divides theresources between the guest machinesKVM doesnt have any support for paravirtualization, whereas Xen supportsparavirtualization that is used for device drivers to improve the performance of input/output.•Xen has a mature and proven memory manager including support for NUMA and large scalesystems, whereas Xen hypervisor has needed to build this support from scratch
  42. KVM Hypervisor analysisOut of the two hypervisors KVM is best option to select among two. An analysis is conductedwhile keeping various points in the mindSecurity KVM follows Standard Linux security features SELinux (Security Enhanced Linux)project, developed by the US National Security Agency. It has sVirt projects builds on SELinuxInfrastructure that provides a level of security and isolation unmatched in industry.Memory Management NUMA supported by KVM allows virtual machines to efficiently accesslarge amounts of memory. KVM inherits the powerful memory management features of Linux.Memory page sharing is supported through a kernel feature called Kernel Same-pageMerging(KSM).Hardware support Since KVM is a part of Linux it leverages all types of hardware support ofLinux hardwares. Any new features are added to the Linux kernel are inherited to KVM
  43. Live Migration KVM supports live Migration which provides the ability to move a running virtualmachine between physical hosts with no interruption to service. Saving a virtual machinescurrent state to disk to allow it to be stored and resumed at a later time.Storage KVM is able to use any storage supported by Linux to store virtual machineimages, including local disks with IDE, SCSI and SATA, Network Attached Storage (NAS) includingNFS and SAMBA/CIFS or SAN with support for iSCSI and fiber Channel. Including all those featurewhich supported by any Linux storage device.Guest Support KVM supports a wide variety of guest operating systems, from mainstreamoperating systems such as Linux and Windows to other platforms includingOpenBSD, FreeBSD, OpenSolaris, Solaris x86 and MS DOS.Device Drivers KVM hypervisor supports the uses of VirtIO standard developed by IBM and RedHat in conjunction with the Linux community for paravirtualized for better guest interoperability.
  44. Performance and Scalability KVM inherits the performance and scalability of Linux, supportingvirtual machines with up to 16 virtual CPUs and 256GB of ram and host systems with 256 coresand over 1TB or RAM.Increased Response time In KVM, time elapses between a stimulus and the response isdecreased. Under this operating model, kernel processes that require a long CPU time slice aredivided into smaller components and scheduled/processed accordingly by the kernel.Improved scheduling and resource control In the KVM model, a virtual machine (is scheduledand managed by the standard Linux kernel. Kernel level is responsible for scheduling processesthat divides long CPU Scheduled time into slice of smaller components . So any request fromvirtual machines can be processed faster, thereby significantly reducing application processinglatency and improving determinism.
  45. ConclusionFor IT staff interested in zero-cost, Linux-friendly, feature-rich and resource-efficientvirtualization, KVM has become the way to go.The rapid maturation of KVM (Kernel-based virtual machine) over the course of the last coupleof years constituted the first open-source challenge. Integrated into the Linux kernel, KVMprovides feature-rich and highly efficient virtualization as things in virtualization land movepretty fast.As Boon for Small Vendors while glance over challenges of cloud computing for small vendorsin low hardware cost, KVM virtualization Service Provider (VSP) can sell compute power withouthaving to directly maintain each end-user’s particular application.Virtual Organizations (VOs) can purchase compute power from VSPs without having to worryabout hardware or software compatibility. A VO is free to develop a model clusterlocally, perhaps even on a personal workstation, test it, and then deploy it to a VSPs hardwarewith reasonable assurances that the operating environment will be fully compatible.
  46. Some Cons of KVM: Perhaps the single major downside of KVM is thatit requires a bit more technical know-how sincesome features can only be configured via manualhacking of XML files. KVM and related tools continue tomature, expect that to change.
  47. Thank you 

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