Documentation Virtualization Beat

Virtualization

Virtualization in Fedora 11 includes major changes, and new features, that continue to support KVM, Xen, and many other virtual machine platforms.

Improved VNC Authentication for Virtual Machine Management

Fedora 11 introduces the ability to use the SASL protocol for authenticating VNC connection to KVM and QEMU virtual machines. SASL is a pluggable system, allowing many different authentication mechanisms to be configured without changing the application code. The use of SASL, in combination with existing TLS encryption support, will allow clients like vinagre, virt-viewer and virt-manager to securely connect to remote virtual machine consoles hosted on Fedora servers. In environments where Kerberos is deployed, this further allows for secure single sign on to the VNC server. This new authentication capability obsoletes the traditional VNC password scheme which is not sufficiently secure.

For further details refer to the Virtualization VNC Authentication wiki page

Improved Graphical Console for Virtual Machines

Previous Fedora virtual guest consoles were limited to a screen resolution of 800x600, and the PS2 mouse pointer operated in relative coordinate mode. This prevented the guest pointer from tracking the local client pointer one for one.

Fedora 11 provides more accurate mouse pointer positioning and higher screen resolutions for virtual machine consoles. Fedora 11 guests default to a screen resolution of at least 1024x768, and are provided with a USB tablet in absolute coordinate mode. This results in a mouse pointer which tracks the local client pointer one for one.

For further details refer to the Improved Graphical Console for Virtual Guests wiki page

KVM PCI Device Assignment

Fedora 11 expands its virtualization capabilities to include KVM PCI device assignment support. KVM users can now give virtual machines exclusive access to physical PCI devices using Fedora's virtualization toools, including the Virtual Machine Manager application.

Hardware requirements
Intel VT-d or AMD IOMMU hardware platform support is required in order for this feature to be available.

For further details refer to the KVM PCI Device Assignment wiki page.

KVM and QEMU merge

QEMU provides a processor and system emulator which enables users to launch guest virtual machines of the same architecture as the host machine or of a dramatically different architecture. KVM provides kernel level support for running guests of the same architecture as the host.

QEMU takes advantage of KVM to run guests directly on the hardware without any translation needed by the host, allowing much higher levels of performance.

Fedora 11 includes a merge of the qemu and kvm RPMs. The kvm package is now obsoleted by the qemu-system-x86 subpackage of qemu. The merging of the two code bases continues upstream, but the Fedora package maintainers have chosen to merge the packages now in order reduce the maintenance burden and provide better support.

For further details refer to the KVM and QEMU merge wiki page

SVirt Mandatory Access Control

Fedora 11 integrates SELinux's Mandatory Access Control with Virtualization. Virtual machines can now be much more effectively isolated from the host and one another, giving the increased assurance that security flaws cannot be exploited by malicious guests.

For further details refer to the SVirt Mandatory Access Control wiki page.

Other Improvements

Fedora also includes the following virtualization improvements:

QEMU Updated to 0.10.0

QEMU is a generic and open source machine emulator and virtualizer.

When used as a machine emulator, QEMU can run OSes and programs made for one machine (e.g. an ARM board) on a different machine (e.g. your own PC). By using dynamic translation, it achieves very good performance.

When used as a virtualizer, QEMU achieves near native performance by executing the guest code directly on the host CPU. A host driver called the QEMU accelerator (also known as KQEMU) is needed in this case. The virtualizer mode requires that both the host and guest machine use x86 compatible processors.

New features and improvements since 0.9.1:

• TCG support - No longer requires GCC 3.x
• Kernel Virtual Machine acceleration support
• BSD userspace emulation
• Bluetooth emulation and host passthrough support
• GDB XML register description support
• Intel e1000 emulation
• HPET emulation
• VirtIO paravirtual device support
• Marvell 88w8618 / MusicPal emulation
• Nokia N-series tablet emulation / OMAP2 processor emulation
• PCI hotplug support
• Live migration and new save/restore formats
• Curses display support
• qemu-nbd utility to mount supported block formats
• Altivec support in PPC emulation and new firmware (OpenBIOS)
• Multiple VNC clients are now supported
• TLS encryption is now supported in VNC
• Many, many, bug fixes and new features

For further details refer to:

http://www.nongnu.org/qemu/about.html

KVM Updated to 84

KVM (for Kernel-based Virtual Machine) is a full virtualization solution for Linux on x86 hardware.

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.

New features and improvements since 74:

For further details refer to:

http://www.linux-kvm.org/page/ChangeLog

libvirt Updated to 0.6.1

The libvirt package provides an API and tools to interact with the virtualization capabilities of recent versions of Linux (and other OSes). The libvirt software is designed to be a common denominator among all virtualization technologies with support for the following:

• The Xen hypervisor on Linux and Solaris hosts.
• The QEMU emulator
• The KVM Linux hypervisor
• The LXC Linux container system
• The OpenVZ Linux container system
• Storage on IDE/SCSI/USB disks, FibreChannel, LVM, iSCSI, and NFS

New features and improvements since 0.4.6:

• new APIs for Node device detach reattach and reset
• sVirt mandatory access control support
• thread safety of the API and event handling
• allow QEmu domains to survive daemon restart
• extended logging capabilities
• support copy-on-write storage volumes
• support of storage cache control options for QEmu/KVM
• driver infrastructure and locking
• Test driver infrastructure
• parallelism in the daemon and associated config
• virsh help cleanups
• logrotate daemon logs
• more regression tests
• QEmu SDL graphics
• add --version flag to daemon
• memory consumption cleanup
• QEmu pid file and XML states for daemon restart
• gnulib updates
• PCI passthrough for KVM
• generic internal thread API
• RHEL-5 specific Xen configure option and code
• save domain state as string in status file
• add locking to all API entry points
• new ref counting APIs
• IP address for Xen bridges
• driver format for disk file types
• improve QEmu/KVM tun/tap performances
• enable floppies for Xen fully virt
• support VNC password settings for QEmu/KVM
• qemu driver version reporting

There were also dozens of cleanups, documentation enhancements, portability and bug fixes. For further details refer to: http://www.libvirt.org/news.html

virt-manager Updated to 0.7.0

The virt-manager package provides a GUI implementation of virtinst and libvirt functionality.

New features and improvements since 0.6.0:

• Redesigned 'New Virtual Machine' wizard
• Option to remove storage when deleting a virtual machine.
• File browser for libvirt storage pools and volumes, for use when attaching storage to a new or existing guest.
• Physical device assignment (PCI, USB) for existing virtual machines.
• VM disk and network stats reporting
• VM Migration support
• Support for adding sound devices to an existing VM
• Enumerate host devices attached to an existing VM
• Allow specifying a device model when adding a network device to an existing VM
• Combine the serial console view with the VM Details window
• Allow connection to multiple VM serial consoles
• Bug fixes and many minor improvements.

For further details refer to:

http://www.virt-manager.org/

virtinst Updated to 0.400.3

The python-virtinst package contains tools for installing and manipulating multiple VM guest image formats.

New features and improvements since 0.400.0:

• New virt-clone option --original-xml, allows cloning a guest from an xml file, rather than require an existing, defined guest.
• New virt-install option --import, allows creating a guest from an existing disk image, bypassing any OS install phase.
• New virt-install option --host-device, for connecting a physical host device to the guest.
• Allow specifying cache value via virt-install --disk options
• New virt-install option --nonetworks
• Add virt-image to vmx format support to virt-convert, replacing virt-pack
• Add disk checksum support to virt-image
• Enhanced URL install support: Debian Xen paravirt, Ubuntu kernel and boot.iso, Mandriva kernel, and Solaris Xen Paravirt
• Expanded test suite
• Numerous bug fixes, cleanups, and improvements

For further details refer to:

• http://www.virt-manager.org/

Xen Updated to 3.3.1

Fedora 11 supports booting as a domU guest, but will not function as a dom0 host until such support is provided in the upstream kernel. Support for a pv_ops dom0 is targeted for Xen 3.4.

Changes since 3.3.0:

• Xen 3.3.1 is a maintenance release in the 3.3 series.

For further details refer to:

• http://www.xen.org/download/roadmap.html -- Xen roadmap
• http://xenbits.xen.org/paravirt_ops/patches.hg/ -- paravirt_ops patch queue

Xen Kernel Support

The kernel package in Fedora 11 supports booting as a guest domU, but will not function as a dom0 until such support is provided upstream. Work is ongoing and hopes are high that support will be included in kernel 2.6.30 and Fedora 12.

The most recent Fedora release with dom0 support is Fedora 8.

Booting a Xen domU guest within a Fedora 11 host requires the KVM based xenner. Xenner runs the guest kernel and a small Xen emulator together as a KVM guest.

KVM requires hardware virtualization features in the host system.
Systems lacking hardware virtualization do not support Xen guests at this time.

For more information refer to:

• http://sourceforge.net/projects/kvm
• http://kraxel.fedorapeople.org/xenner/
• http://fedoraproject.org/wiki/Features/XenPvops
• http://fedoraproject.org/wiki/Features/XenPvopsDom0