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Virtualization

In this section, we cover discussion on the @et-mgmnt-tools-list, @fedora-xen-list, @libvirt-list and @ovirt-devel-list of Fedora virtualization technologies.

Contributing Writer: Dale Bewley

Enterprise Management Tools List

This section contains the discussion happening on the et-mgmt-tools list

New Release virt-manager 0.7.0

Cole Robinson announce[1] a new Package-x-generic-16.pngvirt-manager[2] release, version 0.7.0.

Virtual Machine Manager provides a graphical tool for administering virtual machines for KVM, Xen, and QEmu. Start, stop, add or remove virtual devices, connect to a graphical or serial console, and see resource usage statistics for existing VMs on local or remote machines. Uses Package-x-generic-16.pnglibvirt as the backend management API.

New features:

  • Redesigned 'New Virtual Machine' wizard (Jeremy Perry, Tim Allen, Cole Robinson)
  • Option to remove storage when deleting a virtual machine.
  • File browser[3] 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.
  • Bug fixes and minor improvements.

New Release virtinst 0.4.3

Cole Robinson announce[1] a new Package-x-generic-16.pngpython-virtinst release, version 0.400.3.

virtinst is a module that helps build and install libvirt based virtual machines. It currently supports KVM, QEmu and Xen virtual machines. Package includes several command line utilities, including virt-install (build and install new VMs) and virt-clone (clone an existing virtual machine).

This is largely a bug fix release.

Fedora Xen List

This section contains the discussion happening on the fedora-xen list.

dom0 Kernel: Better, Still Not Ready

Itamar Reis Peixoto reported[1] success with Michael Young's latest Package-x-generic-16.pngkernel build[2] and wondered when it could be released.

Michael explained, "The current plan is to wait until basic dom0 support makes it into the vanilla kernel, which should happen for 2.6.30, and then decide if dom0 can be enabled and if the patches for full dom0 support can safely be added without affecting ordinary operation."

"At the moment there are still things that are broken such as X support in some cases, and there are also Fedora patches that have been omitted because they were tricky to merge, so it is too early to start adding dom0 support to official Fedora kernels."

Missing Hypervisor Capabilities Restored

There was progress on a bug discovered[1] last week. This missing file /sys/hypervisor/properties/capabilities has been restored[2], however a bug[3] remained[4] in libvirt or virt-install.

Libvirt List

This section contains the discussion happening on the libvir-list.

Snapshot Support Discussed

In an attempt to make it easier to backup KVM windows guests, Matt McCowan created[1] a checkpoint virsh function. "Modelled on the virDomainSave[2] function it takes an optional script which it will execute (and pass the name of the domain as an argument) while the domain is paused, then resume the domain." Within this script, a backup of the guest domain could be created.

The patch was seen as too ad-hoc, and not accepted as-is. Daniel Veillard commented[3] "I think this can help administrators in a controlled situation, but I'm hoping a real snapshotting API will be possible at some point where Package-x-generic-16.pnglibvirt goes though the list of storage resources used by the domain and properly make a snapshot using a storage API or return an error if that's not possible."

Daniel P. Berrange described[4] what he would like to see. "In terms of API I think I'd like to see snapshotting[5] available as part of a more generic save/restore API. I tend to think of the current API as providing 'unmanaged save/restore'". Libvirt does not track saved images, so does not know if a snapshot is available to be started at the restart of libvirtd."

"Thus I think the first step towards a general snapshot facility would be to provide an API for 'managed save/restore' where we explicitly track saved images." "With this, you could configure libvirtd, so that when starting up, it" would "see if the guest was suspended before the previous host shutdown, and if so, then restore from that saved image automatically.[6] Or make it skip autostart completely, if any save images exist, and allow an admin defined initscript to do auto restore from the save image."

Memory Ballooning Support for QEMU

Daniel Berrange patched[1] the libvirt QEMU driver to fully support memory ballooning. "Memory ballooning allows you to have your guest dynamically change it’s memory usage by evicting unused memory during runtime. This is a useful feature because it reduces the impact your guest can have on memory usage of your host by giving up unused memory back to the host."[2]