From Fedora Project Wiki


In this section, we cover discussion of Fedora virtualization technologies on the @fedora-virt, @fedora-xen-list, and @libvirt-list lists.

Contributing Writer: Dale Bewley

Fedora Virtualization List

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

Guest Bridge Configuration with libvirt and netcf

Andrés García thought[1] he read somewhere that with Fedora 12 there was going to be a way to configure virtual network bridges automagically", but was only aware of the manual[2] means of configuration.

It is possible in to configure bridges using virsh thanks to the Network Interface Management[3] feature and Package-x-generic-16.pngnetcf[4]. However, the process is manual and not in the GUI. Dale Bewley blogged[5] about how to manually create a bridge in Fedora 12 using virsh.

Support for Package-x-generic-16.pngvirt-manager integration is targeted[6] for Fedora 13.

New Release libguestfs 1.0.78

Richard Jones announced[1] version 1.0.78 of Package-x-generic-16.pnglibguestfs[2], the library for accessing and modifying virtual machine filesystems.

New Features:

  • FUSE support so you can mount guest filesystems in the host [3]
  • Support for btrfs, gfs, gfs2, hfs, hfs+, nilfs2, jfs, reiserfs, xfs[4]
  • Support for huge (multi-exabyte) sparse virtual disks[5]
  • New partitioning API, supports GPT and more[6]
  • New tools:
  • Windows Registry support, tools and library[11] [12]
  • OCaml bindings for virt-inspector
  • RELAX NG schema for virt-inspector
  • New APIs: utimens, vfs_type, truncate, truncate_size, lchown, lstatlist, lxattrlist, readlinklist, case_sensitive_path, find0, mkfs_b, mke2journal, and more ...
  • New program: OCaml viewer[13]
  • Allow stdout to be redirected when running guestfish remotely (Matt Booth).
  • Remove requirement for vmchannel support in qemu (horray!) and the tricky main loop code.

Fedora Xen List

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

No Xen dom0 in Fedora 12 Hopefully 13

Zhang Enming was disappointed[1] to learn[2] the pv_ops dom0 support[3] for hosting Xen guests, dropped in Fedora 9, is still not present in Fedora 12. Zhang referenced numerous videos documenting success in creating "a fully working Xen pv-ops dom0 Fedora 11 host operating system."

While there are experimental patches which may be applied[4] [5] to the kernel to enable support for dom0, they are not yet in the upstream kernel which forms the basis the Fedora kernel package.

It was decided[6] two years ago this month that Fedora "simply cannot spend more time forward porting Xen kernels" and "the plan is to re-focus 100% of all Xen kernel efforts onto paravirt_ops." See FWN#137.[7]

Pasi Kärkkäinen noted[8] "pv_ops dom0 kernel has only recently started working for many/most people, so it was too late for F12 release" and "There are still some missing features, most notably missing blktap2 support for tap:aio: file-based images."

Libvirt List

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

Keeping Guest Configurations in Sync on Multiple Hosts

Thomas Treutner asked[1] "is there any best-practice how to keep VM definitions in sync across a couple of hosts? Is it reasonable to put /etc/libvirt/qemu/ on a NFS share?"

Matthias Bolte explained[2] "No, it's not safe to share /etc/libvirt/qemu/", but also didn't find it necessary to keep the configs in sync. "A migrated domain stays defined on the source node and is transient on the destination node. A transient domain has no persistent config on its node and is lost when destroyed."

Matthias mentioned a patch[3] to the virDomainMigrate[4] function by Chris Lalancette which will be in Package-x-generic-16.pnglibvirt 0.7.3. The patch adds a new flag which will allow domains to be migrated persistently. Version 0.7.3 is targeted[5] for release on November 20th.