6c17606b7c
Prior to commit 55ce6564634 (first in libvirt 4.6.0), the XML sent to virDomainAttachDeviceFlags() was parsed only once, and the results of that parse were inserted into both the live object of the running domain and into the persistent config. Thus, if MAC address was omitted from in XML for a network device (<interface>), both the live and config object would have the same MAC address. Commit 55ce6564634 changed the code to parse the incoming XML twice - once for live and once for config. This does eliminate the problem of PCI (/scsi/sata) address conflicts caused by allocating an address based on existing devices in live object, but then inserting the result into the config (which may already have a device using that address), BUT it also means that when the MAC address of a network device hasn't been specified in the XML, each copy will get a different auto-generated MAC address. This results in the MAC address of the device changing the next time the domain is shutdown and restarted, which creates havoc with the guest OS's network config. There have been several discussions about this in the last > 1 year, attempting to find the ideal solution to this problem that makes MAC addresses consistent and accounts for all sorts of corner cases with PCI/scsi/sata addresses. All of these discussions fizzled out because every proposal was either too difficult to implement or failed to fix some esoteric case someone thought up. So, in the interest of solving the MAC address problem while not making the "other address" situation any worse than before, this patch simply adds a qemuDomainAttachDeviceLiveAndConfigHomogenize() function that (for now) copies the MAC address from the config object to the live object (if the original xml had <mac address='blah'/> then this will be an effective NOP (as the macs already match)). Any downstream libvirt containing upstream commit 55ce6564634 should have this patch as well. https://bugzilla.redhat.com/1783411 Signed-off-by: Laine Stump <laine@redhat.com> Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Libvirt API for virtualization
Libvirt provides a portable, long term stable C API for managing the virtualization technologies provided by many operating systems. It includes support for QEMU, KVM, Xen, LXC, bhyve, Virtuozzo, VMware vCenter and ESX, VMware Desktop, Hyper-V, VirtualBox and the POWER Hypervisor.
For some of these hypervisors, it provides a stateful management daemon which runs on the virtualization host allowing access to the API both by non-privileged local users and remote users.
Layered packages provide bindings of the libvirt C API into other languages including Python, Perl, PHP, Go, Java, OCaml, as well as mappings into object systems such as GObject, CIM and SNMP.
Further information about the libvirt project can be found on the website:
License
The libvirt C API is distributed under the terms of GNU Lesser General
Public License, version 2.1 (or later). Some parts of the code that are
not part of the C library may have the more restrictive GNU General
Public License, version 2.0 (or later). See the files COPYING.LESSER
and COPYING for full license terms & conditions.
Installation
Libvirt uses the GNU Autotools build system, so in general can be built and installed with the usual commands, however, we mandate to have the build directory different than the source directory. For example, to build in a manner that is suitable for installing as root, use:
$ mkdir build && cd build
$ ../configure --prefix=/usr --sysconfdir=/etc --localstatedir=/var
$ make
$ sudo make install
While to build & install as an unprivileged user
$ mkdir build && cd build
$ ../configure --prefix=$HOME/usr
$ make
$ make install
The libvirt code relies on a large number of 3rd party libraries. These will
be detected during execution of the configure script and a summary printed
which lists any missing (optional) dependencies.
Contributing
The libvirt project welcomes contributions in many ways. For most components the best way to contribute is to send patches to the primary development mailing list. Further guidance on this can be found on the website:
https://libvirt.org/contribute.html
Contact
The libvirt project has two primary mailing lists:
- libvirt-users@redhat.com (for user discussions)
- libvir-list@redhat.com (for development only)
Further details on contacting the project are available on the website: