The patch that added the nftables backend for virtual networks left iptables as the default backend when both nftables and iptables are installed. The only functional difference between the two backends is that the nftables backend doesn't add any rules to fix up the checksum of DHCP packets, which will cause failures on guests with very old OSes (e.g. RHEL5) that have a virtio-net network interface using vhost packet processing (the default), connected to a libvirt virtual network, and configured to acquire the interface IP using DHCP. Since RHEL5 has been out of support for several years already, we might as well start off nftables support right by making it the default. Distros that aren't quite ready to default to nftables (e.g. maybe they're rebasing libvirt within a release and don't want to surprise anyone with an automatic switch from iptables to nftables) can simply run meson with "-Dfirewall_backend=iptables" during their official package build. In the extremely unlikely case that this causes a problem for a user, they can work around the failure by adding "<driver name='qemu'/> to the guest <interface> element. Signed-off-by: Laine Stump <laine@redhat.com> Reviewed-by: Daniel P. Berrangé <berrange@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
Instructions on building and installing libvirt can be found on the website:
https://libvirt.org/compiling.html
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:
- users@lists.libvirt.org (for user discussions)
- devel@lists.libvirt.org (for development only)
Further details on contacting the project are available on the website: