When destroying a network, the network driver has always assumed that it knew what firewall rules had been added as the network was started. This was usually correct - I only recall one time in the past that the firewall rules added by libvirt were changed. But if the exact rules used for a network *were* ever changed from one build/version of libvirt to another, then we would end up attempting to remove rules that hadn't been added, and could possibly *not* remove rules that had been added. The solution to this to not make such brash assumptions about the past, but instead to save (in the network status object at network start time) a list of all the rules needed to remove the rules that were added for the network, and then use that saved list during network destroy to remove exactly what was previous added. Beyond making net-destroy more precise, there are other benefits: 1) We can change the details of the rules we add for networks from one build/release of libvirt to another and painlessly upgrade. 2) The user can switch from one firewall backend to another by simply changing the setting in network.conf and restarting libvirtd/virtnetworkd. In both cases, the restarted libvirtd/virtnetworkd will remove all the rules that had been previously added (based on the network status), and then add new rules (saving the new removal commands back into the network status) 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: