mirror of
https://gitlab.com/libvirt/libvirt.git
synced 2025-03-20 07:59:00 +00:00
fc7b23db02
Just as it is possible to delete a bridge device with the netlink RTM_DELLINK message, one can be created with the RTM_NEWLINK message. Because of differences in the format of the message, it's not as straightforward as with virNetlinkDelLink() to create a single utility function that can be used to create any type of interface, so the new netlink version of virNetDevBridgeCreate() does its own construction of the netlink message and calls virNetlinkCommand() itself. This doesn't provide any extra functionality, just provides symmetry with the previous commit. NB: We *could* alter the API of virNetDevBridgeCreate() to take a MAC address, and directly program that mac address into the bridge (by adding an IFLA_ADDRESS attribute, as is done in virNetDevMacVLanCreate()) rather than separately creating the "dummy tap" (e.g. virbr0-nic) to maintain a fixed mac address on the bridge, but the commit history of virnetdevbridge.c shows that the presence of this dummy tap is essential in some older versions of the kernel (between 2.6.39 and 3.1 or 3.2, possibly?) to proper operation of IPv6 DAD, and I don't want to take the chance of breaking something that I don't have the time/setup to test (my RHEL6 box is at kernel 2.6.32-544, and the next lowest kernel I have is 3.17)
LibVirt : simple API for virtualization
Libvirt is a C toolkit to interact with the virtualization capabilities
of recent versions of Linux (and other OSes). It is free software
available under the GNU Lesser General Public License. Virtualization of
the Linux Operating System means the ability to run multiple instances of
Operating Systems concurrently on a single hardware system where the basic
resources are driven by a Linux instance. The library aim at providing
long term stable C API initially for the Xen paravirtualization but
should be able to integrate other virtualization mechanisms if needed.
Daniel Veillard <veillard@redhat.com>