Il 22/03/2013 22:37, Corey Bryant ha scritto: > Is it desirable to change a mac address under the covers?
This is the TAP mac address. It is unrelated to the guest's MAC address. It is a random link-local address, all this patch does is make it less random. > Also it seems like this might be better if it was optional. > qemu-bridge-helper can take command line options like this: > > -net tap,helper="/usr/local/libexec/qemu-bridge-helper --br=br0" > > Perhaps adding a --macaddr option is a better approach? Adding a --macaddr=00:11:... option to force a _particular_ MAC address could also be useful (if only to help associating guests' MAC addresses with tap interfaces; the only difference would be the initial 0xFE byte). But it is not easily done in QEMU because MAC addresses are a -device option, not a -netdev option. This patch fixes the real issue that, when the bridge changes MAC address, there is a small but significant network downtime. See libvirt commit 6ea90b843eff95be6bcbb49a327656fc6f6445ef for reference. What would you make it conditional on? Paolo
