Comment 60 for bug 584048

I have the same 4-second bridge freeze when using LXC containers and lxc-start or lxc-stop. (I am using a custom script to create my LXC containers.) I saw the reference to this above:

https://www.redhat.com/archives/libvir-list/2010-July/msg00450.html

I changed my custom script from this:

MACADDR="00:16:3e:"`head /dev/urandom | md5sum | sed -r 's/^(.{6}).*$/\1/; s/([0-9a-f]{2})/\1:/g; s/:$//;'`

...to this:

MACADDR="fe:16:3e:"`head /dev/urandom | md5sum | sed -r 's/^(.{6}).*$/\1/; s/([0-9a-f]{2})/\1:/g; s/:$//;'`

...and now the freezing is gone.

Since this is my own custom script, I'm not sure what package it would belong to. Just be aware that this is a fundamental "bridge" issue and not limited to libvirt, KVM. It shows up with LXC and probably any other system where you add a new MAC.