Michael, In Ubuntu we're seeing a bug in qemu-kvm 1.0 where networking stops working. It's described here:
https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/997978 We've not been able to reproduce it ourselves, but the users who are experiencing it say that it's fixed in 1.1. I've found this series of commits: a821ce5 virtio: order index/descriptor reads 92045d8 virtio: add missing mb() on enable notification a281ebc virtio: add missing mb() on notification where particularly the last one looks like a likely fix for the problem. The commit message isn't entirely clear about the symptoms it's meant to fix, even though the behind-the-covers explanation is very thorough. It's not clear to me, for instance, if the network would stop working or if you'd just lose a couple of network packets? The commit message suggests it only happens on a very specific processor type. Do you happen to remember which one? If it matches what our affected users see, that could be clue as to whether this is the same problem. Thanks in advance for your time. -- Soren Hansen Ubuntu Developer http://www.ubuntu.com/ OpenStack Developer http://www.openstack.org/