Ubuntu
libvirt package

  1. Bug #1218959
  2. Comment #0

Comment 0 for bug 1218959

Revision history for this message
Michael Cook (michaelcook-mjc) wrote :

A recent kernel update (Apr 2013) has made it's way to U12.04.2 LTS (approx June-Aug 2013) and has stopped the (default) behaviour of automatically forwarding multicast traffic over virbr#. Some updates the bridge subsystem now, by default, disable multicast traffic without IGMP Querier being enabled on that bridge.

The corresponding Fedora/RHEL bug tracks the progress/updates of this specific change in relation to Fedora.
https://bugzilla.redhat.com/show_bug.cgi?id=880035

(I have yet to find a similar bug report in Ubuntu so I have created this bug to help the Ubuntu community identify multicast issues that may arise since April 2013 in U12.04 LTS and presumably other Ubuntu releases as backports are made and break regression testing.)

Using the latest patches in U12.04.2 LTS this following addition, with some modifications, can be made to the udev rules will enable multicast on virbr# bridge:
https://bugzilla.redhat.com/show_bug.cgi?id=880035#c38

While this is an improvement/correction to KVM bridge networking it has broken existing functionality in U12.04.2 LTS and broke regressed functionality that once worked.