tapXXX already exists on bridge brqXXX with linuxbridge ml2 plugin

asked 2014-11-26 08:40:46 -0600

updated 2014-11-26 23:29:52 -0600

I'm using ML2 plugin with linuxbridges on Juno release. My requirement is to use "flat" networks with public IPs ( in the subnet. "physical_interface_mappings" in ML2:linuxbridge plugin is as simple as ['physnet1:eth0.4035']. Here, eth0.4035 is a 4035 vlan tagged interface on CentOS.

When I execute "nova boot", I can see

  • instance getting the IP assigned
  • Neutron port also gets created.
  • The brqXXX and tabXXX interface also gets created.

But, linuxbridge agent on compute node complains about tapXXX already existing. I'm confused because linuxbridge is the one that created the interface so how does it not know about the tap device.

Full log can be seen here: http://paste.openstack.org/show/138845/ . I'll appreciate any kind of guesses and possible solutions.

"nova list" shows the error as: "Build of instance 6e4ddb50-8630-4a4d-b400-477517721de7 aborted: Failed to allocate the network(s), not rescheduling.".

edit retag flag offensive close merge delete


It is nova-compute that creates the tap interface (and bridge too if necessary). I think the problem is with nova-compute - check its log or post it too. My guess is that it timed out waiting for a callback from neutron to say that port has been bound.

darragh-oreilly gravatar imagedarragh-oreilly ( 2014-11-27 02:51:50 -0600 )edit