Comment 21 for bug 1527675

I tried devstack again, with the latest (commit ffb96b8 - Merge "always default to floating ips for validation"). I removed all the neutron and nova config file sections from my local.conf, instead adding `Q_ML2_PLUGIN_PATH_MTU=1500` to the localrc part. So far I have just done an all-on-one-node devstack like this. It produced a system where the network interface inside the VM has an MTU of 1450 (which is correct, since this is a VXLAN configuration). All the other MTUs are 1500; these include br-int, br-ex, br-tun, qbr$id, qbo$id, qvb$id, and tap$id on the host, and qr-$id and qg-$id in the Neutron router's network namespace.

I wonder whether those are entirely correct. The traffic through the Neutron router gets a VXLAN header added to it, right?

Experimentally I have seen no end-to-end problem yet. I have made an SSH connection from the host to the VM, used `scp` (in the VM) to copy a 400 KB file from the VM to an external server, and then used `scp` (in the VM) to copy the file back into the VM. This would not have succeeded in my earlier configurations.