port of an instance is automatically added to br-int instead of br-ex

asked 2014-01-07 16:04:18 -0600

darkwave gravatar image


I have created two bridged (br-int and br-ex) with the ovs-vsctl tool. Then I created a flat network:

neutron net-create flat --provider:network_type flat --provider:physical_network physnet1

I the file /etc/neutron/plugins/openvswitch/ovs_neutron_plugin.ini the physnet1 interface is mapped to br-ex

bridge_mappings = physnet1:br-ex

When I now create an instance within openstack (of course connected to the flat network), neutron automatically creates a port in br-int instead of br-ex. (marked with **)

ovs-vsctl show

Bridge br-int
    Port br-int
        Interface br-int
            type: internal
    Port "int-br-eth0"
        Interface "int-br-eth0"
    Port "int-br2-ex"
        Interface "int-br2-ex"
    Port int-br-ex
        Interface int-br-ex
    Port "int-br0"
        Interface "int-br0"
    **Port "qvo14526899-a9"
        tag: 1
        Interface "qvo14526899-a9"**

Bridge br-ex
    Port "eth0"
        Interface "eth0"
    Port br-ex
        Interface br-ex
            type: internal
    Port phy-br-ex
        Interface phy-br-ex
ovs_version: "1.11.0"

How do I say neutron to automatically add the port to br-ex?

Thank you Darkwave

edit retag flag offensive close merge delete

2 answers

Sort by ยป oldest newest most voted

answered 2014-01-09 04:15:14 -0600

darkwave gravatar image

Thank you marvel for the answer. So I understand correct, that openstack always first uses br-int for connecting virtual machines? And than br-int goes out to other networks?

I think I have a setup where I don't really need a router. What I want is that my virtual machines directly have public IP Addresses. But I'm not sure how to realize that. It is explained in this picture: http://s15.postimg.org/kgxmosz0r/flatopenstack.jpg

do I need there a router or can i somehow achieve that with a software bridge on host level? Any idea?

best regards

edit flag offensive delete link more

answered 2014-01-07 21:46:08 -0600

marvel gravatar image

normally a new instance's interface(tap-xxx) is connected via qbr-xxx and qvo-xxx port, the qvo-xxx port is then attached to the br-int bridge, so data is first transmited to br-int bridge, so the configuration seems ok.

but if your vm need to go outside the virtual network, you should be create a router connecting a qg-xxx(external gateway) port in the br-ex and a qr-xxx(internal gateway) in the br-int. I guess you have not created the router yet.

edit flag offensive delete link more

Get to know Ask OpenStack

Resources for moderators

Question Tools

1 follower


Asked: 2014-01-07 16:04:18 -0600

Seen: 2,373 times

Last updated: Jan 09 '14