[openstack-dev] [neutron][nova] some conflicts in bridge-mapping in linuxbridge
skywalker.nick at gmail.com
Thu Jul 30 09:01:05 UTC 2015
Currently, I'm implementing this blueprint:
This function enables a user-defined pre-existed bridge to connect
instances , rather than creating a new bridge that may break security
rule of some companies.
Neutron code has been done recently, but I find that it is really
difficult to implement due to Nova.
Nova hard-code 'brq' + net-id as bridge name in libvirt configuration.
def _nw_info_build_network(self, port, networks, subnets):
1530 elif vif_type == network_model.VIF_TYPE_BRIDGE:
1531 bridge = "brq" + port['network_id']
For example, in flat network type, when Neutron loads a pre-existed
user-defined bridge called 'br-eth1' and would like to let it connect
the instances, it will fail because Nova writes 'brq-net-id' into
libvirt conf file.
I have several solutions for that.
(1) Add the same 'bridge-mapping' configuration in nova.conf for
nova-compute. It is almost the same implementation in OVS-agent.
When nova needs bridge name to process, it first reads that
configuration and then decide which bridge to use.
(2) Let Neutron decide interface name (tap-xxx) and bridge name
(brq-xxx), not Nova. As a result, when creating port, Neutron return
interface name and bridge name to Nova, so Nova has the right device
name to process. This helps Nova get rid of hard-code, but need lots
of work on it.
Pls give some advice. Thanks a lot.
Li Ma (Nick)
More information about the OpenStack-dev