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confused about physnet [closed]

asked 2016-09-15 16:44:56 -0600

updated 2016-09-18 14:24:43 -0600

using packstack/centos7/mitaka

configured packstack like so:


Im confused about the CONFIG_NEUTRON_OVS_BRIDGE_MAPPINGS as the only place i find it is the openvswitch_agent.ini

/etc/neutron/plugins/ml2/openvswitch_agent.ini:bridge_mappings =brex:br-ex,br10:br-10,br15:br-15

so my question is....

If my physical interfaces are:
bond0.10 (vlan 10) bridge br-10
bond0.15 (vlan 15) bridge br-15 
em4 (flat network) bridge br-ex

what the hell is brex,br10 and br15? (i made these up btw because i dont understand what it needs in the previous OVS field)

What should this be if not brex?

And to follow all these questions, I have no idea how to move forward.....

In these next commands, what should --provider:physical_network= command look like?

. /root/keystonerc_admin  
neutron net-create external_10 --provider:network_type flat --provider:physical_network=br10 --router:external --shared
neutron subnet-create --name subnet_10 --disable-dhcp --allocation-pool=start=,end= --gateway= external_10
neutron router-create external_router_10
neutron router-gateway-set external_router_10 external_10

neutron net-create external_15 --provider:network_type flat --provider:physical_network=br15 --router:external --shared
neutron subnet-create --name subnet_15 --enable-dhcp --allocation-pool=start=,end= --gateway= external_15
neutron router-create external_router_15
neutron router-gateway-set external_router_15 external_15

neutron net-create external_999 --provider:network_type flat --provider:physical_network=brex  --router:external --shared
neutron subnet-create --name subnet_999 --disable-dhcp --allocation-pool=start=,end= --gateway= external_999
neutron router-create external_router_999
neutron router-gateway-set external_router_999 external_999
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Closed for the following reason the question is answered, right answer was accepted by bcollins
close date 2016-09-18 23:42:35.166045

2 answers

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answered 2016-09-18 14:28:42 -0600

updated 2016-09-18 23:42:16 -0600

I believe I have it now.brex is the reference point for openstack to call to create the link between neutron and openvswitch (correct if wrong) .

I have always named this field the same as my bridge until now. Amazing how little you know when you think you know what's going on!!!!!

neutron net-create external_999 --provider:network_type flat --provider:physical_network=brex  --router:external --shared
neutron subnet-create --name subnet_999 --enable-dhcp --allocation-pool=start=,end= --gateway= external_999
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answered 2016-09-17 00:52:00 -0600

Tamil gravatar image

updated 2016-09-17 00:53:19 -0600


The br-ex, br0 ,etc are virtual interface setup created by OVS-switch to route traffic between the virtual instance and to route traffic from instance to outer network, To understand this commands in a better way , checkout this video link text

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can you relate it to the names i have posted so I can understand. EVERYTHING i read says physnet or br-ex in the examples. I want to know what this equates to in this config? Are these the points I need to reference in my next commands?

bcollins gravatar imagebcollins ( 2016-09-18 14:23:30 -0600 )edit

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Asked: 2016-09-15 16:44:56 -0600

Seen: 821 times

Last updated: Sep 18 '16