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Physnet VLAN: More than one external network exists

asked 2016-04-05 08:41:39 -0500

Kevin gravatar image


we are using physnet (br-ex) for external connections to OpenStack. All networks should use a VLAN-ID so we can plug in devices by using PVID on most switches.

I created several networks on our infrastructure like this:

neutron net-create wan-01 --provider:network_type vlan --provider:physical_network physnet --router:external --shared
neutron net-create wan-02 --provider:network_type vlan --provider:physical_network physnet --router:external --shared

What does external realy mean? We have multiple external subnets (pseudo physical by VLAN), so we need the L3-Agent to host multiple networks.

Currently the logs are flooded by "More than one external network exists.". What is the right approach?

Thank you.

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answered 2016-04-05 09:45:20 -0500

dbaxps gravatar image

updated 2016-04-05 10:01:08 -0500


That is  just a sample for Network Node setup. Proposed approach for OVS configuration &&
 L3 router, in particular, is not bind to RDO in any way
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Thanks for your answer. This workaround does not realy look like a good solution. Why do I need to setup an external connection per VLAN? This would mean, if I have 2.000 customers (each with one private tenant VLAN), I need to set up 2.000 physnets.

Kevin gravatar imageKevin ( 2016-04-05 15:58:11 -0500 )edit

Wait ! You invoke external network provider of VLAN not FLAT type. It means that each one of created external network is supposed to be vlan tagged. Do you realize what you are doing ?
Single physical wire may be set up for 100-2100 vlan tags and corresponding trunk port on the router as well.

dbaxps gravatar imagedbaxps ( 2016-04-05 16:27:53 -0500 )edit

I don't get what you mean. We use QinQ for this, br-ex is only used for customer-networks. We can host many VLANs which we untag on our customer-switch (switch which the colo-racks are connected to).

Kevin gravatar imageKevin ( 2016-04-05 17:21:56 -0500 )edit

I want to do the following:

Kevin gravatar imageKevin ( 2016-04-05 17:32:30 -0500 )edit

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Asked: 2016-04-05 08:41:39 -0500

Seen: 927 times

Last updated: Apr 05 '16