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Flat plus VLAN on same compute node

asked 2013-10-24 10:03:44 -0500

murp3433 gravatar image

updated 2013-10-24 11:35:27 -0500

darragh-oreilly gravatar image

I have a working 4 node grizzly VLAN installation. Controller, cinder, compute, and network. The problem is that i need to create a flat network where i can have publicly routable ip's directly assigned to guests. Is this possible on the same compute node/physnet or do i need to have a second compute node just for the flat network?

Thank you!

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nova-network or neutron? With neutron, yes with ovs or linuxbridge plugins (at least). Don't know about nova-network.

darragh-oreilly gravatar imagedarragh-oreilly ( 2013-10-24 10:17:19 -0500 )edit

Thanks! Sorry, quantum with ovs. I tried a cpl ways but i cant seem to get it. Do i need a separate interface ethx and assign it to physnet2? I also tried just setting up a single flat network and couldnt get that to work either. Do i need to change the configs to use a flat network? Right now i have physnet1 mapped to br-eth1 with vlans. I got the complicated setup (vlans) no problem, but i cant seem to get the simplest one to work :)

murp3433 gravatar imagemurp3433 ( 2013-10-24 10:56:09 -0500 )edit

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answered 2013-10-24 11:30:26 -0500

darragh-oreilly gravatar image

Yes, you will need a separate interface enslaved in a separate bridge for the flat network. The weird thing is that you have to include the symbolic name for the flat network in the list of vlan ranges, eg physnet2 here:

# ovs_quantum_plugin.ini on controller, netnodes and compute-nodes
network_vlan_ranges = physnet1:1000:1999, physnet2
bridge_mappings = physnet1:br-vlans, physnet2:br-flat

Then you should be able to create networks like:

quantum net-create net1 --provider:network_type vlan \
    --provider:physical_network physnet1 \
    --provider:segmentation_id 1234

quantum net-create net2 --provider:network_type flat \
    --provider:physical_network physnet2
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Thank you so much. So for a test, if i remove the vlan range numbers and just have network_vlan_ranges = physnet1 bridge_mappings = physnet1:br-flat, i should be able to create a flat shared network with a public netblock that will be assigned to the vm's, just like i would for a vlan network. correct?

murp3433 gravatar imagemurp3433 ( 2013-10-24 12:30:46 -0500 )edit

Ok one more question. Now when i create a vm it doesnt have internet access. If i setup the subnet with dhcp i can ping the dhcp ip but cant ping the external router or anything else. Does the network node need to have routes and ip's set up for flat to work?

murp3433 gravatar imagemurp3433 ( 2013-10-24 14:45:13 -0500 )edit

So you are trying to get external (out-of-openstack) access via a real router (non-quantum) that is connected to the segment that backs the flat network? Then the ip address of this router should be in the CIDR of the quantum subnet for this quantum network.

darragh-oreilly gravatar imagedarragh-oreilly ( 2013-10-25 01:53:27 -0500 )edit

Yes. I have a few public netblocks and i want the vm's in my openstack install to have public ip's directly assigned. So external network is the router is and vm's get are you saying that the external nic of the network node needs to be set to an available address in that network?

murp3433 gravatar imagemurp3433 ( 2013-10-25 06:37:28 -0500 )edit

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Asked: 2013-10-24 10:03:44 -0500

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Last updated: Oct 24 '13