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<div class="moz-cite-prefix">Le 08/07/2015 18:35, Gustavo Randich a
écrit :<br>
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<div>Hi,<br>
<br>
We are trying to figure out how to transition from a
network model using nova-network and a single VLAN to a
model using Neutron and multiple VXLAN tunnels.<br>
<br>
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<div>The main issue is not how to configure and setup the
tunnels, but how to expose the new virtual machines born
inside the tunnels to our "legacy", non-VXLAN,
non-Openstack networks, i.e. DNS serrvers, databases,
hardware load balancers, monitoring/metrics servers, etc.<br>
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<br>
What I understand from Neutron use of VXLAN/GRE, is that it's only
for encapsulating L2 traffic into L3 from tenant/project to
networking node(s). It permits to bypass the L2 configuration (i.e.
switches) that exists between your servers.<br>
<br>
See:
<a class="moz-txt-link-freetext" href="http://docs.openstack.org/networking-guide/_images/scenario-legacy-ovs-flowns1.png">http://docs.openstack.org/networking-guide/_images/scenario-legacy-ovs-flowns1.png</a><br>
<br>
The decision to route the packet is made by the qrouter/L3 agent on
the networking node(s). <br>
Eventually you can create a L2 only network inside Neutron and
assign a gateway that is a physical device outside your servers.<br>
<br>
See:
<a class="moz-txt-link-freetext" href="http://docs.openstack.org/networking-guide/deploy_scenario4a.html">http://docs.openstack.org/networking-guide/deploy_scenario4a.html</a><br>
<br>
I'm also currently on the task to migrate a full nova-network VLAN
network to a Neutron VLAN topology for fixed IPs and VXLAN/GRE
topology for floating IPs.<br>
<br>
Hope Neutron specialists are around :)<br>
<br>
See you,<br>
<br>
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