<div dir="ltr">Hi Kevin,<div><br></div><div>The current method outlined in [1] is to manually assign networks to dhcp agents. I need to be able to kill the node running the dhcp agent and start it up on another node without manual intervention. Someone else pointed me to the <span style="font-family:arial,sans-serif;font-size:13px">dhcp_agents_per_network option which I'm looking into now.</span></div><div><br></div><div>[1] <a href="http://docs.openstack.org/trunk/config-reference/content/multi_agent_demo_configuration.html" target="_blank">http://docs.openstack.org/trunk/config-reference/content/multi_agent_demo_configuration.html</a> </div><div><br></div><div><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Mon, Oct 20, 2014 at 8:17 PM, Kevin Benton <span dir="ltr"><<a href="mailto:blak111@gmail.com" target="_blank">blak111@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><p dir="ltr">The current suggested way for DHCP agent fault tolerance is multiple agents per network. Is there a reason you don't want to use that option? </p><div class="HOEnZb"><div class="h5">
<div class="gmail_quote">On Oct 20, 2014 5:13 PM, "Noel Burton-Krahn" <<a href="mailto:noel@pistoncloud.com" target="_blank">noel@pistoncloud.com</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">Thanks, Robert.<div><br></div><div>So, ML2 needs the host attribute to match to bind the port. My other requirement is that the dhcp agent must be able to migrate to a new host on failover. The issue there is that if the dhcp service starts on a new host with a new host name, then it will not take over the networks that were served by the old host name. I'm looking for a way to start the dhcp agent on a new host using the old host's config.</div><div><br></div><div>--</div><div>Noel</div><div><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Mon, Oct 20, 2014 at 11:10 AM, Robert Kukura <span dir="ltr"><<a href="mailto:kukura@noironetworks.com" target="_blank">kukura@noironetworks.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">
Hi Noel,<br>
<br>
The ML2 plugin uses the binding:host_id attribute of port to control
port binding. For compute ports, nova sets binding:host_id when
creating/updating the neutron port, and ML2's openvswitch mechanism
driver will look in agents_db to make sure the openvswitch L2 agent
is running on that host, and that it has a bridge mapping for any
needed physical network or has the appropriate tunnel type enabled.
The binding:host_id attribute also gets set on DHCP, L3, and other
agents' ports, and must match the host of the openvswitch-agent on
that node or ML2 will not be able to bind the port. I suspect your
configuration may be resulting in these not matching, and the DHCP
port's binding:vif_type attribute being 'binding_failed'.<br>
<br>
I'd suggest running "neutron port-show" as admin on the DHCP port to
see what the values of binding_vif_type and binding:host_id are, and
running "neutron agent-list" as admin to make sure there is an L2
agent on that node and maybe "neutron agent-show" as admin to get
that agents config details.<br>
<br>
-Bob<div><div><br>
<br>
<br>
<div>On 10/20/14 1:28 PM, Noel Burton-Krahn
wrote:<br>
</div>
</div></div><blockquote type="cite"><div><div>
<div dir="ltr">I'm running OpenStack Icehouse with Neutron
ML2/OVS. I've configured the ml2-ovs-plugin on all nodes with
host = the IP of the host itself. However, my dhcp-agent may
float from host to host for failover, so I configured it with
host="floating". That doesn't work. In this case, the
ml2-ovs-plugin creates a namespace and a tap interface for the
dhcp agent, but OVS doesn't route any traffic to the dhcp
agent. It *does* work if the dhcp agent's host is the same as
the ovs plugin's host, but if my dhcp agent migrates to another
host, it loses its configuration since it now has a different
host name.
<div><br>
</div>
<div>So my question is, what does host mean for the ML2 dhcp
agent and host can I get it to work if the dhcp agent's host
!= host for the ovs plugin?</div>
<div><br>
</div>
<div>Case 1: fails: running with dhcp agent's host = "floating",
ovs plugin's host = IP-of-server</div>
<div>dhcp agent is running in netns created by ovs-plugin</div>
<div>dhcp agent never receives network traffic</div>
<div><br>
</div>
<div>Case 2: ok: running with dhcp agent's host = ovs plugin's
host = IP-of-server</div>
<div>
<div>dhcp agent is running in netns created by ovs-plugin
(different tap name than case 1)</div>
</div>
<div>dhcp agent works</div>
<div><br>
</div>
<div>--</div>
<div>Noel</div>
<div><br>
</div>
<div><br>
</div>
<div><br>
</div>
<div> </div>
</div>
<br>
<fieldset></fieldset>
<br>
</div></div><pre>_______________________________________________
OpenStack-dev mailing list
<a href="mailto:OpenStack-dev@lists.openstack.org" target="_blank">OpenStack-dev@lists.openstack.org</a>
<a href="http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev" target="_blank">http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev</a>
</pre>
</blockquote>
<br>
</div>
<br>_______________________________________________<br>
OpenStack-dev mailing list<br>
<a href="mailto:OpenStack-dev@lists.openstack.org" target="_blank">OpenStack-dev@lists.openstack.org</a><br>
<a href="http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev" target="_blank">http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev</a><br>
<br></blockquote></div><br></div>
<br>_______________________________________________<br>
OpenStack-dev mailing list<br>
<a href="mailto:OpenStack-dev@lists.openstack.org" target="_blank">OpenStack-dev@lists.openstack.org</a><br>
<a href="http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev" target="_blank">http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev</a><br>
<br></blockquote></div>
</div></div><br>_______________________________________________<br>
OpenStack-dev mailing list<br>
<a href="mailto:OpenStack-dev@lists.openstack.org">OpenStack-dev@lists.openstack.org</a><br>
<a href="http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev" target="_blank">http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev</a><br>
<br></blockquote></div><br></div>