[Openstack] dhcp request can't reach br-int of network node

Jonathan Proulx jon at jonproulx.com
Fri Feb 7 17:54:38 UTC 2014


It's most likely you need to look inside the namespaces to see the
traffic on br-int, are you familiar with 'ip netns exec'?  I just
added a bit about this to the operators guide
http://docs.openstack.org/trunk/openstack-ops/content/network_troubleshooting.html#dealing_with_netns
there's a bit more above that explaining a flow similar to what you
linked to.

Namespaces can seem like a bit of voodoo that packets disappear into...

-Jon

On Fri, Feb 7, 2014 at 11:41 AM, Chris Baker <openstack2014 at qq.com> wrote:
> Hi guys,
>
> My havana installation has 3 nodes:
> control node, runs keystone APIs and neutron server;
> network node, runs l3, dhcp, metadata, ovs agents; with VLAN mode
> compute node, runs nova compute and ovs agents;
>
> repo from http://repos.fedorapeople.org/repos/openstack/openstack-havana,
> and the os gets updated well with latest kernel.
>
>
> Currently my VM can't get dhcp ack from network node.
> Based the topology picture for the package flow:
> http://docs.openstack.org/admin-guide-cloud/content/figures/10/a/common/figures/under-the-hood-scenario-1-ovs-network.png
>
> With the tcpdump result on both network and compute node, it says the dhcp
> request successfully leaves compute node, and it can reach the "int-br-eth1"
> of network node, but not the next step br "br-int", so the dnsmasq would not
> able to ack. I think this is the problem why I can't get dhcp ipaddr.
>
> # uname -r
> 2.6.32-358.123.2.openstack.el6.x86_64
>
> # ip netns  (should we say namespace works well?)
> qdhcp-11f3adc1-6a2e-429b-9679-b565347e2f74
> qdhcp-4aaa7c19-7864-4b17-aebc-d6aa354d4cd5
> qdhcp-285e259e-e3ec-4149-81db-8e94e1713aa2
> qdhcp-4044cdf0-717b-4628-9ce0-a9ff49533d8f
> qrouter-76c9b884-5928-42f4-a016-afab1b72066b
>
> Anyone can help where/which section I should check for the issue next? or
> let me know if other info is needed.
> Thanks a lot.
>
> Chris
>
> _______________________________________________
> Mailing list: http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack
> Post to     : openstack at lists.openstack.org
> Unsubscribe : http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack
>




More information about the Openstack mailing list