[ovs-discuss] Troubleshooting network issues with ovn without network namespaces

Vikrant Aggarwal ervikrant06 at gmail.com
Thu Sep 21 08:11:28 UTC 2017


Thanks guys for inputs. Yes, in latest version I can see the network
namespaces.

~~~
root at testuser-KVM:~/devstack# ovs-appctl --version
ovs-appctl (Open vSwitch) 2.8.90

stack at testuser-KVM:~/devstack$ ip netns list
ovnmeta-63691087-3e00-41af-9a77-914cd86b47b5 (id: 0)
~~~

Thanks & Regards,
Vikrant Aggarwal


On Tue, Sep 19, 2017 at 1:46 PM, Daniel Alvarez Sanchez <dalvarez at redhat.com
> wrote:

> Hi Vikrant,
>
> Please note that you won't see the metadata namespace getting created
> right after creating a network. The namespace will be present only when
> necessary; ie., when a port is bound to a chassis and then the metadata
> agent
> will detect that condition and create/provision the metadata namespace
> accordingly *in that chassis*.
>
> So for you to be able to use this namespace for debugging, you would need
> a VM running on that node (or bind a port manually to it through the
> iface-id
> external_id).
>
> Cheers,
> Daniel
>
>
>
> On Tue, Sep 19, 2017 at 10:06 AM, Numan Siddique <nusiddiq at redhat.com>
> wrote:
>
>>
>> Hi Vikrant,
>>
>> Please see this link - https://gist.github.com/russ
>> ellb/4ab0a9641f12f8ac66fdd6822ee7789e  and grep for "add_phys_port".
>>
>> Can you see what is the value of "ovn_metadata_enabled" in the file
>>  /etc/neutron/plugins/ml2/ml2_conf.ini.
>> If it is false, then please change it to true and restart the
>> neutron-server. When you create a new network, you should see a metadata
>> namespace getting created.
>>
>>
>> Thanks
>> Numan
>>
>>
>> On Tue, Sep 19, 2017 at 9:32 AM, Vikrant Aggarwal <ervikrant06 at gmail.com>
>> wrote:
>>
>>> Thanks for your reply Russell.
>>>
>>> I installed devstack with latest development releases but I don't see
>>> the namespace created with latest version also.
>>>
>>> ~~~
>>>
>>> [stack at devstack-centos-controller devstack]$ grep -i ovn local.conf  |
>>> grep -v "#"
>>> enable_plugin networking-ovn https://git.openstack.org/open
>>> stack/networking-ovn
>>> enable_service ovn-northd
>>> enable_service ovn-controller
>>> enable_service networking-ovn-metadata-agent
>>>
>>> [stack at devstack-centos-controller devstack]$ neutron net-list
>>> neutron CLI is deprecated and will be removed in the future. Use
>>> openstack CLI instead.
>>> +--------------------------------------+-----------+--------
>>> --------------------------------------------------+
>>> | id                                   | name      |
>>> subnets                                                  |
>>> +--------------------------------------+-----------+--------
>>> --------------------------------------------------+
>>> | 786530e0-775b-482c-8149-c6e751c188da | internal1 |
>>> dc4961f7-0be3-46be-a545-da7e3a9add8c 10.10.10.0/24       |
>>> | 823cab04-68ea-4d02-843d-ab420e2b0709 | private   |
>>> 00893897-44b3-42e6-9b2d-568568fae221 fde5:d829:f076::/64 |
>>> |                                      |           |
>>> 10b1f798-729c-4329-ae0a-65946fee80e4 10.0.0.0/26         |
>>> | e1ddda3d-eab5-46a9-a880-15f4eab0360c | public    |
>>> b785fc74-ee29-4d0d-bd1f-234337528024                     |
>>> |                                      |           |
>>> d49dc742-9709-4e3b-8a45-68333b7af8b1                     |
>>> +--------------------------------------+-----------+--------
>>> --------------------------------------------------+
>>>
>>> [stack at devstack-centos-controller devstack]$ ip netns list
>>> [stack at devstack-centos-controller devstack]$
>>> ~~~
>>>
>>> Can you please share the steps if you have them handy.
>>>
>>> Thanks & Regards,
>>> Vikrant Aggarwal
>>>
>>>
>>> On Tue, Sep 19, 2017 at 1:51 AM, Russell Bryant <russell at ovn.org> wrote:
>>>
>>>> On Fri, Sep 15, 2017 at 12:45 AM, Vikrant Aggarwal
>>>> <ervikrant06 at gmail.com> wrote:
>>>> > Hi Folks,
>>>> >
>>>> > With ovs as mechanism driver in neutron, I used network namespaces
>>>> often to
>>>> > troubleshoot the network related issue especially with instances
>>>> which are
>>>> > not having floating ip attached to them. It's easy to take ssh
>>>> session to
>>>> > instances without floating ip from network namespace and then take the
>>>> > tcpdump at various hops to troubleshoot the issue.
>>>> >
>>>> > With ovn, hops are reduced as all decisions are made using openflows
>>>> but
>>>> > it's difficult to troubleshoot the issue.
>>>> >
>>>> > Do we have any mechanism to take the ssh session to instance with only
>>>> > private ip in case of ovn and take tcpdump on logical switches and
>>>> ports?
>>>>
>>>> If you're using the latest Neutron integration (networking-ovn), we
>>>> now create namespaces for OpenStack metadata API integration.  You can
>>>> use those namespaces like you did before.
>>>>
>>>> The other option would be to manually create a Neutron port, and then
>>>> manually create an interface in a namespace for that Neutron port.  I
>>>> can send instructions if needed ...
>>>>
>>>> --
>>>> Russell Bryant
>>>>
>>>
>>>
>>> _______________________________________________
>>> discuss mailing list
>>> discuss at openvswitch.org
>>> https://mail.openvswitch.org/mailman/listinfo/ovs-discuss
>>>
>>>
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.openvswitch.org/pipermail/ovs-discuss/attachments/20170921/c111ec9d/attachment.html>


More information about the discuss mailing list