Hello Misak, 

This error hints that your ovn databases are not up (or at least can not be connected to).
Could you please check if the following command gives any output:

    ps -ef|grep 'ovnsb_db\|ovnnb_db'

The databases can be started (if not active) using:
   /usr/share/openvswitch/scripts/ovn-ctl start_ovsdb

Could you please also check the content of:
  /var/run/openvswitch/

The filenames don't look normal (usually they do not contain any numbers as part of them), please give me some time to check this.

Thanks,
Marcin





On Wed, Dec 27, 2017 at 3:44 PM, Mor Kalfon <mkalfon@redhat.com> wrote:
Hello Misak,

Could you please file a bug about those error messages that you receive from OVS?
You can use the log collector tool (https://www.ovirt.org/documentation/admin-guide/chap-Utilities/#the-log-collector-tool)
which gathers all the required logs for us to investigate this issue.

Thanks for reporting this issue!

On Wed, Dec 27, 2017 at 11:03 AM, Misak Khachatryan <kmisak@gmail.com> wrote:
On Wed, Dec 27, 2017 at 12:42 PM, Dan Kenigsberg <danken@redhat.com> wrote:
> On Wed, Dec 27, 2017 at 8:49 AM, Misak Khachatryan <kmisak@gmail.com> wrote:
>> Hi,
>>
>> It's not on log file, it's from automatic email sent by cron daemon.
>> This one from logrotate.
>
> Would you file a bug about this daily logrotate spam?
>

Sure, will do.

>>
>> I'd like to migrate my network to OVS, but as i can't find any guide
>> for that, it's a bit scary.
>
> Why would you like to do that? OVN is useful for big deployments, that
> have many isolated networks. It is not universally recommended, as it
> uses more CPU.
>

No particular reason, thought that will be future in oVIRT networking,
also i work in relatively big ISP with many PoP and DCs in many
cities. And I'm interested to try it some time.

>>
>> Best regards,
>> Misak Khachatryan
>>
>>
>> On Tue, Dec 26, 2017 at 3:29 PM, Dan Kenigsberg <danken@redhat.com> wrote:
>>> On Tue, Dec 26, 2017 at 8:35 AM, Misak Khachatryan <kmisak@gmail.com> wrote:
>>>> Hi,
>>>>
>>>> After upgrade to 4.2 I started getting this error from engine:
>>>>
>>>> /etc/cron.daily/logrotate:
>>>>
>>>> 2017-12-25T23:12:02Z|00001|unixctl|WARN|failed to connect to
>>>> /var/run/openvswitch/ovnnb_db.19883.ctl
>>>> ovs-appctl: cannot connect to
>>>> "/var/run/openvswitch/ovnnb_db.19883.ctl" (No such file or directory)
>>>> 2017-12-25T23:12:02Z|00001|unixctl|WARN|failed to connect to
>>>> /var/run/openvswitch/ovnsb_db.19891.ctl
>>>> ovs-appctl: cannot connect to
>>>> "/var/run/openvswitch/ovnsb_db.19891.ctl" (No such file or directory)
>>>>
>>>>
>>>> Seems harmless as i don't use OVS, but how to fix it?
>>>
>>> By default, ovirt-4.2 installs and configure OVN (which uses OVS). You
>>> can turn it off on Engine host by running
>>> systemctl stop ovirt-provider-ovn ovn-northd openvswitch
>
> did you try that?
>

No, but is correct way to disable it completely?

>>>
>>> but I'd appreciate your help to understand in which log file do you
>>> see these warnings?
>
>>> Have you already disabled openvswitch?
>
> have you ^^ ?

No, what is a correct way to do it?



--
Mor Kalfon
RHV Networking Team
Red Hat IL-Raanana