Hi  Jaewook,
I had a similar issue after deploying an AIO Simplex StarlingX.
I had to re-define the host-if on the controller-0 first and then create the related providernet.

Here an example. Hope it helps.

[wrsroot@controller-0 ~(keystone_admin)]$ system host-if-list controller-0
+--------------------------------------+------+----------+----------+------+-----------+------+------+-------------------+-------------------+
| uuid                                 | name | class    | type     | vlan | ports     | uses | used | attributes        | provider networks |
|                                      |      |          |          | id   |           | i/f  | by   |                   |                   |
|                                      |      |          |          |      |           |      | i/f  |                   |                   |
+--------------------------------------+------+----------+----------+------+-----------+------+------+-------------------+-------------------+
| 38da435a-5fc5-44ac-b038-52af9f23d52d | lo   | platform | virtual  | None | []        | []   | []   | MTU=1500          | None              |
| 7f806264-9c19-45f4-b7d7-df1f90e9d540 | eno5 | platform | ethernet | None | [u'eno5'] | []   | []   | MTU=1500          | None              |
| 9f7365e8-bc9a-4c9c-8725-72d40f5a18ff | eno6 | data     | ethernet | None | [u'eno6'] | []   | []   | MTU=1500,         | public_flat       |
|                                      |      |          |          |      |           |      |      | accelerated=True  |                   |
|                                      |      |          |          |      |           |      |      |                   |                   |
+--------------------------------------+------+----------+----------+------+-----------+------+------+-------------------+-------------------+
[wrsroot@controller-0 ~(keystone_admin)]$ openstack providernet list
+--------------------------------------+---------------+------+------+--------+
| ID                                   | Name          | Type |  MTU | Ranges |
+--------------------------------------+---------------+------+------+--------+
| 197c33ba-6db0-4918-9a0e-e98b01aee1e8 | public_flat   | flat | 1500 |        |
+--------------------------------------+---------------+------+------+--------+


Besides, you can't create it via dashboard,. I managed to do it only via command. So something like:

neutron providernet-create public_flat --type=flat
system host-if-list -a controller-0
system host-if-modify -c data controller-0 eno6 -p public_flat 
system host-if-list -a controller-0
openstack network create provider_flat --provider-physical-network public_flat --provider-network-type flat --share --external 

which will create something like:
[wrsroot@controller-0 ~(keystone_admin)]$ openstack network show provider_flat
+---------------------------+--------------------------------------+
| Field                     | Value                                |
+---------------------------+--------------------------------------+
| admin_state_up            | UP                                   |
:
| provider:network_type     | flat                                 |
| provider:physical_network | public_flat                          |
| provider:segmentation_id  | None                                 |
| qos_policy_id             | None                                 |
| revision_number           | 4                                    |
| router:external           | External                             |
:
+---------------------------+--------------------------------------+

/Giuseppe


On Tue, 22 Jan 2019 at 08:47, Jaewook Oh <jwoh95@dcn.ssu.ac.kr> wrote:
Hello Hu, Yong,
Thanks for the advice.

On my dashboard, "Danger: An error occurred. Please try again later." 
Above error message appears, and I cannot open network creation panel.

And also I'm now trying to see log in the host, but I cannot find it. Is the log disabled by default for StarlingX?

BR,
Jaewook.

2019년 1월 22일 (화) 오후 4:08, Hu, Yong <yong.hu@intel.com>님이 작성:

Hey,

Pls share the error messages you saw on Horizon.

 

As to your question: “Is there any way to create flat network on StarlingX openstack platform?”

Yes, you can refer to CMD:

$ openstack help providernet create

$ openstack help network create

 

Of course, since you had error on Horizon, there should be something wrong.

So, let’s figure out why it failed first.

 

From: Jaewook Oh <kyle.oh95@gmail.com>
Date: Tuesday, 22 January 2019 at 2:35 PM
To: "starlingx-discuss@lists.starlingx.io" <starlingx-discuss@lists.starlingx.io>
Subject: [Starlingx-discuss] After deployment finished, cannot create public flat network

 

Hello,

this is Jaewook Oh from IISTRC.

 

I installed StarlingX on a server, and now I'm trying to create "flat network" for public.

However I couldn't find the way to make the network.

I found "managed_flat", "managed_vlan", and "managed_vxlan" options in '/etc/neutron/plugins/ml2/ml2_conf.ini' file.

 

When I install some OpenStack platform, I usually used devstack, and with devstack I could choose 'flat' option.

 

Is there any way to create flat network on StarlingX openstack platform?

 

And also network creation keeps failing on horizon dashboard. I had to use OpenStack CLI. Is it also a bug?

 

Thanks in advance for any help!

 

Best Regards,

Jaewook.

 

================================================
Jaewook Oh (오재욱)
IISTRC - Internet Infra System Technology Research Center
369 Sangdo-ro, Dongjak-gu,
06978, Seoul, Republic of Korea

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Jaewook Oh (오재욱)
IISTRC - Internet Infra System Technology Research Center
369 Sangdo-ro, Dongjak-gu,
06978, Seoul, Republic of Korea
Tel : +82-2-820-0841 | Mobile : +82-10-9924-2618
E-mail : jwoh95@dcn.ssu.ac.kr
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