[solved in Py3.7] Rocky openstackclient: issubclass() arg 1 must be a class

asked 2018-12-09 14:29:13 -0500

tjoen gravatar image

updated 2018-12-18 13:48:03 -0500

Last step verify installation
$ openstack network agent list
and first step creating instance
$ openstack network create --share --external --provider-physical-network provider --provider-network-type flat provider
Are giving error: issubclass() arg 1 must be a class
openstackclient doesn't have the string "issubclass" only these dependenciies:
Which one is causing the problem and how to solve it?

edit retag flag offensive close merge delete


You are running into an incompatibility. Perhaps you can find out which module is incompatible by looking at the requirements file, but I would rather deploy it in a venv instead.

Bernd Bausch gravatar imageBernd Bausch ( 2018-12-09 19:29:47 -0500 )edit

Googling for openstack client venv, I found https://help.dreamhost.com/hc/en-us/a....

Bernd Bausch gravatar imageBernd Bausch ( 2018-12-09 19:32:05 -0500 )edit

I think if you run the command with the --debug flag (i.e. openstack --debug network create ...) then it should show you the stack trace that will reveal where the problem is.

zaneb gravatar imagezaneb ( 2018-12-12 19:51:25 -0500 )edit

Somehow the command $ openstack network create ... creates the network, only last display gives the error. I'll try an easier command giving the same error:
$ openstack network agent list
uotput in Answer section below

tjoen gravatar imagetjoen ( 2018-12-13 08:05:25 -0500 )edit

1 answer

Sort by » oldest newest most voted

answered 2018-12-10 02:55:17 -0500

tjoen gravatar image

updated 2018-12-18 13:47:41 -0500

solved by osc-lib patch from https://git.openstack.org/cgit/openst...
I guess problem occurs only in Py3.7

edit flag offensive delete link more


With a venv, you create a set of Python libraries isolated from all the other Python code on your system. You can be certain that the openstack client doesn’t interfere with the rest and vice versa. It very easy to use and takes little time to try it (except the time to learn, but again it’s easy).

Bernd Bausch gravatar imageBernd Bausch ( 2018-12-10 05:37:02 -0500 )edit

OK Thanks! I'll try it and report back

tjoen gravatar imagetjoen ( 2018-12-10 05:43:22 -0500 )edit

There was a problem that pip downloaded idna-2.8 while requests requires idna < 2.8
building netifaces error: command 'gcc' failed with exit status 1 but somehow the cython is there
(venv) ~ $ openstack network agent list
issubclass() arg 1 must be a class

tjoen gravatar imagetjoen ( 2018-12-10 09:00:37 -0500 )edit

(venv) ~ 0$ openstack network create --share --external > --provider-physical-network provider --provider-network-type flat provider
Doesn't give that error. Only another error I need to solve now. But first I'll compare the software versions

tjoen gravatar imagetjoen ( 2018-12-10 09:22:26 -0500 )edit

Newer versions then mine: certifi 2018.11.29 cliff 2.14.0 colorama 0.4.1 cryptography 2.4.2 os-service-types 1.4.0 oslo.i18n 3.23.0 requests 2.20.1 I'll test if upgrading cliff (2.14.0 is Stein) is the sollution

tjoen gravatar imagetjoen ( 2018-12-10 09:43:22 -0500 )edit

Get to know Ask OpenStack

Resources for moderators

Question Tools

1 follower


Asked: 2018-12-09 10:06:57 -0500

Seen: 557 times

Last updated: Dec 18 '18