N-api failed to start when running through devstack

[Alex Rudenko]

I downloaded the latest version of Devstack (checked out via git) and I'm running ./stack.sh

I get the following error:

/opt/stack/horizon$ cd /opt/stack/nova && /usr/local/bin/nova-api || echo "n-api failed to start" | tee "/opt/stack/status/stack/n-api.failure"
Traceback (most recent call last):
  File "/usr/local/bin/nova-api", line 6, in <module>
    from nova.cmd.api import main
  File "/opt/stack/nova/nova/cmd/api.py", line 29, in <module>
    from nova import config
  File "/opt/stack/nova/nova/config.py", line 22, in <module>
    from nova.openstack.common.db.sqlalchemy import session as db_session
  File "/opt/stack/nova/nova/openstack/common/db/sqlalchemy/session.py", line 279, in <module>
    deprecated_opts=[cfg.DeprecatedOpt('sql_connection',
AttributeError: 'module' object has no attribute 'DeprecatedOpt'
n-api failed to start

I'm new to this project, please let me know if you need more details

[Jarek Miszczyk (6-jarek)]

I saw the same behavior on my system. Here's what I did to fix it.

1. Check the content of the /usr/local/lib/python2.7/dist-packages/ directory

2. If you see a directory named oslo novagate to it and the to its subdirectory config. Check the timestamp on the cfg.py file. You will probably see and older timestamp (way before your current stack.sh execution.

3. The clean approach would be to uninstall the packahe:
sudo pip uninstall oslo

If this doesn't work you may try the brute force: (use at your own discretion)

4. Manually remove the oslo directory:
sudo rm -Rf /usr/local/lib/python2.7/dist-packages/ oslo

and the corresponding oslo-config egg and pth files in /usr/local/lib/python2.7/dist-packages/

4. Rerun ./stack.sh

This has fixed the issue on my system.

[Alex Rudenko (alexei-rudenko)]

Thank you, Jarek. Your solution works fine.

So, is it a problem of devstack or of my particular installation?

[melanie witt (melwitt)]

Marking this as invalid because it seems like a devstack issue, if anything?

[Robbie Harwood (rharwood)]

This is working for me. Can you post your devstack configuration?