Comment 10 for bug 1777123

It seems, that the problem lies not in the openstack-ansible, but rather in ceph repos.

OSA installs python-ceph package from ceph repo here:
https://github.com/openstack/openstack-ansible-ceph_client/blob/e67c08ca99e2f951d517af8e0735a90177f2e3ab/vars/ubuntu.yml#L43

python-ceph has python-rbd in its dependencies, and python-rbd provides rbd library, which is symlinked into virtualenv. However, deb package python-rbd of version 12.2.7 has python rbd library of version 2.0:

root@nova01:~# dpkg -l | grep python-rbd
ii python-rbd 12.2.7-1xenial amd64 Python 2 libraries for the Ceph librbd library
root@nova01:~# dpkg-query -L python-rbd
/.
/usr
/usr/share
/usr/share/doc
/usr/share/doc/python-rbd
/usr/share/doc/python-rbd/copyright
/usr/share/doc/python-rbd/changelog.Debian.gz
/usr/lib
/usr/lib/python2.7
/usr/lib/python2.7/dist-packages
/usr/lib/python2.7/dist-packages/rbd.x86_64-linux-gnu.so
/usr/lib/python2.7/dist-packages/rbd-2.0.0.egg-info
/usr/lib/python2.7/dist-packages/rbd-2.0.0.egg-info/dependency_links.txt
/usr/lib/python2.7/dist-packages/rbd-2.0.0.egg-info/top_level.txt
/usr/lib/python2.7/dist-packages/rbd-2.0.0.egg-info/PKG-INFO
root@nova01:~# apt show python-rbd
Package: python-rbd
Version: 12.2.7-1xenial
Priority: optional
Section: python
Source: ceph
Maintainer: Ceph Maintainers <email address hidden>
Installed-Size: 461 kB
Depends: librbd1 (>= 12.2.7-1xenial), python (<< 2.8), python (>= 2.7~), libc6 (>= 2.4), libpython2.7 (>= 2.7)
Breaks: python-ceph (<< 0.92-1223)
Replaces: python-ceph (<< 0.92-1223)
Homepage: http://ceph.com/
Download-Size: 127 kB
APT-Manual-Installed: no
APT-Sources: http://download.ceph.com/debian-luminous xenial/main amd64 Packages
Description: Python 2 libraries for the Ceph librbd library
 Ceph is a massively scalable, open-source, distributed
 storage system that runs on commodity hardware and delivers object,
 block and file system storage.
 .
 This package contains Python 2 libraries for interacting with Ceph's
 RBD block device library.

N: There are 3 additional records. Please use the '-a' switch to see them.
root@uacloud-nova01:~#

So it seems, that this bug has almost nothing to do with OSA. And it seems, that everyone, who will install rbd library not from pip (or sources) will face with this bug...