Comment 6 for bug 1783978

Hello all. Just wanted to update you on some further investigation I did on this. So, the problem isn't the shared bind mount used by the backends mentioned above. It's the nested bind mount! There's /var/lib/nova as a destination of a bind mount on the nova containers and with the above cinder backends /var/lib/nova/mnt is also added as a separate bind mount. This causes the mounts to be doubled every time the nova containers (compute, libvirt, ssh) are restarted.

A solution I've found to this is to change the directory that nova mounts the cinder volumes, by changing quobyte_mount_point_base or nfs_mount_point_base depending on the backend. This also needs that directory to be configured as a new bind mount in the three nova containers in kolla-ansible/ansible/roles/nova/defaults/main.yml. A reconfigure after this and it's all working fine. Then you can just umount the old stale mounts on the host.

I'll be looking to patch this by adding the above login in the nova defaults file if we have nfs or quobyte enabled.

Hope this helps anyone that is facing the mounts problem!