Comment 24 for bug 1833835

Reviewed: https://review.opendev.org/674587
Committed: https://git.openstack.org/cgit/openstack/kolla-ansible/commit/?id=35941738d59002f8bbf55d25b3468619983dcea6
Submitter: Zuul
Branch: master

commit 35941738d59002f8bbf55d25b3468619983dcea6
Author: Marcin Juszkiewicz <email address hidden>
Date: Mon Aug 5 14:18:06 2019 +0200

    Stop using MountFlags=shared in Docker configuration

    According to Docker upstream release notes [1] MountFlags should be
    empty.

    1. https://docs.docker.com/engine/release-notes/#18091

    "Important notes about this release

    In Docker versions prior to 18.09, containerd was managed by the Docker
    engine daemon. In Docker Engine 18.09, containerd is managed by systemd.
    Since containerd is managed by systemd, any custom configuration to the
    docker.service systemd configuration which changes mount settings (for
    example, MountFlags=slave) breaks interactions between the Docker Engine
    daemon and containerd, and you will not be able to start containers.

    Run the following command to get the current value of the MountFlags
    property for the docker.service:

    sudo systemctl show --property=MountFlags docker.service
    MountFlags=

    Update your configuration if this command prints a non-empty value for
    MountFlags, and restart the docker service."

    Closes-bug: #1833835

    Change-Id: I4f4cbb09df752d00073a606463c62f0a6ca6c067