CentOS: docker fails to start with "no sockets found via socket activation"

[David Moreau Simard]

The kolla-ansible baremetal roles sets up a systemd docker unit override:

https://github.com/openstack/kolla-ansible/blob/49c0ca3a9cc5ba3874aeb7b5fd2215750a1e25bc/ansible/roles/baremetal/tasks/post-install.yml#L11-L17

https://github.com/openstack/kolla-ansible/blob/3e8f9986d1229896af3e52e5a138bcbb7244a449/ansible/roles/baremetal/templates/docker_systemd_service.j2

This is what ends up being set up on my system:
====
# cat /etc/systemd/system/docker.service.d/kolla.conf
[Service]
MountFlags=shared
ExecStart=
ExecStart=/usr/bin/docker daemon \
 -H fd://
====

This yields an error when starting docker:
====
Dec 21 16:21:32 centos-testing systemd[1]: Starting Docker Application Container Engine...
Dec 21 16:21:32 centos-testing docker[13361]: time="2016-12-21T16:21:32.284909995Z" level=fatal msg="no sockets found via socket activation: make sure the service was started by systemd"
Dec 21 16:21:32 centos-testing systemd[1]: docker.service: main process exited, code=exited, status=1/FAILURE
Dec 21 16:21:32 centos-testing systemd[1]: Failed to start Docker Application Container Engine.
Dec 21 16:21:32 centos-testing systemd[1]: Unit docker.service entered failed state.
Dec 21 16:21:32 centos-testing systemd[1]: docker.service failed.
====

In multiple references to this issue, the solution seems to not use "-H fd://", ex:
- https://github.com/docker/docker/issues/11135
- https://github.com/docker/docker/issues/22847
- https://github.com/docker/docker/issues/25098

I've confirmed (manually) that removing it makes Docker work again.

I don't see "-H fd://" mentioned in Kolla documentation, such as here http://docs.openstack.org/developer/kolla/newton/quickstart.html#install-dependencies

Can we take that out of the baremetal role ? CentOS is broken when using the baremetal role right now.

[Jeffrey Zhang (jeffrey4l)]

-H fd:// should be removed.

now in docker-engine rpm package, there is not docker.socket file. and add this parameter will break the docker-engine service.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/413911

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/413911
Committed: https://git.openstack.org/cgit/openstack/kolla-ansible/commit/?id=7b5e5591fe7108117221eacfffe6e7edbd33ddfa
Submitter: Jenkins
Branch: master

commit 7b5e5591fe7108117221eacfffe6e7edbd33ddfa
Author: Jeffrey Zhang <email address hidden>
Date: Thu Dec 22 13:15:28 2016 +0800

    Remove -H fd:// for docker.service in the baremetal role

    Change-Id: I9232c10448773410a9b7cf932f68696d69bd0462
    Closes-Bug: #1651816

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/kolla-ansible 4.0.0.0b3 development milestone.