[Bug 1192848] New: docker no longer supports socket-activation

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1192848

Bug ID: 1192848
           Summary: docker no longer supports socket-activation
           Product: Fedora
           Version: 21
         Component: docker-io
          Assignee: [e-mail]
          Reporter: [e-mail]
        QA Contact: [e-mail]
                CC: [e-mail], [e-mail],
                    [e-mail], [e-mail],
                    [e-mail], [e-mail],
                    [e-mail], [e-mail],
                    [e-mail], [e-mail], [e-mail],
                    [e-mail], [e-mail]

Version-Release number of selected component (if applicable):
docker-io-1.4.1-8.fc21.x86_64

How reproducible:
Always

Steps to Reproduce:

$ docker ps

Actual results:

FATA[0000] Cannot connect to the Docker daemon. Is 'docker -d' running on this
host?

Expected results:

/var/run/docker.sock should automatically start `docker.service` via socket
activation. This was the case on fedora 20.

Additional info:

I looked in the package history, and it looks like it was disabled by:

commit aecb9bfe55824e2c9c7be4afce3ac8dd7e3395f5
Author: Lokesh Mandvekar 
Date:   Fri Jan 16 17:06:40 2015 +0000

docker group and socket activation not used

NVR: docker-io-1.4.1-7

- sysconfig file updates

Signed-off-by: Lokesh Mandvekar

I assume there's a reason for this, but there's no bugzilla or other issue
reference, and no description of why the functionality should be removed. The
removal of socket activation is pretty annoying, so it would be great if it
could be re-enabled. If it can't be enabled, it would be good to document why.

[Bug 1192848] docker no longer supports socket-activation

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1192848

Daniel Walsh  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
                 CC|                            |[e-mail]

[Bug 1192848] docker no longer supports socket-activation

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1192848

Fedora Admin XMLRPC Client  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|[e-mail]             |[e-mail]

--- Comment #2 from Fedora Admin XMLRPC Client  ---
This package has changed ownership in the Fedora Package Database.  Reassigning
to the new owner of this component.

[Bug 1192848] docker no longer supports socket-activation

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1192848

Daniel Walsh  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |[e-mail],
                   |                            |[e-mail]
          Component|docker-io                   |docker
            Version|21                          |22
           Assignee|[e-mail]         |[e-mail]

[Bug 1192848] docker no longer supports socket-activation

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1192848

Daniel Walsh  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|unspecified                 |medium

[Bug 1192848] docker no longer supports socket-activation

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1192848

--- Comment #3 from Lokesh Mandvekar  ---
Sorry about the late reply, socket-activation was removed mainly because of
https://github.com/docker/docker/pull/10144#issuecomment-70315230 .
Regarding docker not starting, please make sure your /etc/sysconfig/docker does
_not_ have '-H fd://' included in $OPTIONS. Once, that's done restart the
daemon and everything should work fine. HTH.

[Bug 1192848] docker no longer supports socket-activation

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1192848

--- Comment #4 from Tim Cuthbertson  ---
Thanks for the response, it's good to know the reason behind its removal.
> Regarding docker not starting, please make sure your /etc/sysconfig/docker does _not_ have '-H fd://' included in $OPTIONS. Once, that's done restart the daemon and everything should work fine.

I'm not sure what you're addressing here. Docker starts if I start the service
explicitly (or I assume if I enabled it via multi-user.wants.d or something,
but I don't want to do that because I use docker very rarely). Is this advice
just in case `systemctl start docker.service` fails? (either way, that option
is already not in my config; I haven't changed the system defaults).

[Bug 1192848] docker no longer supports socket-activation

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1192848

--- Comment #5 from Daniel Walsh  ---
docker socket activation breaks the ability for docker to start services
automatically.  Since docker mimics some of the functionality of systemd, users
setting a container to start automatically when the machine reboots would not
work with docker starting on socket activation, since  no process would be
connecting to the /run/docker.sock to trigger docker to start and start its
autostarting containers.

If you don't have these types of containers you should be able to configure
docker to autostart, but we don't want this by default.

[Bug 1192848] docker no longer supports socket-activation

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1192848

Daniel Walsh  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|[e-mail]           |[e-mail]

[Bug 1192848] docker no longer supports socket-activation

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1192848

Daniel Walsh  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |CLOSED
         Resolution|---                         |NOTABUG
           Assignee|[e-mail]            |[e-mail]
        Last Closed|                            |2015-06-02 16:52:55

--- Comment #6 from Daniel Walsh  ---
If we want to get

[Bug 1192848] docker no longer supports socket-activation

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1192848

Martin Sivák  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|CLOSED                      |ASSIGNED
         Resolution|NOTABUG                     |---
           Keywords|                            |Reopened

--- Comment #7 from Martin Sivák  ---
There is one use case you are missing here. A docker.service configured to
autostart via systemd while making sure the docker.socket is in place early.

This is needed for containers that mount /var/run/docker.sock and use it to
discover other running containers. See for example docker-gen or its usage in
https://github.com/jwilder/nginx-proxy

Docker has the annoying habit of creating /var/run/docker.sock/ directory when
mounting the socket before it is created as it assumes a new host directory is
to be mounted as a volume. This can prevent docker service from starting when
combined with autostart containers. It is also almost impossible to fix as
docker tools do not work (no daemon is running) and the daemon can't be started
(because the directory is created during container autostart = before the
proper socket device).

Socket activation (pre-allocation) solves this nicely as the socket file is
already present during the container autostart.

[Bug 1192848] docker no longer supports socket-activation

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1192848

--- Comment #8 from Daniel Walsh  ---
Are you saying docker creates/starts containers before listening on
/var/run/docker.socket?  If yes, then this is the bug.

[Bug 1192848] docker no longer supports socket-activation

[Red Hat Bugzilla]

https://bugzilla.redhat.com/show_bug.cgi?id=1192848

Daniel Walsh  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |CLOSED
         Resolution|---                         |INSUFFICIENT_DATA
        Last Closed|2015-06-02 16:52:55         |2016-06-03 08:38:19