[openstack-dev] Introducing the new OpenStack service for Containers

Rick Harris rconradharris at gmail.com
Thu Nov 21 17:03:25 UTC 2013


++ on Fri. 9am PST.


On Thu, Nov 21, 2013 at 10:57 AM, Sam Alba <sam.alba at gmail.com> wrote:

> I wish we can make a decision during this meeting. Is it confirmed for
> Friday 9am pacific?
>
> On Thu, Nov 21, 2013 at 8:24 AM, Chuck Short <chuck.short at canonical.com>
> wrote:
> > Hi
> >
> > Has a decision happened when this meeting is going to take place,
> assuming
> > it is still taking place tomorrow.
> >
> > Regards
> > chuck
> >
> >
> > On Mon, Nov 18, 2013 at 7:58 PM, Krishna Raman <kraman at gmail.com> wrote:
> >>
> >>
> >> On Nov 18, 2013, at 4:30 PM, Russell Bryant <rbryant at redhat.com> wrote:
> >>
> >> On 11/18/2013 06:30 PM, Dan Smith wrote:
> >>
> >> Not having been at the summit (maybe the next one), could somebody
> >> give a really short explanation as to why it needs to be a separate
> >> service? It sounds like it should fit within the Nova area. It is,
> >> after all, just another hypervisor type, or so it seems.
> >>
> >>
> >> But it's not just another hypervisor. If all you want from your
> >> containers is lightweight VMs, then nova is a reasonable place to put
> >> that (and it's there right now). If, however, you want to expose the
> >> complex and flexible attributes of a container, such as being able to
> >> overlap filesystems, have fine-grained control over what is shared with
> >> the host OS, look at the processes within a container, etc, then nova
> >> ends up needing quite a bit of change to support that.
> >>
> >> I think the overwhelming majority of folks in the room, after discussing
> >> it, agreed that Nova is infrastructure and containers is more of a
> >> platform thing. Making it a separate service lets us define a mechanism
> >> to manage these that makes much more sense than treating them like VMs.
> >> Using Nova to deploy VMs that run this service is the right approach,
> >> IMHO. Clayton put it very well, I think:
> >>
> >>  If the thing you want to deploy has a kernel, then you need Nova. If
> >>  your thing runs on a kernel, you want $new_service_name.
> >>
> >> I agree.
> >>
> >> Note that this is just another service under the compute project (or
> >> program, or whatever the correct terminology is this week).
> >>
> >>
> >> The Compute program is correct.  That is established terminology as
> >> defined by the TC in the last cycle.
> >>
> >> So while
> >> distinct from Nova in terms of code, development should be tightly
> >> integrated until (and if at some point) it doesn't make sense.
> >>
> >>
> >> And it may share a whole bunch of the code.
> >>
> >> Another way to put this:  The API requirements people have for
> >> containers include a number of features considered outside of the
> >> current scope of Nova (short version: Nova's scope stops before going
> >> *inside* the servers it creates, except file injection, which we plan to
> >> remove anyway).  That presents a problem.  A new service is one possible
> >> solution.
> >>
> >> My view of the outcome of the session was not "it *will* be a new
> >> service".  Instead, it was, "we *think* it should be a new service, but
> >> let's do some more investigation to decide for sure".
> >>
> >> The action item from the session was to go off and come up with a
> >> proposal for what a new service would look like.  In particular, we
> >> needed a proposal for what the API would look like.  With that in hand,
> >> we need to come back and ask the question again of whether a new service
> >> is the right answer.
> >>
> >> I see 3 possible solutions here:
> >>
> >> 1) Expand the scope of Nova to include all of the things people want to
> >> be able to do with containers.
> >>
> >> This is my least favorite option.  Nova is already really big.  We've
> >> worked to split things out (Networking, Block Storage, Images) to keep
> >> it under control.  I don't think a significant increase in scope is a
> >> smart move for Nova's future.
> >>
> >> 2) Declare containers as explicitly out of scope and start a new project
> >> with its own API.
> >>
> >> That is what is being proposed here.
> >>
> >> 3) Some middle ground that is a variation of #2.  Consider Ironic.  The
> >> idea is that Nova's API will still be used for basic provisioning, which
> >> Nova will implement by talking to Ironic.  However, there are a lot of
> >> baremetal management things that don't fit in Nova at all, and those
> >> only exist in Ironic's API.
> >>
> >> I wanted to mention this option for completeness, but I don't actually
> >> think it's the right choice here.  With Ironic you have a physical
> >> resource (managed by Ironic), and then instances of an image running on
> >> these physical resources (managed by Nova).
> >>
> >> With containers, there's a similar line.  You have instances of
> >> containers (managed either by Nova or the new service) running on
> >> servers (managed by Nova).  I think there is a good line for separating
> >> concerns, with a container service on top of Nova.
> >>
> >>
> >> Let's ask ourselves:  How much overlap is there between the current
> >> compute API and a proposed containers API?  Effectively, what's the
> >> diff?  How much do we expect this diff to change in the coming years?
> >>
> >> The current diff demonstrates a significant clash with the current scope
> >> of Nova.  I also expect a lot of innovation around containers in the
> >> next few years, which will result in wanting to do new cool things in
> >> the API.  I feel that all of this justifies a new API service to best
> >> position ourselves for the long term.
> >>
> >>
> >> +1
> >>
> >> We need to come up with the API first before we decide if this is a new
> >> service or just something that
> >> needs to be added to Nova,
> >>
> >> How about we have all interested parties meet on IRC or conf. call and
> >> discuss the suggested REST API,
> >> open questions and architecture.
> >>
> >> If you are interested please add your name to the participant list on
> >> https://etherpad.openstack.org/p/containers-service.
> >>
> >> I have also set up a doodle poll at http://doodle.com/w7y5qcdvq9i36757to
> >> gather a times when a majority
> >> of us are available to discuss on IRC.
> >>
> >> --
> >> Krishna Raman
> >>
> >> PS: Sorry if you see this email twice. I am having some issues with list
> >> subscription.
> >>
> >>
> >> --
> >> Russell Bryant
> >>
> >> _______________________________________________
> >> OpenStack-dev mailing list
> >> OpenStack-dev at lists.openstack.org
> >> http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
> >>
> >>
> >>
> >> _______________________________________________
> >> OpenStack-dev mailing list
> >> OpenStack-dev at lists.openstack.org
> >> http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
> >>
> >
> >
> > _______________________________________________
> > OpenStack-dev mailing list
> > OpenStack-dev at lists.openstack.org
> > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
> >
>
>
>
> --
> @sam_alba
>
> _______________________________________________
> OpenStack-dev mailing list
> OpenStack-dev at lists.openstack.org
> http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstack.org/pipermail/openstack-dev/attachments/20131121/0b147c21/attachment.html>


More information about the OpenStack-dev mailing list