On 2018-10-24T12:37:50, Sebastian Wagner <swagner@xxxxxxx> wrote:
> >> 3) Delegate this to the new orchestrator. Kube can just run this command
> >> wherever we want. Ansible presumably can too.
> >
> > I agree with Kai and Jan that this is the way to go.
> >
> > Using the libstoragemgmt network service is still possible, it would
> > just be an implementation detail for the orchestrator itself. I can
> > imagine that in some future container environments, deploying
> > something like the libstoragemgmt network service becomes quite
> > cheap/easy, and saves the effort of tools like Rook implementing their
> > own agent hooks -- but Ceph won't care.
> >
> > This would be an area where we need to get the orchestrator's device
> > names in line with Ceph's internal device naming -- that would be
> > useful anyway for other orchestrator functionality.
>
> Yes. As the OSD may no longer be running, and thus out of reach for
> Ceph, we should to use the orchestrator for that.
I feel stupid for agreeing with this yet again, but also exactly because
in a containerized world (where maybe only the specific LV is exposed to
the pod) ceph-osd might not be able to even.
And finally, we may want to be able to blink which disk we are *about to
provision*, or which slot to plug the disk into, so in ceph-volume setup
stages. Anything that relies on the ceph-osd process is a bit flawed.
And the orchestrator has all the access privileges because it needs them
anyway.
> > I'd be inclined to just make the command synchronous, and return an
> > error if the host is unreachable (perhaps with a special force flag to
> > clear out Ceph's state if the host is gone and never coming back).
Actually this should probably be build with the extension to the whole
node in mind! In case of a total node failure in a 500 node DC, this
might need to be blinked just as well.
Regards,
Lars
--
SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
"Architects should open possibilities and not determine everything." (Ueli Zbinden)
