8:04 p.m.
On 28/12, Benny Zlotnik wrote:
On Tue, Dec 22, 2020 at 6:33 PM Konstantin Shalygin
<k0ste(a)k0ste.ru> wrote:
>
> Sandro, FYI we are not against cinderlib integration, more than we are upgrade 4.3
to 4.4 due movement to cinderlib.
>
> But (!) current Managed Storage Block realization support only krbd (kernel RBD)
driver - it's also not a option, because kernel client is always lagging behind
librbd, and every update\bugfix we should reboot whole host instead simple migration of
all VMs and then migrate it back. Also with krbd host will be use kernel page cache, and
will not be unmounted if VM will crash (qemu with librbd is one userland process).
>
There was rbd-nbd support at some point in cinderlib[1] which
addresses your concerns, but it was removed because of some issues
+Gorka, are there any plans to pick it up again?
[1] https://github.com/Akrog/cinderlib/commit/a09a7e12fe685d747ed390a59cd42d0...
Hi,
Apologies for the delay on the response, I was on a long PTO and came
back just yesterday.
There are plans to add it now. ;-)
I will add the RBD-NBD support to cinderlib and update this thread once
there's an RDO RPM available (which usually happens on the same day the
patch merges).
If using QEMU to directly connect RBD volumes is the preferred option,
then that code would have to be added to oVirt and can be done now
without any cinderlib changes. The connection information is provided
by cinderlib, and oVirt can check the type of connection that is is and
do the connection directly in QEMU for RBD volumes, or call os-brick for
all other types of volumes to get a local device before adding it to the
instances.
Cheers,
Gorka.
> So for me current situation look like this:
>
> 1. We update deprecated OpenStack code? Why, Its for delete?.. Nevermind, just
update this code...
>
> 2. Hmm... auth tests doesn't work, to pass test just disable any OpenStack
project_id related things... and... Done...
>
> 3. I don't care how current cinder + qemu code works, just write new one for
linux kernel, it's optimal to use userland apps, just add wrappers (no, it's
not);
>
> 4. Current Cinder integration require zero configuration on oVirt hosts. It's
lazy, why oVirt administrator do nothing? just write manual how-to install packages -
oVirt administrators love anything except "reinstall" from engine (no, it's
not);
>
> 5. We broke old code. New features is "Cinderlib is a Technology Preview
feature only. Technology Preview features are not supported with Red Hat production
service level agreements (SLAs), might not be functionally complete, and Red Hat does not
recommend to use them for production".
>
> 6. Oh, we broke old code. Let's deprecate them and close PRODUCTION issues (we
didn't see anything).
>
>
> And again, we are not hate new cinderlib integration. We just want that new
technology don't break all PRODUCTION clustes. Almost two years ago I write on this
issue https://bugzilla.redhat.com/show_bug.cgi?id=1539837#c6 about "before deprecate,
let's help to migrate". For now I see that oVirt totally will disable QEMU RBD
support and want to use kernel RBD module + python os-brick + userland mappers + shell
wrappers.
>
>
> Thanks, I hope I am writing this for a reason and it will help build bridges between
the community and the developers. We have been with oVirt for almost 10 years and now it
is a crossroads towards a different virtualization manager.
>
> k
>
>
> So I see only regressions for now, hope we'll found some code owner who can
catch this oVirt 4.4 only bugs.
>
I looked at the bugs and I see you've already identified the problem
and have patches attached, if you can submit the patches and verify
them perhaps we can merge the fixes