[ovirt-users] Cluster compatibility version and major upgrades

[Yaniv Kaul]

On Thu, Mar 2, 2017 at 4:44 PM Yedidyah Bar David <didi at redhat.com> wrote:

> On Tue, Feb 28, 2017 at 10:06 PM, Chris Adams <cma at cmadams.net> wrote:
> > Hello again, still working on my upgrade from 3.5...
> >
> > I'm trying to understand the cluster compatibility version setting and
> > how that applies to major upgrades.  Do I have to always raise the
> > compatibility version when I do a major upgrade?
>
> Not immediately.
>

Right, but then people forget to do it later ;-)
Y.


> Doing this will let you use the new features.
>
> >  In other words, when I
> > upgrade from 3.5 to 3.6, do I need to raise it to 3.6 before I upgrade
> > to 4.0 (and then again raise it 4.0 before upgrading to 4.1)?
>
> Each engine version has a set of supported compatibility levels.
> If you run engine-setup and have a cluster/DC with a too-old level,
> it will refuse to upgrade.
>
> >
> > It looks like the 3.6->4.0 EL6->EL7 migration requires the cluster
> > compatibility level to be at 3.6 (if I'm reading things right).
>
> Indeed.
>
> >
> > It appears that when I upgrade to 3.6, I will have to stop all running
> > VMs to raise the compatibility version (and I found an open bug about
> > whether that's possible with the hosted engine).  It sounds like with
> > 4.0, the VMs can be flagged for compatibility and I can reboot them
> > individually.  I have over 80 VMs, many behind a load balancer (for HA
> > and load sharing), but taking them all down will obviously still
> > interrupt service for a while.
> >
> > Is there a safe way around that?
> >
> > I saw someone mention they partitioned their servers and made a new
> > cluster (with the new version), and migrated VMs from cluster to
> > cluster.  Can I do live migrations in that case?  How do I get the
> > hosted engine from one cluster to another (especially with starting at
> > 3.5)?
>
> You'll definitely need hosted-engine downtime, but that's usually not
> an issue. For your other VMs, not sure - I think that if you get a mark
> saying they should be rebooted, they should. See also:
>
> https://bugzilla.redhat.com/show_bug.cgi?id=1336527
>
> Best,
> --
> Didi
> _______________________________________________
> Users mailing list
> Users at ovirt.org
> http://lists.ovirt.org/mailman/listinfo/users
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ovirt.org/pipermail/users/attachments/20170302/149e4d40/attachment.html>