[ovs-dev] [PATCH v3] OVN: Add support for Transport Zones

[Lucas Alvares Gomes]

On Sat, Apr 13, 2019 at 12:08 AM Ben Pfaff <blp at ovn.org> wrote:
>
> On Thu, Mar 28, 2019 at 10:37:00AM +0000, lmartins at redhat.com wrote:
> > From: Lucas Alvares Gomes <lucasagomes at gmail.com>
> >
> > This patch is adding support for Transport Zones. Transport zones (a.k.a
> > TZs) is way to enable users of OVN to separate Chassis into different
> > logical groups that will form tunnels only between members of the same
> > group(s).
>
> Thanks for working on this.
>
> This adds a new property to a Chassis and implements that property
> through the Chassis record's external-ids.  This strikes me as a
> layering violation, because external-ids is usually reserved for higher
> layers in the system.  Its documentation says:
>
>               external_ids: map of string-string pairs
>                      Key-value  pairs for use by the software that manages the
>                      OVN  Southbound  database   rather   than   by   ovn-con‐
>                      troller/ovn-controller-vtep.  In  particular,  ovn-northd
>                      can use key-value pairs in this column to relate entities
>                      in the southbound database to higher-level entities (such
>                      as entities in the OVN Northbound  database).  Individual
>                      key-value  pairs in this column may be documented in some
>                      cases to aid in understanding  and  troubleshooting,  but
>                      the  reader should not mistake such documentation as com‐
>                      prehensive.
>
> It would be a more natural fit to add a transport_zones column to the
> Chassis table.  (Probably a "set of strings" instead of a
> comma-delimited string.)
>

Good point, yeah by the description of that column it sounds like my
patch is misusing it indeed. I will modify the patch with your
suggestion.

I will also make sure we are good with upgrades because the upgrade
guide [0] recommends upgrading the ovn-controller service before the
OVSDBs so, I should handle the case where this new column does not yet
exist in the database as well.

[0] http://docs.openvswitch.org/en/latest/intro/install/ovn-upgrades/

> The new property should be documented in ovn-sb.xml.
>

Will do!

Thanks,
Lucas