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==============
OVN To-do List
==============

* Refactor ovn-northd code to have separate functions to add logical flows
  for gateway logical routers and logical routers with distributed gateway
  port.

* VLAN trunk ports.

  Russell Bryant: "Today that would require creating 4096 ports for the VM and
  attach to 4096 OVN networks, so doable, but not quite ideal."

* Service function chaining.

* Hitless upgrade, especially for data plane.

* Dynamic IP to MAC binding enhancements.

  OVN has basic support for establishing IP to MAC bindings dynamically, using
  ARP.

  * Table size limiting.

    The table of MAC bindings must not be allowed to grow unreasonably large.

* MTU handling (fragmentation on output)

* Support multiple tunnel encapsulations in Chassis.

  So far, both ovn-controller and ovn-controller-vtep only allow chassis to
  have one tunnel encapsulation entry.  We should extend the implementation
  to support multiple tunnel encapsulations.

* Update learned MAC addresses from VTEP to OVN

  The VTEP gateway stores all MAC addresses learned from its physical
  interfaces in the 'Ucast_Macs_Local' and the 'Mcast_Macs_Local' tables.
  ovn-controller-vtep should be able to update that information back to
  ovn-sb database, so that other chassis know where to send packets destined
  to the extended external network instead of broadcasting.

* Translate ovn-sb Multicast_Group table into VTEP config

  The ovn-controller-vtep daemon should be able to translate the
  Multicast_Group table entry in ovn-sb database into Mcast_Macs_Remote table
  configuration in VTEP database.

* OVN OCF pacemaker script to support Active / Passive HA for OVN dbs provides
  the option to configure the inactivity_probe value. The default 5 seconds
  inactivity_probe value is not sufficient and ovsdb-server drops the client
  IDL connections for openstack deployments when the neutron server is heavily
  loaded.

  We need to find a proper solution to solve this issue instead of increasing
  the inactivity_probe value.

* ACL

  * Support FTP ALGs.

* OVN Interconnection

  * Packaging for Debian.

* IP Multicast Relay

  * When connecting bridged logical switches (localnet) to logical routers
    with IP Multicast Relay enabled packets might get duplicated. We need
    to find a way of determining if routing has already been executed (on a
    different hypervisor) for the IP multicast packet being processed locally
    in the router pipeline.

* ovn-controller Incremental processing

  * Implement I-P for datapath groups.

* ovn-northd parallel logical flow processing

  * Multi-threaded logical flow computation was optimized for the case
    when datapath groups are disabled.  Datpath groups are always enabled
    now so northd parallel processing should be revisited.

* ovn-controller daemon module

  * Dumitru Ceara: Add a new module e.g. ovn/lib/daemon-ovn.c that wraps
    OVS' daemonize_start() call and initializes the additional things, like
    the unixctl commands. Or, we should move the APIs such as
    daemon_started_recently() to OVS's lib/daemon.

* Chassis_Template_Var

  * Support template variables when tracing packets with ovn-trace.

* Load Balancer templates

  * Support combining the VIP IP and port into a single template variable.

* ovn-controller conditional monitoring

  * Improve sub-ports (with parent_port set) conditional monitoring; these
    are currently unconditionally monitored, even if ovn-monitor-all is
    set to false.

* ovn-northd parallel build

  * Move the lflow build parallel processing from northd.c to lflow-mgr.c
    This would also ensure that the variables declared in northd.c
    (eg. thread_lflow_counter) are not externed in lflow-mgr.c.

* Remove OVS database schema parsing from features.c once server side column
  types are available through IDL.
