--- issues: - | In OVN 22.09 the option "localnet_learn_fdb" was added, enabling localnet ports to learn MAC addresses and store them at the FDB table. There is no aging mechanism for those MACs (that is the reason for not having this option enabled by default) and therefore it needs to be used with care, specially when provider networks are big. It is recommended to perform periodic manual cleanups of FDB table, to avoid scalability issues -- until OVN implements an aging mechanism for this, tracked at https://bugzilla.redhat.com/show_bug.cgi?id=2179942. fixes: - | By default localnet ports don't learn MAC addresses and therefore they are not stored in the FDB table at OVN SB DB. This leads to flooding issues when the destination traffic is an unknown IP by OpenStack. In OVN 22.09 the option "localnet_learn_fdb" was added, enabling those ports to learn MAC addresses and store them at the FDB table. Note there is no aging mechanism for those MACs, thus this is not enabled by default and needs to be used carefully, specially when provider networks are big, and/or performing manual cleanup of FDB table over time to avoid scalability issues, until OVN implements it at https://bugzilla.redhat.com/show_bug.cgi?id=2179942.