On router neutron-e30f310a-29dd-43a2-8bde-dedd103d9db9, what are the configured networks on its ports? Is 172.24.4.194 in any of the router port subnets?

<< On router neutron-e30f310a-29dd-43a2-8bde-dedd103d9db9, what are the configured networks on its ports? Is 172.24.4.194 in any of the router port subnets?

Yes router have the the corresponding subnet attached, sharing output:- 

# ovn-nbctl list logical_router_port
_uuid               : 9bb9c470-826c-4923-9f56-d6204d3ca09e
enabled             : []
external_ids        : {"neutron:network_name"=neutron-a86e2e4b-59f8-444d-9012-9820f13c0353, "neutron:revision_number"="2", "neutron:router_name"="e30f310a-29dd-43a2-8bde-dedd103d9db9", "neutron:subnet_ids"="a124530e-9ff5-4245-bad6-4f2b8cb9d7e8"}
gateway_chassis     : []
ha_chassis_group    : []
ipv6_prefix         : []
ipv6_ra_configs     : {}
mac                 : "fa:16:3e:37:c6:58"
name                : lrp-5b104bcc-c570-4e0d-ae39-b16e1226e95c
networks            : ["192.0.2.1/24"]
options             : {}
peer                : []

_uuid               : 74a5fdec-86b4-4dfe-9dc1-2fc916e63d6f
enabled             : []
external_ids        : {"neutron:network_name"=neutron-718e9b43-6997-44b2-8750-f239e87bb1c8, "neutron:revision_number"="3", "neutron:router_name"="e30f310a-29dd-43a2-8bde-dedd103d9db9", "neutron:subnet_ids"="9afcbd74-a443-41b3-9c1f-52af7c0e1db3"}
gateway_chassis     : []
ha_chassis_group    : []
ipv6_prefix         : []
ipv6_ra_configs     : {address_mode=slaac, mtu="1442", send_periodic="true"}
mac                 : "fa:16:3e:ad:12:a4"
name                : lrp-487a501e-4f70-4dad-bcef-372c51baba17
networks            : ["fd9e:91f4:dd2f::1/64"]
options             : {}
peer                : []

_uuid               : 9e03c3ed-c3cc-44f7-8c59-e4acf055d85d
enabled             : []
external_ids        : {"neutron:network_name"=neutron-718e9b43-6997-44b2-8750-f239e87bb1c8, "neutron:revision_number"="3", "neutron:router_name"="e30f310a-29dd-43a2-8bde-dedd103d9db9", "neutron:subnet_ids"="e630213e-3aec-4f97-b3ca-ceef7312b23e"}
gateway_chassis     : []
ha_chassis_group    : []
ipv6_prefix         : []
ipv6_ra_configs     : {}
mac                 : "fa:16:3e:72:f0:a0"
name                : lrp-6595ab21-3b99-413b-a393-25befbe4d4af
networks            : ["10.0.0.1/26"]
options             : {}
peer                : []

_uuid               : bf48439d-368c-4096-9185-fd229d4ec801
enabled             : []
external_ids        : {"neutron:network_name"=neutron-29f97601-d55b-49c7-a71b-8335844bdd0f, "neutron:revision_number"="7", "neutron:router_name"="e30f310a-29dd-43a2-8bde-dedd103d9db9", "neutron:subnet_ids"="8227997d-452a-45d8-afcd-4361380dde5a fb434b49-ae92-44a8-b6d8-c1bad41f8da8"}
gateway_chassis     : [8dc6c9c1-c621-4183-ba36-267d89356a8c]
ha_chassis_group    : []
ipv6_prefix         : []
ipv6_ra_configs     : {}
mac                 : "fa:16:3e:9b:d7:39"
name                : lrp-b6f80253-c7e4-4779-bc58-fd77198f30d9
networks            : ["172.24.4.156/24", "2001:db8::1/64"]
options             : {}
peer                : []

(In reply to Yatin Karel from comment #0)

> Workaround:-
> # Add the lb to logical_switch also, but this duplicates lb on both router
> and switch, switch is connected to the router already.
> # ovn-nbctl set logical_switch 39bdfd3a-9f22-4ea0-a720-8b35d26e7d36
> load_balancer=dc6461c2-8d55-4d83-8e71-19a687f47b07

This needs investigation but, if determined that the only solution is to also apply the load balancer to the logical switch, then we probably need to open another RFE BZ to investigate if ovn-northd can do this automatically, to simplify the work of the CMS, and without changing behavior for other CMSs (e.g., ovn-k8s) that apply some load balancers only on gateway routers.

In order to run the "pf-floatingip" lb just on the logical router we need to set the "chassis" option for the router (gw router scenario). Doing so the packet is sent to the hv running the router before performing lr_in_dnat stage and ct operation is properly executed. If we run the scenario with a gw-router-port, it is currently mandatory to configure the lb even on the logical switches otherwise lr_in_dnat will not be executed on the hv running the gw-router-port.

Pushed https://review.opendev.org/c/openstack/neutron/+/833620 to add lb also to logical_switches connected to logical router. When ovn will support this natively, this can be reverted in neutron.

upstream patch: https://patchwork.ozlabs.org/project/ovn/patch/f33a595c87d734b3869cf2397047c227654c0030.1652984552.git.lorenzo.bianconi@redhat.com/