Reviewed: https://review.opendev.org/c/openstack/neutron/+/816856 Committed: https://opendev.org/openstack/neutron/commit/c8427c82dae38154df70400f7d2fe69f0d6c3354 Submitter: "Zuul (22348)" Branch: master
commit c8427c82dae38154df70400f7d2fe69f0d6c3354 Author: Rodolfo Alonso Hernandez <[email protected]> Date: Fri Nov 5 14:56:15 2021 +0000 [OVN] Check new added segments in OVN mech driver Check new segments added to OVN mechanism driver. This mechanism driver does not inherit from ``SimpleAgentMechanismDriverBase`` because OVN has no agents (NOTE 1). However OVN mechanism driver requires an OVN controller service in each deployed chassis. This is how OVN driver knows the hosts using this backend. The segments, attached to an external network (connected to a physical network), can be mapped to a host if ther is a chassis (OVN controller agent) in this host. NOTE 1: OVN provides agent API compatibility, presenting the controller and the metadata services as agents. But OVN mechanism driver has no control or provides any information (via RPC) to those services. Closes-Bug: #1949967 Change-Id: I570b2251da8a4a25d155ba838346b24afafd727f ** Changed in: neutron Status: In Progress => Fix Released -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to neutron. https://bugs.launchpad.net/bugs/1949967 Title: [OVN] OVN mech driver does not map new segments Status in neutron: Fix Released Bug description: Related LP bug: https://bugs.launchpad.net/neutron/+bug/1865889 Related bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2013820 This bug is related to OVN backend. "segments" service plugin must be enabled. When a new segment is created (for example when a network is created), if this segment is associated to a physnet (flat and vlan type networks) and there is an L2 agent is running on a host with this physnet, a new "SegmentHostMappings" register is created. This segment links this new segment with the host. That means we link a segment with a host when (1) a physnet is mapped in a host and (2) a L2 agent is deployed in this host (and informs about it). In OVN the physnet <-> host mapping is done using the OVS DB [1]: $ ovs-vsctl set open . external-ids:ovn-bridge-mappings=provider:br-provider When an OVS DB is updated, the corresponding OVN SB chassis register is updated. This event is captured in Neutron. Neutron retrieves the current segments associated to the configured physnets (in the example "provider") and filters by network type (flat and vlan only). If any of those segments has no "SegmentHostMappings", a new register is created. However when a new segment is created, OVN mech driver does not correctly check if this segment is located in an agent [2]. Because OVN mech driver has no "agent_type", this method never maps the new created segment with a host. As reported in the bugzilla #2013820, OVN can be deployed with DHCP agents (for baremetal servers with Ironic). When a new network (and the corresponding segment) is created and a new subnet is added to this network, the DHCP agent receives this update. But Neutron server [3] reports this subnet as "non_local_subnets" because there is no mapping between this segment and the DHCP host. Because of this, the DHCP deletes/do not create the DHCP namespace and the DHCP port. [1]https://docs.openstack.org/networking-ovn/2.0.1/refarch/provider-networks.html [2]https://github.com/openstack/neutron/blob/f97baa0b16687453735e46e7a0f73fe03d7d4db7/neutron/plugins/ml2/plugin.py#L2351-L2357 [3]https://github.com/openstack/neutron/blob/9241c76b04e6745cc648ee42037cfe6ddad3600a/neutron/api/rpc/handlers/dhcp_rpc.py#L210-L257 To manage notifications about this bug go to: https://bugs.launchpad.net/neutron/+bug/1949967/+subscriptions -- Mailing list: https://launchpad.net/~yahoo-eng-team Post to : [email protected] Unsubscribe : https://launchpad.net/~yahoo-eng-team More help : https://help.launchpad.net/ListHelp
