Stability and internals. load_db_migration_drivers was repaired, and the quota module drops the unused set_all_quota_usage_dirty() helper. A functional test now tracks socket fds so they get cleaned up between runs.

CI. Failing tests on CentOS 10 Stream are temporarily skipped to unblock the gate.

Overall the week is dominated by OVN LSP host-info handling, with roughly a dozen of the fifteen merges touching the OVN backend or its stable-branch backports.

OVN backend. A new TimedOnetimeEvent primitive lands for auto-expiring OVSDB watchers, and RPC workers now use the base OVN IDL with notification events disabled (backported across four branches). Several race and correctness fixes: HAChassisGroupRouterEvent no longer sets options.chassis on physnet routers, an HA_Chassis_Group race in port create/update is closed, UpdateLRouterCommand now honors if_exists, ChassisAgentTypeChangeEvent respects its events attribute, LSP host info updates are skipped for router ports, and update_virtual_port_parent_host handles PortNotFound. A BGP change limits lrp_mac to the local chassis.

Config and stability. Missing min/max bounds were added across timeout, interval, count, size, HA conntrackd, and BGP VRF ID options. Segments code now catches missing RPs in _delete_nova_inventory, and the metadata proxy socket is closed on GC.

Docs and CI. New pages cover stadium API groups and supported quota resources, LinuxBridge references were pruned, agentic coding guidance was added, and functional-FIPS venv prep moved to Python 3.12.

OVN and segments stability. A race condition in HA_Chassis_Group during port create/update landed on master and was backported to two stable branches. The _delete_nova_inventory path in the segments plugin now catches "resource provider not found," also delivered with a stable backport. Elsewhere, ovs_create_tap was flipped to True by default (see https://review.opendev.org/c/openstack/neutron/+/994752), and an ugly traceback when attaching a subnet to a router was silenced.

Test and tooling maintenance. Four near-identical patches updated the base_mac config override in unit tests across branches, a functional test now waits for the LSP tag to be set before proceeding, bash files gained proper shebangs for linting, and the suite was adapted to a new testtools release.

OVN and EVPN. Several backend fixes landed: the OVN client now resets only LRP options keys it actually defined, missing neutron:network_name on sibling LRPs is tolerated, the EVPN HA Chassis Group is cleaned up on router deletion, and EVPN callbacks gained explicit priorities.

Stability. Retries were added around NetlinkDumpInterrupted, _delete_nova_inventory now catches RP-not-found in segments, PVLAN multinode support was repaired, and allowed_network_downtime was bumped to 7.0 across four backports. A flaky test_router_update_with_too_many_routes was also pinned down.

Housekeeping. CentOS CI jobs moved to 10-stream, a CentOS 9 / FRR 8.5 VRF-delete skip was reverted, and four pylint cleanup passes (iterating-dictionary, nested-blocks, unnecessary-pass, using-enumerate) swept the tree.

EVPN and FRR driver. A sizable round of work on the FRR-based EVPN stack: Port_Binding event handling was fixed (~260 lines), FrrDriver's vtysh invocation now accepts --vty_socket, frrinit.sh was reworked to spawn background daemons, rootwrap filters for vtysh landed, and the FrrFixture now explicitly creates its log directories. A vrf-delete test is skipped on CentOS 9 / FRR 8.5.

Stability and bug fixes. A quota-details API error with unloaded service plugins was fixed and backported to three stable branches. Other fixes: FloatingIPDNS rows are now deleted on FIP disassociation, an OVN FIP-deletion race was closed, tun_br is guarded in _restore_local_vlan_map when there is no br-tun, extension flows are reinstalled after an OVS restart, allowed_address_pairs are included in CT_MARK_INVALID conntrack cleanup, the maintenance worker lock is now scoped to the worker, and metadata response headers were cleaned up.

Tooling. A new ~890-line Neutron dependency change detection tool landed; elsewhere, pylint superfluous-parens warnings were cleared, os-ken bumped to 4.2.1, and some unused OVN metadata grenade and zuul jobs removed.

Other feature surface. A DNS forwarder L2 extension landed, and PVLAN gained policy rules, a DevStack service-plugin toggle, and a fix to the update response payload. Policy check strings were migrated wholesale to neutron-lib, and port RBAC policies were tightened to require network ownership.

Stability and bug fixes. OVN got several correctness fixes: passing gateway LRPs to _check_external_ips_changed, avoiding a nested transaction in _delete_port's virtual parent check, reading LSP up state from the IDL cache, switching to LSP.tag_request, and using idl.has_lock for OVSDB lock checks. The OVS agent now skips OF operations for ports with invalid ofport and defers them in _process_port (with backports). Other fixes covered floating-IP PF validation, quota details with unloaded service plugins, OVS firewall conntrack cleanup, cross-project router conntrack helper access (three backports), update_router:enable_default_route_* policies (four backports), and ignoring designate NotFound on PTR delete.

Elsewhere. CI moved the BGP job to experimental while adding a compute1 node to its multinode tempest variant, and the neutron.tests contrib module was removed.

EVPN and BGP scaffolding. Two adjacent efforts moved forward substantially. EVPN gained a DB model for the evpn_vni attribute and port_binding events feeding the OVN agent's EVPN extension. The BGP side introduced a new InterconnectBridge with peer-to-peer flows, ARP proxy on the main BGP router, a fixed (non-configurable) main BGP router name, and a rule preventing route learning from the main BGP LRP. A new FrrService test fixture supports this work.

Stability and policy. The OVS firewall now clears invalid conntrack entries after OF rules are applied, backported across three branches, and a tunnel-network detection fix using tunnel-type driver ranges landed on master plus two stable branches. Other fixes cover invalid MAC handling in metadata agent port provisioning, a worker-lifecycle race, cross-project access to router conntrack helpers, and duplicate AgentSchedulerDbMixin periodic descriptions. New policies expand service-role RBAC for Octavia and allow service role to set port device_id, and an update_l3-router policy was added.

Elsewhere. Documentation now lists all OVN-supported extensions, grenade jobs were dropped from stable/2025.1 CI, and a round of small ORM cleanups replaced first() with one_or_none() and tightened port/rule lookups.

BGP and spine-and-leaf. OVN BGP gained an admin guide for spine-and-leaf fabrics, an EVPN constants module, and a behavior change that always assumes a single provider switch. FRR startup on leaf/spine deployments is now delayed until the controller interfaces actually exist, closing a race during bring-up.

Worker and OVN internals. Periodic thread workers were reorganized into groups with selective wrapping (replacing an earlier "group periodic thread workers together" patch that was reverted), and a DEBUG decorator now traces worker lifecycle. On the OVN side, OVNL3 post-fork init is skipped in non-API workers, and a redundant get_port() was removed from _add_router_ext_gw.

Bug fixes. Port RBAC policies are now correctly required to check network ownership, and VLAN/tunnel network detection now consults the VlanTypeDriver and tunnel type driver ranges instead of guessing. ML2 mechanism drivers are notified in reverse order during port delete, and PF floating IP GET/PUT parent validation was corrected. The RBAC, VLAN, and PF floating IP fixes each shipped across three or four stable branches.

Docs. Substantial new admin documentation landed for server-side processes, notification events and payloads, and policy scope types.

OVN stability. Several long-standing rough edges in the OVN backend were straightened out. A FIP NAT external_mac race when the LSP was already UP was fixed, a shared admin_context leak across OVSDB monitor event handlers was closed, and the OVNL3RouterPlugin now registers its events inside the Neutron API workers. MTU handling for metadata and OVN LB health-monitor tap interfaces was aligned with the network MTU, and BGPWorker was guarded against a missing _reconciler.

API surface. Plural policy names in the tagging controller and floating-IP policy were corrected and backported across four stable branches. Multicast addresses are now rejected in Allowed Address Pairs, and a doc warning was added about QoS low bandwidth limits interacting with MTU.

Maintenance. Periodic thread workers were grouped, model_query was dropped from db/_utils.py, the version module was deprecated, and the pbr runtime-dependency removal was reverted.