BridgePort Protection Group HLD for EVPN L3 multihoming

[pbrisset]

Summary

High-Level Design for bridge-port primary/backup protection in SONiC EVPN L3 multihoming.

The design protects a local bridge port with an ECMP backup group of peer P2P VXLAN tunnels. On local access-link failure, hardware can switch routed traffic to peer VTEPs without route, neighbor, or MAC reprogramming.

Highlights

• Defines FRR-to-SONiC FPM messages for backup tunnel members, groups, and bridge-port bindings.
• Introduces bpProtOrch to attach the FRR-derived backup NHG to the protected bridge port.
• Reuses L2NhgOrch and per-peer P2P VXLAN tunnels.
• Defines RMAC placement on the P2P tunnel and VRF/L3VNI selection through tunnel maps.
• Covers CONFIG_DB, STATE_DB, CLI/YANG, warm boot, reconciliation, FDB/neighbor lifecycle, and test requirements.
• Documents hardware protection, software fallback, recovery policy, and platform constraints.

[mssonicbld]

/azp run

[azure-pipelines]

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