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Service Fabric Phase 5 — delivered tranche

This cumulative kit delivers the state-plane/HA tranche on top of v4 while deliberately retaining the v4 TC/XDP ABI.

Delivered​

  1. Bounded HA delta journal in FluxVM

    • monotonic sequence numbers;
    • source acknowledgement watermark;
    • bounded replay retention;
    • gap detection and explicit reset_required;
    • full-snapshot barrier for history gaps;
    • per-service standby replay cursor;
    • whitelisted conntrack/NAT maps only.

  2. Streaming/delta replication orchestration in Fabric

    • durable per source/target cursor store;
    • per-target catch-up loops;
    • full-snapshot fallback on a journal gap;
    • source journal acknowledgement only to the minimum replicated target cursor;
    • replay-safe idempotent target import.

  3. Durable edge lease controller

    • atomic JSON state store;
    • persistent per-service fencing epoch high-water marks (no ABA reuse);
    • healthy lease expiry extension without epoch churn;
    • expired-lease compaction while retaining epoch history;
    • withdraw-before-release for unhealthy edges;
    • deterministic replacement selection;
    • replacement service is staged with advertisement disabled;
    • conntrack state is seeded before advertisement;
    • local FluxVM advertisement readiness is verified before the replacement counts as active.

  4. Incremental BPF service-intent reconciliation

    • desired map image is calculated in userspace;
    • unchanged map entries are left untouched;
    • only changed/new entries are updated;
    • stale service-intent entries are deleted;
    • forward conntrack, reverse NAT and backend telemetry remain lifecycle state and are not cleared;
    • the existing update guard remains fail-closed if reconciliation fails.

  5. Cumulative v4 integration fixes

    • ServiceFabricConfig carries EDT and OTLP settings required by v4;
    • fluxvm-network enables reqwest's JSON feature for OTLP export;
    • FluxVM REST exposes FluxScope flow/OTLP endpoints and v5 delta endpoints;
    • Fabric driver-core/fabricd carry v4 service performance fields through to service-lb.

ABI decision​

SERVICE_SCHEMA_VERSION remains 4 because v5 does not change TC/XDP map layouts. The v5 changes are state/control-plane semantics around the existing v4 BPF ABI. This avoids an unnecessary BPF reload and verifier migration merely to add HA journal/lease behavior.