Wire V2 promotion into production binary:
- Add --block.v2Promotion CLI flag on weed master (default false)
- MasterOption.BlockV2Promotion → NewMasterServer wires flag + querier
- defaultBlockVSQueryEvidence placeholder (returns explicit error until
proto regen on M01 enables gRPC evidence RPC)
Fix three fail-closed violations found by tester:
1. blockV2Promotion=true + nil querier now fails closed with explicit
log instead of silently falling back to V1
2. Partial evidence (any candidate query failed) now fails closed —
unreachable candidate may be the most durable, promoting from
incomplete evidence violates durability-first ordering
3. Clear EngineProjectionMode in applyPromotionLocked (already in
previous commit, verified in tests here)
2 new tests: NilQuerier_FailsClosed, PartialEvidenceFailure_FailsClosed.
Total T3 tests: 7, all pass. Existing V1 failover tests unaffected.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Wire V2 promotion into the real master failover decision path:
promoteReplica() now dispatches to promoteReplicaV2() when
blockV2Promotion flag is true. V2 path queries each candidate for
fresh evidence via pluggable BlockPromotionEvidenceQuerier, selects
by CommittedLSN (durability-first), and fail-closes when no eligible
candidate exists. No silent fallback to V1.
Feature flag: blockV2Promotion bool on MasterServer. When false,
existing promoteReplicaV1() (health-score-first) is used unchanged.
Flag is explicit and observable, not a hidden rescue path.
Registry: add PromoteReplicaByServer() for V2 path where master
already knows the winner. Clear stale EngineProjectionMode in
applyPromotionLocked (complements T1 turnover fix).
T2 fix: fail-closed when V2 core projection is absent —
Eligible=false with reason "missing_engine_projection". CommittedLSN
from core used unconditionally (no WALHeadLSN overstatement).
5 T3 integration tests: higher CommittedLSN wins, all-ineligible
fail-closed, evidence-failure fail-closed, flag-off uses legacy,
epoch bump + assignment enqueue only after selection.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Lookup() and ListAll() now return value copies (not pointers to
internal registry state). Callers can no longer mutate registry
entries without holding a lock.
Added clone() on BlockVolumeEntry with deep-copied Replicas slice.
Added UpdateEntry(name, func(*BlockVolumeEntry)) for locked mutation.
ListByServer() also returns copies.
Migrated 1 production mutation (ReplicaPlacement + Preset in create
handler) and ~20 test mutations to use UpdateEntry.
5 new copy-correctness tests: Lookup returns copy, Replicas slice
isolated, ListAll returns copies, UpdateEntry mutates, UpdateEntry
not-found error.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Six-task checkpoint hardening the promotion and failover paths:
T1: 4-gate candidate evaluation (heartbeat freshness, WAL lag, role,
server liveness) with structured rejection reasons.
T2: Orphaned-primary re-evaluation on replica reconnect (B-06/B-08).
T3: Deferred timer safety — epoch validation prevents stale timers
from firing on recreated/changed volumes (B-07).
T4: Rebuild addr cleanup on promotion (B-11), NVMe publication
refresh on heartbeat, and preflight endpoint wiring.
T5: Manual promote API — POST /block/volume/{name}/promote with
force flag, target server selection, and structured rejection
response. Shared applyPromotionLocked/finalizePromotion helpers
eliminate duplication between auto and manual paths.
T6: Read-only preflight endpoint (GET /block/volume/{name}/preflight)
and blockapi client wrappers (Preflight, Promote).
BUG-T5-1: PromotionsTotal counter moved to finalizePromotion (shared
by both auto and manual paths) to prevent metrics divergence.
24 files changed, ~6500 lines added. 42 new QA adversarial tests.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
