Extended chaos test coverage from 14 to 19 tests and created
comprehensive documentation for safe shard migrations.
New Chaos Tests:
- cutover_chaos_network_partition_new_node: Network partition during cutover
- cutover_chaos_drain_timeout_boundary: Drain timeout boundary conditions
- cutover_chaos_concurrent_migrations: Multiple simultaneous migrations
- cutover_chaos_partial_shard_failure: Varying failure rates per shard
- cutover_chaos_coordinator_crash_recovery: Coordinator crash and restart
Documentation:
- docs/chaos_testing_report.md: Test coverage, findings, recommendations
- docs/migration_runbook.md: Operational procedures, rollback, troubleshooting
- notes/bf-4d9a.md: Task summary and completion report
Key Findings:
- Delta pass provides 0-loss cutover (validated across 19 tests)
- AE on + delta on: 0.000% loss (recommended)
- AE off + delta on: 0.000% loss (safe but no defense-in-depth)
- AE off + delta skipped: ~2% loss (blocked by coordinator)
All success criteria met:
✅ Cutover boundary chaos tests pass with anti-entropy enabled
✅ Data loss windows without anti-entropy documented and bounded
✅ Release notes include clear guidance on anti-entropy during migrations
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Verified that the compatibility matrix deliverable is complete:
- docs/dump-import/compatibility-matrix.md already exists (created in bf-3gfw)
- All acceptance criteria met:
* Matrix published with comprehensive failure mode enumeration
* Each "broadcast needed" row has workaround or enhancement link
* CLI output format documented to reference matrix
- All three potential failure modes from task description are covered
- Streaming mode limitations clearly documented
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Deferred to v2.x per research findings. Research doc and prototype
already committed in P12.OP2 commits.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
## Work Completed
- Verified and documented comprehensive dump import compatibility matrix
- Documented decision tree for choosing streaming vs broadcast mode
- Catalogued all dump variants and their streaming import compatibility
- Documented field conflicts, fallback triggers, and operator guidance
- Created summary in notes/bf-3gfw.md
## Success Criteria Met
- Complete matrix of dump variants and their supported import modes (✅)
- Clear operator guidance on when to use each mode (✅)
- Implementation/testing deferred to bead miroir-zc2.5
## Documentation
Compatibility matrix already exists at:
docs/dump-import/compatibility-matrix.md
## Related
- Parent epic: miroir-zc2 (Phase 12 — Open Problems + Research)
- Plan §13.9: Streaming routed dump import
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
