CAIN-42 cluster fault-test, run 2 (extended convergence observation). Generated from the bundle's recorded observations.

Verify (python3 + `cryptography`; the verifier imports nothing from CAIN):
  curl -O https://cainstudio.online/evidence/cluster-fault-test-2026-09-21-run2/bundle.json
  curl -o verify_cluster_evidence.py https://cainstudio.online/evidence/cluster-fault-test-2026-09-21-run2/verify_cluster_evidence.py.txt
  python3 verify_cluster_evidence.py bundle.json
Expected: "VERIFIED: 33/33 checks. Signatures and recorded agreement only; not independence, not fault tolerance, not independent review."

What was observed (disposable 4-node twin of the test cluster; same image; PBFT n=4, f=1, quorum 3):
 - S1 commit with all 4: COMMITTED, 4 signers verified independently
 - S2 one node crashed: COMMITTED with 3 signers (quorum 3 of 4)
 - S3 crashed node restarted: reachable=True; converged within 121.4s = False; sequences {'cain-evid-node-1': 2, 'cain-evid-node-2': 2, 'cain-evid-node-3': 2, 'cain-evid-node-4': 1}
 - S4 two nodes crashed (beyond f=1): status=CONSENSUS_TIMEOUT, committed=False, primary sequence advanced without a commit=True
 - S5 both restarted: converged before next commit=False (sequences {'cain-evid-node-1': 3, 'cain-evid-node-2': 2, 'cain-evid-node-3': 2, 'cain-evid-node-4': 1}); next commit COMMITTED with 4 signers; converged after it=True (sequences {'cain-evid-node-1': 4, 'cain-evid-node-2': 4, 'cain-evid-node-3': 4, 'cain-evid-node-4': 4})

How to read it: state-proof signatures, quorum-certificate signers and cross-node agreement are checked independently of CAIN. Convergence and fault-recovery are OBSERVATIONS, not proofs.
Notable: a restarted node did not catch up on its own within the polled window; it converged when the next request committed.

NOT PROVEN: independent failure domains (one host, one image, one Docker daemon); network partitions; a malicious (equivocating) validator on the live wire; long-duration behaviour; the LIVE local test cluster was not fault-injected (only a disposable twin was); the older remote cluster-cain-001 (quorum 2, no PBFT endpoints) is NOT covered and does not meet the 2f+1 rule; no third party has reviewed this
Status: PRE-PRODUCTION. Same-author evidence; not independent review.
bundle_sha256=78a2966f4ed70060a3a49470c305326c0dc2dac3d11d337e14ab680ae9f91bca