hyperledger/fabric · error

failed to create BlockVerificationAssistant

Error message

failed to create BlockVerificationAssistant

What it means

createBFTDeliverer wraps a failure while constructing the updatable block verification assistant (from the last config block's bundle): the policy/consenter information needed to verify pulled blocks could not be assembled.

Source

Thrown at orderer/consensus/smartbft/synchronizer_bft.go:196

	return heights[f]
}

// createBFTDeliverer creates and initializes the BFT block deliverer.
func (s *BFTSynchronizer) createBFTDeliverer(startHeight uint64, myEndpoint string) (BFTBlockDeliverer, error) {
	lastBlock := s.Support.Block(startHeight - 1)
	lastConfigBlock, err := cluster.LastConfigBlock(lastBlock, s.Support)
	if err != nil {
		return nil, errors.Wrapf(err, "failed to retrieve last config block")
	}
	lastConfigEnv, err := deliverclient.ConfigFromBlock(lastConfigBlock)
	if err != nil {
		return nil, errors.Wrapf(err, "failed to retrieve last config envelope")
	}

	var updatableVerifier deliverclient.CloneableUpdatableBlockVerifier
	updatableVerifier, err = s.VerifierFactory.CreateBlockVerifier(lastConfigBlock, lastBlock, s.CryptoProvider, s.Logger)
	if err != nil {
		return nil, errors.Wrapf(err, "failed to create BlockVerificationAssistant")
	}

	clientConfig := s.ClusterDialer.Config // The cluster and block puller use slightly different options
	clientConfig.AsyncConnect = false
	clientConfig.SecOpts.VerifyCertificate = nil

	// The maximal amount of time to wait before retrying to connect.
	maxRetryInterval := s.LocalConfigCluster.ReplicationRetryTimeout
	// The minimal amount of time to wait before retrying. The retry interval doubles after every unsuccessful attempt.
	minRetryInterval := maxRetryInterval / 50
	// The maximal duration of a Sync. After this time Sync returns with whatever it had pulled until that point.
	maxRetryDuration := s.LocalConfigCluster.ReplicationPullTimeout * time.Duration(s.LocalConfigCluster.ReplicationMaxRetries)
	// If a remote orderer does not deliver blocks for this amount of time, even though it can do so, it is replaced as the block deliverer.
	blockCensorshipTimeOut := maxRetryDuration / 3

	bftDeliverer := s.BFTDelivererFactory.CreateBFTDeliverer(
		s.Support.ChannelID(),
		s.syncBuff,

View on GitHub (pinned to 2736b63f8f)

Solutions

1. Check the channel config in the last config block is valid
2. Re-join the node so a clean config is loaded

When it happens

Trigger: Thrown at orderer/consensus/smartbft/synchronizer_bft.go:196 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of hyperledger/fabric@2736b63f8f (2026-09-04). Data as JSON: /api/errors/6910c206bc8a8349. Report an issue: GitHub.