hyperledger/fabric · error

Attempted to set the batch size max message count to an inva

Error message

Attempted to set the batch size max message count to an invalid value: 0

What it means

OrdererConfig.Validate() calls validateBatchSize, which requires BatchSize.MaxMessageCount to be non-zero. A value of 0 would allow batches of unlimited/unusable message counts, so the library rejects it during orderer config validation. This is a semantic validation of the ab.BatchSize proto decoded from the Orderer group.

Source

Thrown at common/channelconfig/orderer.go:216

	return capabilities.NewOrdererProvider(oc.protos.Capabilities.Capabilities)
}

func (oc *OrdererConfig) Validate() error {
	for _, validator := range []func() error{
		oc.validateBatchSize,
		oc.validateBatchTimeout,
	} {
		if err := validator(); err != nil {
			return err
		}
	}

	return nil
}

func (oc *OrdererConfig) validateBatchSize() error {
	if oc.protos.BatchSize.MaxMessageCount == 0 {
		return fmt.Errorf("Attempted to set the batch size max message count to an invalid value: 0")
	}
	if oc.protos.BatchSize.AbsoluteMaxBytes == 0 {
		return fmt.Errorf("Attempted to set the batch size absolute max bytes to an invalid value: 0")
	}
	if oc.protos.BatchSize.PreferredMaxBytes == 0 {
		return fmt.Errorf("Attempted to set the batch size preferred max bytes to an invalid value: 0")
	}
	if oc.protos.BatchSize.PreferredMaxBytes > oc.protos.BatchSize.AbsoluteMaxBytes {
		return fmt.Errorf("Attempted to set the batch size preferred max bytes (%v) greater than the absolute max bytes (%v).", oc.protos.BatchSize.PreferredMaxBytes, oc.protos.BatchSize.AbsoluteMaxBytes)
	}
	return nil
}

func (oc *OrdererConfig) validateBatchTimeout() error {
	var err error
	oc.batchTimeout, err = time.ParseDuration(oc.protos.BatchTimeout.Timeout)
	if err != nil {
		return fmt.Errorf("Attempted to set the batch timeout to a invalid value: %s", err)

View on GitHub (pinned to 2736b63f8f)

Solutions

1. Set MaxMessageCount to a positive integer (e.g. 500, the Fabric default) in the channel profile's Orderer.BatchSize section and regenerate the config.
2. If constructing ab.BatchSize in code, populate MaxMessageCount before marshaling into the ConfigValue.
3. If BatchSize is missing entirely, add the full BatchSize block (MaxMessageCount, AbsoluteMaxBytes, PreferredMaxBytes) to the configtx profile.
4. In tests, use a populated BatchSize fixture before calling the validation path.

Example fix

// before (configtx.yaml)
Orderer:
  BatchSize:
    AbsoluteMaxBytes: 10 MB
    PreferredMaxBytes: 2 MB
// after
Orderer:
  BatchSize:
    MaxMessageCount: 500
    AbsoluteMaxBytes: 10 MB
    PreferredMaxBytes: 2 MB

func checkBatchSize(bs *ab.BatchSize) error {
	if bs == nil || bs.MaxMessageCount == 0 {
		return errors.New("BatchSize.MaxMessageCount must be a positive integer (e.g. 500)")
	}
	return nil
}

func hasValidMaxMessageCount(bs *ab.BatchSize) bool {
	return bs != nil && bs.MaxMessageCount > 0
}

_, err := channelconfig.NewChannelConfig(env.Config)
if err != nil {
	if strings.Contains(err.Error(), "max message count to an invalid value: 0") {
		return fmt.Errorf("fix Orderer.BatchSize.MaxMessageCount in configtx.yaml (set to e.g. 500) and regenerate: %w", err)
	}
	return err
}

When it happens

Trigger: Calling NewOrdererConfig (via NewChannelConfig, or TestBatchSize in tests) with an orderer group whose BatchSize value has MaxMessageCount == 0 — typically because the BatchSize proto was left as a zero-valued struct or only partially populated.

Common situations: Generating channel config programmatically and forgetting to set MaxMessageCount; configtx profiles omitting BatchSize so defaults are never applied; test fixtures constructing ab.BatchSize{} empty; configtxlator edits that zero out the field.

Understand the failure class

Background: "Invalid value" and "allowed values are" config errors: what your library rejected and how to fix it — this error's family across 41 libraries.

Related errors

• Attempted to set the batch size absolute max bytes to an inv
• Attempted to set the batch size preferred max bytes to an in
• Attempted to set the batch size preferred max bytes (%v) gre
• Attempted to set the batch timeout to a non-positive value:
• unexpected missing policy %s for item %s

AI-assisted analysis of hyperledger/fabric@2736b63f8f (2026-09-04). Data as JSON: /api/errors/616122f892be064e. Report an issue: GitHub.