hyperledger/fabric · error

error writing genesis block: %s

Error message

error writing genesis block: %s

What it means

Returned by doOutputBlock when writeFile fails to persist the generated genesis block to the output path — the block was built successfully, but the filesystem write (permissions, unwritable directory, disk error) failed. The underlying OS error is interpolated into the message.

Source

Thrown at cmd/configtxgen/main.go:52

		return errors.WithMessage(err, "could not create bootstrapper")
	}
	logger.Info("Generating genesis block")
	if config.Orderer == nil {
		return errors.New("refusing to generate block which is missing orderer section")
	}
	if config.Consortiums != nil {
		logger.Error("Warning: 'Consortiums' should be nil since system channel is no longer supported in Fabric v3.x")
	} else {
		if config.Application == nil {
			return errors.New("refusing to generate application channel block which is missing application section")
		}
		logger.Info("Creating application channel genesis block")
	}
	genesisBlock := pgen.GenesisBlockForChannel(channelID)
	logger.Info("Writing genesis block")
	err = writeFile(outputBlock, protoutil.MarshalOrPanic(genesisBlock), 0o640)
	if err != nil {
		return fmt.Errorf("error writing genesis block: %s", err)
	}
	return nil
}

func doOutputChannelCreateTx(conf, baseProfile *genesisconfig.Profile, channelID string, outputChannelCreateTx string) error {
	logger.Info("Generating new channel configtx")

	var configtx *cb.Envelope
	var err error
	if baseProfile == nil {
		configtx, err = encoder.MakeChannelCreationTransaction(channelID, nil, conf)
	} else {
		configtx, err = encoder.MakeChannelCreationTransactionWithSystemChannelContext(channelID, nil, conf, baseProfile)
	}
	if err != nil {
		return err
	}

View on GitHub (pinned to 2736b63f8f)

Solutions

1. Check that the output directory exists and the process has write permission
2. Free disk space or resolve the cause shown in the wrapped error
3. Pass a valid writable file path via -outputBlock

When it happens

Trigger: Thrown at cmd/configtxgen/main.go:52 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/8f41a5e39d180749. Report an issue: GitHub.