{"record":{"id":"32f8a66337ca70a3","repo":"hyperledger/fabric","slug":"error-decoding-the-block-metadata","errorCode":null,"errorMessage":"error decoding the block metadata","messagePattern":"error decoding the block metadata","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"common/ledger/blkstorage/block_serialization.go","lineNumber":170,"sourceCode":"\t\t}\n\t\tdata.Data = append(data.Data, txEnvBytes)\n\t\tidxInfo := &txindexInfo{txID: txid, loc: &locPointer{txOffset, buf.GetBytesConsumed() - txOffset}}\n\t\ttxOffsets = append(txOffsets, idxInfo)\n\t}\n\treturn data, txOffsets, nil\n}\n\nfunc extractMetadata(buf *buffer) (*common.BlockMetadata, error) {\n\tmetadata := &common.BlockMetadata{}\n\tvar numItems uint64\n\tvar metadataEntry []byte\n\tvar err error\n\tif numItems, err = buf.DecodeVarint(); err != nil {\n\t\treturn nil, errors.Wrap(err, \"error decoding the length of block metadata\")\n\t}\n\tfor i := uint64(0); i < numItems; i++ {\n\t\tif metadataEntry, err = buf.DecodeRawBytes(false); err != nil {\n\t\t\treturn nil, errors.Wrap(err, \"error decoding the block metadata\")\n\t\t}\n\t\tmetadata.Metadata = append(metadata.Metadata, metadataEntry)\n\t}\n\treturn metadata, nil\n}\n","sourceCodeStart":152,"sourceCodeEnd":176,"githubUrl":"https://github.com/hyperledger/fabric/blob/2736b63f8fd5932511d56fe68b7039d15977f7f6/common/ledger/blkstorage/block_serialization.go#L152-L176","documentation":"Within extractMetadata, each metadata entry is read as a length-prefixed raw byte slice. Failure to decode an entry wraps this error. The count was readable but the entry bytes themselves are missing or corrupted.","triggerScenarios":"deserializeBlock/extractSerializedBlockInfo where the block bytes end (or a length prefix overruns) inside the metadata entries after a successful metadata count decode.","commonSituations":"Truncated final block after an unclean shutdown; corrupted block file tails; tools that rewrote blocks with wrong length framing.","solutions":["Copy the affected block from a healthy peer or restore from backup.","Reset and resync the peer's ledger for the channel.","Validate any custom block-extraction tooling against serializeBlock's exact encoding.","Enable storage redundancy and verify filesystem integrity after host crashes."],"exampleFix":"null","handlingStrategy":"try-catch","validationCode":"if numMetadataItems == 0 {\n    return errors.New(\"block metadata count decoded as zero; suspect corruption\")\n}","typeGuard":"func isMetadataEntryDecodeFailure(err error) bool {\n    return err != nil && strings.Contains(err.Error(), \"error decoding the block metadata\")\n}","tryCatchPattern":"md, err := extractMetadata(buf)\nif err != nil {\n    if isMetadataEntryDecodeFailure(err) {\n        // replace block file from healthy replica or rebuild ledger\n    }\n    return err\n}","preventionTips":["Run an odd number of peers/orderers and cross-check block hashes between nodes to detect corruption.","Never modify committed block files in place.","Use journaling/robust filesystems for ledger paths.","Automate ledger rebuild runbooks so recovery from corrupted blocks is routine."],"tags":["hyperledger-fabric","ledger","serialization","corruption"],"backgroundTag":"ledger-block-corruption","analyzedSha":"2736b63f8fd5932511d56fe68b7039d15977f7f6","analyzedAt":"2026-09-04T08:52:36.465Z","contentChangedAt":"2026-09-04T08:52:36.465Z","schemaVersion":2},"datasetVersion":"2026-09-08T10:18:20.063Z"}