{"record":{"id":"6e1b491733329b1c","repo":"hyperledger/fabric","slug":"error-opening-block-file-s","errorCode":null,"errorMessage":"error opening block file %s","messagePattern":"error opening block file (.+?)","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"common/ledger/blkstorage/block_stream.go","lineNumber":60,"sourceCode":"\n// blockPlacementInfo captures the information related\n// to block's placement in the file.\ntype blockPlacementInfo struct {\n\tfileNum          int\n\tblockStartOffset int64\n\tblockBytesOffset int64\n}\n\n// /////////////////////////////////\n// blockfileStream functions\n// //////////////////////////////////\nfunc newBlockfileStream(rootDir string, fileNum int, startOffset int64) (*blockfileStream, error) {\n\tfilePath := deriveBlockfilePath(rootDir, fileNum)\n\tlogger.Debugf(\"newBlockfileStream(): filePath=[%s], startOffset=[%d]\", filePath, startOffset)\n\tvar file *os.File\n\tvar err error\n\tif file, err = os.OpenFile(filePath, os.O_RDONLY, 0o600); err != nil {\n\t\treturn nil, errors.Wrapf(err, \"error opening block file %s\", filePath)\n\t}\n\tvar newPosition int64\n\tif newPosition, err = file.Seek(startOffset, 0); err != nil {\n\t\treturn nil, errors.Wrapf(err, \"error seeking block file [%s] to startOffset [%d]\", filePath, startOffset)\n\t}\n\tif newPosition != startOffset {\n\t\tpanic(fmt.Sprintf(\"Could not seek block file [%s] to startOffset [%d]. New position = [%d]\",\n\t\t\tfilePath, startOffset, newPosition))\n\t}\n\ts := &blockfileStream{fileNum, file, bufio.NewReader(file), startOffset}\n\treturn s, nil\n}\n\nfunc (s *blockfileStream) nextBlockBytes() ([]byte, error) {\n\tblockBytes, _, err := s.nextBlockBytesAndPlacementInfo()\n\treturn blockBytes, err\n}\n","sourceCodeStart":42,"sourceCodeEnd":78,"githubUrl":"https://github.com/hyperledger/fabric/blob/2736b63f8fd5932511d56fe68b7039d15977f7f6/common/ledger/blkstorage/block_stream.go#L42-L78","documentation":"Wraps the os.OpenFile error when newBlockfileStream cannot open a blockfile (blockfile %s) in read-only mode. The wrapped cause (permission denied, no such file, etc.) is available via errors.Cause or %v unwrapping. It propagates up through newBlockStream, moveToNextBlockfileStream, retrieveFirstBlockNumFromFile, and fetchBlockBytes whenever a block segment file cannot be opened.","triggerScenarios":"newBlockfileStream(rootDir, fileNum, startOffset) calls os.OpenFile(deriveBlockfilePath(rootDir, fileNum), os.O_RDONLY, 0o600) and the open fails — missing file, wrong permissions, bad rootDir, or an I/O error.","commonSituations":"peer.fileSystemPath misconfigured so the ledger directory does not exist; blockfiles deleted or partially copied from another node; running the peer as a user without read permission on the ledger directory; container volume not mounted.","solutions":["Check the wrapped error (%v of the returned error) to see whether it is ENOENT, EACCES, or EIO and fix accordingly","Verify the ledger root directory (peer.fileSystemPath leading to ledgersData/chains) exists and contains the expected blockfile_<n> files","Fix filesystem permissions/ownership so the peer process can read the files","Restore the missing/corrupt blockfile from a backup, snapshot, or re-sync from orderers"],"exampleFix":"// before\ns, err := newBlockStream(dir, 0, 0)\nif err != nil { return err }\n// after: surface the cause and validate the dir first\nif _, err := os.Stat(dir); os.IsNotExist(err) {\n    return fmt.Errorf(\"ledger dir %s missing: %w\", dir, err)\n}\ns, err := newBlockStream(dir, 0, 0)\nif err != nil { return fmt.Errorf(\"open block stream: %w\", err) }","handlingStrategy":"validation","validationCode":"path := deriveBlockfilePath(rootDir, fileNum)\nif info, err := os.Stat(path); err != nil {\n    return fmt.Errorf(\"blockfile %s inaccessible: %w\", path, err)\n} else if !info.Mode().IsRegular() {\n    return fmt.Errorf(\"%s is not a regular file\", path)\n}","typeGuard":null,"tryCatchPattern":"s, err := newBlockfileStream(rootDir, num, offset)\nif err != nil {\n    var perr *os.PathError\n    if errors.As(errors.Cause(err), &perr) && os.IsNotExist(errors.Cause(err)) {\n        return restoreBlockfileFromBackup(perr.Path)\n    }\n    return err\n}","preventionTips":["Pin peer.fileSystemPath in config and verify it at startup","Run the peer as a single consistent user so permissions never drift","Confirm volumes are mounted before peer start (entrypoint check)","Monitor ledger directory for unexpected deletions"],"tags":["fabric","ledger","filesystem","file-open"],"backgroundTag":"file-not-found","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"}