hyperledger/fabric · error
error while closing the snapshot file
Error message
error while closing the snapshot file: %s
What it means
Done calls c.file.Sync() to force written data to stable storage; if the OS-level sync fails, the raw error is returned (no wrap). A failure here means data may not be durably persisted and the snapshot cannot be trusted as complete. The hash is not returned because the file finalization did not succeed.
Solutions
- Inspect the raw OS error returned by Sync
- Avoid snapshot output on network filesystems with unreliable fsync; write to local disk
- Retry the export and verify the resulting snapshot hash
Defensive patterns
Strategy: retry
Validate before calling
if err := syscall.Access(snapshotDir, os.O_RDWR); err != nil { return errors.New("snapshot dir not writable") } Try / catch
hash, err := w.Done()
if err != nil {
log.Errorf("sync/close failed for snapshot %s: %v", path, err)
w.Close(); return err // retry the whole export
} Prevention
- Prefer local filesystems with reliable fsync over NFS
- Retry the entire export if Sync fails — the snapshot is not durable
- Monitor storage health (EIO) on the node
When it happens
Trigger: c.file.Sync() returns an error during Done (after a successful Flush).
Common situations: ENOSPC/EIO on the underlying storage, NFS/network filesystems that don't support fsync properly, or container storage drivers rejecting fsync.
Related errors
- error while closing the snapshot file
- error while flushing to the snapshot file
- error while opening the snapshot file
- error while reading from snapshot file
- error while reading from the snapshot file
AI-assisted analysis of hyperledger/fabric@2736b63f8f (2026-09-04).
Data as JSON: /api/errors/9837f107d51c4540.
Report an issue: GitHub.
Appendix: source
Thrown at common/ledger/snapshot/file.go:108
// EncodeUVarint encodes and appends a number to the data stream
func (c *FileWriter) EncodeUVarint(u uint64) error {
n := binary.PutUvarint(c.varintReusableBuf, u)
if _, err := c.multiWriter.Write(c.varintReusableBuf[:n]); err != nil {
return errors.Wrapf(err, "error while writing data to the snapshot file: %s", c.file.Name())
}
return nil
}
// Done closes the snapshot file and returns the final hash of the data stream
func (c *FileWriter) Done() ([]byte, error) {
if err := c.bufWriter.Flush(); err != nil {
return nil, errors.Wrapf(err, "error while flushing to the snapshot file: %s ", c.file.Name())
}
if err := c.file.Sync(); err != nil {
return nil, err
}
if err := c.file.Close(); err != nil {
return nil, errors.Wrapf(err, "error while closing the snapshot file: %s ", c.file.Name())
}
return c.hasher.Sum(nil), nil
}
// Close closes the underlying file, if not already done. A consumer can invoke this function if the consumer
// encountered some error and simply wants to abandon the snapshot file creation (typically, intended to be used in a defer statement)
func (c *FileWriter) Close() error {
if c == nil {
return nil
}
return errors.Wrapf(c.file.Close(), "error while closing the snapshot file: %s", c.file.Name())
}
// FileReader reads from a ledger snapshot file. This is expected to be used for loading the ledger snapshot data
// during bootstrapping a channel from snapshot. The data should be read, using the functions `DecodeXXX`,
// in the same sequence in which the data was written by the functions `EncodeXXX` in the `FileCreator`.
// Note that the FileReader does not verify the hash of stream and it is expected that the hash has been verified
// by the consumer. Later, if we decide to perform this, on-the-side, while loading the snapshot data, the FileRedear,View on GitHub (pinned to 2736b63f8f)