What causes "error writing to temp file '%s'" in hyperledger/fabric?

Inspect the wrapped cause (Unwrap/`errors.Cause`) to identify the underlying OS error

error writing to temp file '%s'

Error message

error writing to temp file '%s'

What it means

This is the wrapper message applied to any failure of the temp-file write in WriteFile: it wraps either the raw os error from tmpFile.Write or the short-write error ('failed to write the entire content...') with the temp file's name for diagnostics.

Source

Thrown at core/chaincode/persistence/persistence.go:61

// if the operation crashes midway we're not stuck with a bad package
func (f *FilesystemIO) WriteFile(path, name string, data []byte) error {
	if path == "" {
		return errors.New("empty path not allowed")
	}
	tmpFile, err := os.CreateTemp(path, ".ccpackage.")
	if err != nil {
		return errors.Wrapf(err, "error creating temp file in directory '%s'", path)
	}
	defer os.Remove(tmpFile.Name())

	if n, err := tmpFile.Write(data); err != nil || n != len(data) {
		if err == nil {
			err = errors.Errorf(
				"failed to write the entire content of the file, expected %d, wrote %d",
				len(data), n,
			)
		}
		return errors.Wrapf(err, "error writing to temp file '%s'", tmpFile.Name())
	}

	if err := tmpFile.Close(); err != nil {
		return errors.Wrapf(err, "error closing temp file '%s'", tmpFile.Name())
	}

	if err := os.Rename(tmpFile.Name(), filepath.Join(path, name)); err != nil {
		return errors.Wrapf(err, "error renaming temp file '%s'", tmpFile.Name())
	}

	return nil
}

// Remove removes a file from the filesystem - used for rolling back an in-flight
// Save operation upon a failure
func (f *FilesystemIO) Remove(name string) error {
	return os.Remove(name)
}

View on GitHub (pinned to 2736b63f8f)

Solutions

Inspect the wrapped cause (Unwrap/`errors.Cause`) to identify the underlying OS error
Free disk space or raise storage limits, then retry the install
Check host/container storage logs (dmesg, docker events) for I/O errors
Ensure only the peer process writes to the install directory

Defensive patterns

Strategy: retry

Validate before calling

if err := ensureDiskSpace(path, uint64(len(data))+1<<20); err != nil { return err }

Try / catch

err := io.WriteFile(path, name, data)
for i := 0; err != nil && i < 2 && isTransientIO(err); i++ {
    time.Sleep(backoff)
    err = io.WriteFile(path, name, data)
}
if err != nil { return fmt.Errorf("saving chaincode package: %w", err) }

Prevention

Monitor host/container storage health (dmesg, SMART) for the peer volume
Avoid shared writes to the chaincode install directory by external processes
Keep headroom on the data volume to absorb large package writes

When it happens

Trigger: Any error returned by tmpFile.Write(data) — bad file descriptor, I/O error, disk full, or the short-write condition — while saving a chaincode package.

Common situations: Storage device errors on the peer's host; container ephemeral storage limits exhausted during `peer lifecycle chaincode install`; concurrent processes interfering with the temp file.

Related errors

AI-assisted analysis of hyperledger/fabric@2736b63f8f (2026-09-04). Data as JSON: /api/errors/98bf229b047f2153. Report an issue: GitHub.