ipfs/kubo · error

unmount: unimplemented

Error message

unmount: unimplemented

What it means

UnmountCmd builds the platform-specific unmount command for a mountpoint; on platforms other than linux (and darwin/other handled branches above) it returns the error 'unmount: unimplemented', meaning ForceUnmount cannot work on this GOOS.

Source

Thrown at fuse/mount/mount.go:74

		return fmt.Errorf("umount timeout")
	case err := <-errc:
		return err
	}
}

// UnmountCmd creates an exec.Cmd that is GOOS-specific
// for unmount a FUSE mount.
func UnmountCmd(point string) (*exec.Cmd, error) {
	switch runtime.GOOS {
	case "darwin":
		return exec.Command("diskutil", "umount", "force", point), nil
	case "linux":
		if _, err := exec.LookPath("fusermount3"); err == nil {
			return exec.Command("fusermount3", "-u", point), nil
		}
		return exec.Command("fusermount", "-u", point), nil
	default:
		return nil, fmt.Errorf("unmount: unimplemented")
	}
}

// ForceUnmountManyTimes attempts to forcibly unmount a given mount,
// many times. It does so by calling diskutil or fusermount directly.
// Attempts a given number of times.
func ForceUnmountManyTimes(m Mount, attempts int) error {
	var err error
	for range attempts {
		err = ForceUnmount(m)
		if err == nil {
			return err
		}

		<-time.After(time.Millisecond * 500)
	}
	return fmt.Errorf("unmount %s failed after 10 seconds of trying", m.MountPoint())
}

View on GitHub (pinned to 329838acdf)

Solutions

1. Run on Linux (fusermount3/fusermount) or macOS (diskutil) where unmount is implemented
2. On unsupported platforms, avoid ForceUnmount and use the mount server's own Unmount() (go-fuse) instead
3. Guard code paths with runtime.GOOS checks so forced unmounts are only attempted on supported systems

Example fix

// before
err := mount.ForceUnmountManyTimes(m, 10)
// after
if runtime.GOOS != "linux" && runtime.GOOS != "darwin" {
    err = m.Unmount() // go-fuse server unmount, portable
} else {
    err = mount.ForceUnmountManyTimes(m, 10)
}

switch runtime.GOOS {
case "linux", "darwin":
    // safe to call UnmountCmd
default:
    // do not call; use m.Unmount() or skip
}

When it happens

Trigger: Calling ForceUnmount/UnmountCmd on a GOOS that lacks a dedicated case (e.g. windows, freebsd, openbsd) — any forced-unmount attempt at runtime on an unsupported platform.

Common situations: Running kubo FUSE mount tests or auto-unmount logic on an OS without fusermount/diskutil support; cross-platform code assuming Linux semantics.

Related errors

• not mounted
• umount timeout
• unmount %s failed after 10 seconds of trying
• mountFuse: GetConfig() failed: %s
• mountFuse: ConstructNode() failed: %s

AI-assisted analysis of ipfs/kubo@329838acdf (2026-09-03). Data as JSON: /api/errors/298d2dde05af947f. Report an issue: GitHub.