hashicorp/nomad · error

path was not relative to the mount task path

Error message

path was not relative to the mount task path

What it means

getPathInMount resolves a binary located under a mount by relating the bin path to the mount's task-side path. If filepath.Rel(mountTaskPath, bin) fails or is empty, the bin was not under the mount's task path and this error is thrown.

Source

Thrown at drivers/shared/executor/executor_linux_cgo.go:1077

	// Turn relative-to-taskdir path into re-rooted absolute path to avoid
	// libcontainer trying to resolve the binary using $PATH.
	// Do *not* use filepath.Join as it will translate ".."s returned by
	// filepath.Rel. Prepending "/" will cause the path to be rooted in the
	// chroot which is the desired behavior.
	return filepath.Clean("/" + rel), hostPath, nil
}

// getPathInMount for the binary in the mount's host path, constructing the path
// considering that the bin path is rooted in the mount's task path and not its
// host path. It returns the absolute path rooted inside the container and the
// absolute path on the host.
func getPathInMount(mountHostPath, mountTaskPath, bin string) (string, string, error) {

	// Find the path relative to the mount point in the task so that we can
	// trim off any shared prefix when we search on the host path
	mountRel, err := filepath.Rel(mountTaskPath, bin)
	if mountRel == "" || err != nil {
		return "", "", fmt.Errorf("path was not relative to the mount task path")
	}

	hostPath := filepath.Join(mountHostPath, mountRel)

	err = filepathIsRegular(hostPath)
	if err != nil {
		return "", "", err
	}

	// Turn relative-to-taskdir path into re-rooted absolute path to avoid
	// libcontainer trying to resolve the binary using $PATH.
	// Do *not* use filepath.Join as it will translate ".."s returned by
	// filepath.Rel. Prepending "/" will cause the path to be rooted in the
	// chroot which is the desired behavior.
	return filepath.Clean("/" + bin), hostPath, nil
}

// filepathIsRegular verifies that a filepath is a regular file (i.e. not a

View on GitHub (pinned to 482b49bf1a)

Solutions

1. Ensure the command binary resides under the declared mount's task path
2. Fix the mount definitions (task path vs host path) in the job/driver config
3. Verify paths are clean/absolute and consistently formatted
4. Check host volume/CSI mount options so the mount actually contains the binary

Example fix

// before
command = "/opt/bin/app"  # not under mounted local/
mounts = [{ task_path = "local", host_path = "/srv/share" }]
// after
command = "local/app"  # or place binary inside the mount

if !strings.HasPrefix(bin, mount.TaskPath) {
    return fmt.Errorf("bin %q not under mount task path %q", bin, mount.TaskPath)
}

if err != nil && strings.Contains(err.Error(), "not relative to the mount task path") {
    // bin lives outside this mount; adjust mounts or command path
    return fmt.Errorf("mount/command mismatch: %w", err)
}

When it happens

Trigger: lookupTaskBin iterates task mounts; for each mount whose task path should prefix the bin, if bin is not beneath mountTaskPath (or paths are inconsistent), this error is returned for that mount.

Common situations: Binary lives outside the mount being searched; mount task path configured differently between host and task views (custom CSI/host volume mounts); typo'd mount definitions in the driver config; path casing/trailing-slash inconsistencies.

Related errors

• failed to determine relative path base=%q target=%q: %v
• ErrCgroupMustBeSet
• user name must contain domain
• failed to resolve alloc directory: %w
• failed to resolve requested path: %w

AI-assisted analysis of hashicorp/nomad@482b49bf1a (2026-09-04). Data as JSON: /api/errors/06871247baca75d8. Report an issue: GitHub.