hashicorp/nomad · critical

not implemented

Error message

not implemented

What it means

mountDir is a stub that unconditionally panics with 'not implemented'. Bind-mounting directories is only supported on Linux; on other platforms this placeholder is the entire implementation, so any call to it crashes. It exists only so the package compiles on non-Linux GOOSes.

Source

Thrown at client/allocdir/fs_default.go:12

// Copyright IBM Corp. 2015, 2026
// SPDX-License-Identifier: BUSL-1.1

//go:build !linux

package allocdir

import "os"

// mountDir bind mounts old to next using the given file mode.
func mountDir(old, next string, uid, gid int, mode os.FileMode) error {
	panic("not implemented")
}

View on GitHub (pinned to 482b49bf1a)

Solutions

1. Run the client on Linux where the real bind-mount implementation is built
2. Avoid code paths that require mount support when targeting non-Linux platforms
3. Skip/exclude allocdir mount tests on non-Linux GOOS with a build-tag guard
4. Contribute or vendor a platform-specific implementation if non-Linux support is required

Example fix

// before
mountDir(old, next, uid, gid, mode) // panics on this platform
// after
if runtime.GOOS != "linux" {
	return fmt.Errorf("mountDir is not supported on %s", runtime.GOOS)
}
mountDir(old, next, uid, gid, mode)

if runtime.GOOS != "linux" {
	return fmt.Errorf("directory mounting requires Linux, running on %s", runtime.GOOS)
}
// proceed to call allocdir mount APIs only on Linux

// Go: recover around mount operations on non-Linux builds
func safeMount(old, next string, uid, gid int, mode os.FileMode) (err error) {
	defer func() {
		if r := recover(); r != nil {
			err = fmt.Errorf("mountDir unsupported: %v", r)
		}
	}()
	mountDir(old, next, uid, gid, mode)
	return nil
}

When it happens

Trigger: Any call to mountDir while the non-Linux build of the allocdir package is compiled in — i.e., invoking allocdir mount functionality (e.g., during task environment setup with mount-enabled configs) on darwin/windows/BSD builds.

Common situations: Running or unit-testing a Nomad-like client on macOS/Windows; CI on non-Linux runners exercising allocdir code paths; enabling mount-related task driver options on an unsupported OS.

Related errors

• Failed to unmount proc %q: %w
• mount --make-rshared %s failed: %q
• mount --rbind %s %s failed: %q
• failed to bind mount ns at %s: %v
• journald log monitoring only available on linux

AI-assisted analysis of hashicorp/nomad@482b49bf1a (2026-09-04). Data as JSON: /api/errors/198ff678dbbdd73d. Report an issue: GitHub.