hashicorp/nomad · error

failed to configure container(%s): %v

Error message

failed to configure container(%s): %v

What it means

Launch wraps any failure from l.newLibcontainerConfig(command) with this error, prefixing the executor/container id. newLibcontainerConfig builds the libcontainer Config (namespaces, mounts, cgroups, capabilities, device rules) from the ExecCommand; a problem anywhere in that construction surfaces here with the original error appended as %v.

Source

Thrown at drivers/shared/executor/executor_linux_cgo.go:198

	return fmt.Errorf("orphaned processes %v have not been removed from cgroups pid file", orphanedPIDs)
}

// Launch creates a new container in libcontainer and starts a new process with it
func (l *LibcontainerExecutor) Launch(command *ExecCommand) (*ProcessState, error) {
	l.logger.Trace("preparing to launch command", "command", command.Cmd, "args", strings.Join(command.Args, " "))

	if command.Resources == nil {
		command.Resources = &drivers.Resources{
			NomadResources: &structs.AllocatedTaskResources{},
		}
	}

	l.command = command

	// A container groups processes under the same isolation enforcement
	containerCfg, err := l.newLibcontainerConfig(command)
	if err != nil {
		return nil, fmt.Errorf("failed to configure container(%s): %v", l.id, err)
	}

	if err := l.cleanOldProcessesInCGroup(containerCfg.Cgroups.Path); err != nil {
		return nil, err
	}

	container, err := libcontainer.Create(path.Join(command.TaskDir, "../alloc/container"), l.id, containerCfg)
	if err != nil {
		return nil, fmt.Errorf("failed to create container(%s): %v", l.id, err)
	}
	l.container = container

	// Look up the binary path and make it executable
	taskPath, hostPath, err := lookupTaskBin(command)
	if err != nil {
		return nil, err
	}
	if err := makeExecutable(hostPath); err != nil {

View on GitHub (pinned to 482b49bf1a)

Solutions

1. Read the wrapped %v suffix — it names the actual config step that failed (often 'configureCgroups: ...')
2. Ensure the task has a stats cgroup allocated (command.StatsCgroup() non-empty) when ResourceLimits is enabled
3. Validate the task's driver config (mounts, namespaces, capabilities) against supported values for your kernel
4. Confirm the host supports the required cgroups/namespaces (cgroup v2 vs v1 setup for Nomad)

cmd := &executor.ExecCommand{ /* ... */ }
if cmd.ResourceLimits && cmd.StatsCgroup() == "" {
    return fmt.Errorf("ResourceLimits requires a stats cgroup")
}
// also validate mounts/namespaces/capabilities against kernel support before Launch

if _, err := executor.Launch(cmd); err != nil && strings.Contains(err.Error(), "failed to configure container") {
    log.Printf("container config invalid: %v", err) // suffix names the failing step
}

When it happens

Trigger: newLibcontainerConfig fails: configureCgroups error (ErrCgroupMustBeSet), invalid namespaces/capabilities config, mount setup failure (e.g. /dev, /proc), or an invalid device/cgroup path derived from the command.

Common situations: Task launched without an allocated stats cgroup while ResourceLimits=true; malformed driver task config (bad cgroup path, unknown namespace); kernel lacking required namespaces/cgroups (e.g. no cgroup v2 support configured); missing device rules for the task.

Related errors

• configureCgroups: %w
• error setting up exec subcommand: %w
• ErrCgroupMustBeSet
• unable to get orphaned task PIDs: %v
• unable to send signal to process %d: %v

AI-assisted analysis of hashicorp/nomad@482b49bf1a (2026-09-04). Data as JSON: /api/errors/2a024b526c89cccb. Report an issue: GitHub.