slackhq/nebula · error

Error creating interface: %w

Error message

Error creating interface: %w

What it means

Wrapping error in CreateTUNWithRequestedGUID (Windows): wintun.CreateAdapter failed to create or open the Wintun adapter with the requested name/GUID. Typical causes: the Wintun driver is not installed, insufficient privileges (driver load needs admin), or a stale conflicting adapter; the HRESULT is preserved via %w.

Source

Thrown at wintun/tun.go:73

//go:linkname procyield runtime.procyield
func procyield(cycles uint32)

//go:linkname nanotime runtime.nanotime
func nanotime() int64

// CreateTUN creates a Wintun interface with the given name. Should a Wintun
// interface with the same name exist, it is reused.
func CreateTUN(ifname string, mtu int) (Device, error) {
	return CreateTUNWithRequestedGUID(ifname, WintunStaticRequestedGUID, mtu)
}

// CreateTUNWithRequestedGUID creates a Wintun interface with the given name and
// a requested GUID. Should a Wintun interface with the same name exist, it is reused.
func CreateTUNWithRequestedGUID(ifname string, requestedGUID *windows.GUID, mtu int) (Device, error) {
	wt, err := wintun.CreateAdapter(ifname, WintunTunnelType, requestedGUID)
	if err != nil {
		return nil, fmt.Errorf("Error creating interface: %w", err)
	}

	tun := &NativeTun{
		wt:     wt,
		name:   ifname,
		handle: windows.InvalidHandle,
	}

	tun.session, err = wt.StartSession(0x800000) // Ring capacity, 8 MiB
	if err != nil {
		tun.wt.Close()
		return nil, fmt.Errorf("Error starting session: %w", err)
	}
	tun.readWait = tun.session.ReadWaitEvent()
	return tun, nil
}

func (tun *NativeTun) Name() (string, error) {

View on GitHub (pinned to dd8f660c0a)

Solutions

1. Install/update the Wintun driver
2. Run nebula with administrator privileges
3. Remove a stale adapter with the same name and retry
4. Check the wrapped HRESULT for the exact failure

When it happens

Trigger: Thrown at wintun/tun.go:73 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of slackhq/nebula@dd8f660c0a (2026-09-03). Data as JSON: /api/errors/372695ec8f4f0efc. Report an issue: GitHub.