---
title: VSock
description: Go SDK - VSock API reference
---

Expose a host Unix socket or local Windows named pipe to a sandbox over virtio-vsock. See [VSock](/networking/host-sockets) for guest connection details, platform support, and security considerations.

<Note>VSock routes are local-only and unavailable with the multi-tenant deployment profile.</Note>

## Typical flow

```go
sandbox, err := m.CreateSandbox(ctx, "worker",
    m.WithImage("alpine"),
    m.WithVsock(m.VsockRoute{
        HostSocket: "/run/host-api.sock",
        Port:       5000,
    }),
)
```

## Functions

### <span className="msb-recv" id="m-withvsock">m.</span><span className="msb-hn">WithVsock()</span>

```go
func WithVsock(routes ...VsockRoute) SandboxOption
```

Append one or more guest-to-host VSock routes to the sandbox configuration.

## VsockRoute

| Field | Type | Default | Description |
|-------|------|---------|-------------|
| `HostSocket` | `string` | — | Existing Unix socket or local Windows named-pipe path |
| `Port` | `uint32` | — | Guest-facing port on host CID `2` |
| `SocketType` | `VsockSocketType` | `""` (stream) | Stream or datagram message semantics |

Use `VsockSocketTypeDgram` for a datagram route. Datagram routes are unavailable on Windows. Host paths must be absolute, and each socket type and port pair must be unique.

## VsockSocketType

| Constant | Value | Description |
|----------|-------|-------------|
| `VsockSocketTypeStream` | `"stream"` | Reliable, ordered byte stream |
| `VsockSocketTypeDgram` | `"dgram"` | Best-effort messages with preserved datagram boundaries |