# Open a byte stream to a port inside a sandbox, over WebSocket: what SSH, SCP and port forwarding use

`GET /v1/sandboxes/{sandbox}/tunnel`

**In this build:** Works on the simulator or a real VM.

**Scope:** `ssh`

**CLI:** `harebox tunnel`

## Query

`port`

## Response: 200

Server-sent events. Each event's `id` is a resume cursor. Send `Upgrade: websocket` for WebSocket framing.

Errors follow [one format](../errors.html).