# Ports (/docs/devices/ports)



`warden port claim` leases TCP ports from a range so dev servers, Metro and test servers never collide across agents; use it whenever a script needs a port of its own.

```bash
warden port claim --from 8091 --span 20 --json
warden port release --mine
```

`port claim` leases free port(s) from `FROM..FROM+SPAN-1` and prints one port per line. Each candidate is bind-probed, so a port something else is already listening on is skipped even if it has no lease. Leases follow the same owner + liveness rules as devices.

| Flag               | Default |                             |
| ------------------ | ------- | --------------------------- |
| `--from <port>`    | `8091`  | first port of the range     |
| `--span <n>`       | `20`    | range size                  |
| `--count <n>`      | `1`     | how many ports              |
| `--ttl <duration>` | `30m`   | lease TTL without heartbeat |
| `--label <label>`  |         | shown in `warden port ls`   |

`warden port ls` lists port leases. `port release` takes `<port…>`, `--lease <id…>` or `--mine`, and only releases your own leases unless you pass `--force`.

## Dev servers [#dev-servers]

```bash
PORT=$(warden port claim --from 3000 --span 50) bun run dev
```