> ## Documentation Index
> Fetch the complete documentation index at: https://docs.driver.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Node reuse

> nodeId runs a session on the machine that served an earlier one. Rarely needed; overrides country and type.

Every session response includes `servedBy`, the id of the machine that ran it. Pass it as `nodeId` on a later create to land on the same machine.

<CodeGroup>
  ```typescript TypeScript theme={"dark"}
  const first = await createSession({ country: "US" });
  // … work, stop …
  const again = await createSession({ nodeId: first.servedBy });
  ```

  ```python Python theme={"dark"}
  first = create_session(country="US")
  # ... work, stop ...
  again = create_session(nodeId=first["servedBy"])
  ```
</CodeGroup>

## When it helps

* A site keyed something to the machine. Rare; most keying is by cookies, which [profiles](/docs/options/profiles) handle better.
* Reproducing a problem that only happens on one machine.

## Rules

* `nodeId` overrides `country` and `type`. You get that machine, wherever it is.
* If the machine is busy or gone, the request fails. No fallback to another machine.

For most workloads leave `nodeId` out and let placement pick a machine in the country you asked for.