# TestCluster.StartAdditionalSilosAsync(int, bool, CancellationToken)

[Type overview](/orleans/docs/api/csharp/microsoft.orleans.testinghost/orleans.testinghost.testcluster/) | [Methods](/orleans/docs/api/csharp/microsoft.orleans.testinghost/orleans.testinghost.testcluster/methods/)

[Source](https://github.com/dotnet/orleans/blob/1644940b035c7bdf215a4fd7135757c06bcfe9ec/src/Orleans.TestingHost/TestCluster.cs)

```csharp
public Task<List<SiloHandle>> StartAdditionalSilosAsync(int silosToStart, bool startAdditionalSiloOnNewPort, CancellationToken cancellationToken)
```

Start a number of additional silos, so that they join the existing cluster.

### Parameters

- `silosToStart` (`int`): Number of silos to start.
- `startAdditionalSiloOnNewPort` (`bool`): Whether to start each silo on a new port.
- `cancellationToken` (`CancellationToken`): The token used to cancel silo startup.

### Returns

List of silo handles for the newly started silos.