# GrainDirectoryOptions.GetPartitionBoundaries

[Type overview](/orleans/docs/api/csharp/microsoft.orleans.runtime/orleans.configuration.graindirectoryoptions/) | [Properties](/orleans/docs/api/csharp/microsoft.orleans.runtime/orleans.configuration.graindirectoryoptions/properties/)

[Source](https://github.com/dotnet/orleans/blob/fbe240c34e9a1389ca5ab2d52f292ed8749ea530/src/Orleans.Runtime/Configuration/Options/GrainDirectoryOptions.cs)

```csharp
public Func<SiloAddress, int, ImmutableArray<uint>> GetPartitionBoundaries
```

Gets or sets the function which returns directory partition boundaries for a silo and partition count. Each array index identifies a partition and its value is that partition's exclusive starting boundary.