# addMongoDBReplicaSet

- Module: [Aspire.Hosting.MongoDB](/reference/api/typescript/aspire.hosting.mongodb.md)
- Version: `13.6.0`
- Kind: `method`
- Source: [GitHub](https://github.com/microsoft/aspire/tree/f4c27f2d43ddc1cacd0dd083b30d1fea1cee7a62)

Adds a MongoDB replica set resource to the application model.

## Definition

```typescript
interface IDistributedApplicationBuilder {
  // ... omitted for brevity
  addMongoDBReplicaSet(
    name: string,
    userName?: ParameterResource,
    password?: ParameterResource): MongoDBReplicaSetResource
}
```

## Parameters

- `name` (`string`)
- `userName` (`ParameterResource`) `optional`
- `password` (`ParameterResource`) `optional`

## Returns

[MongoDBReplicaSetResource](/reference/api/typescript/aspire.hosting.mongodb/mongodbreplicasetresource.md) `builder`

## Applies to

- [IDistributedApplicationBuilder](/reference/api/typescript/aspire.hosting.mongodb/idistributedapplicationbuilder.md)