how to configure multi server?

I want use this to store data in multi server,but always just store in one

is that need some code to config?

I just add a config in appsettings.json

```
"Memcached": {
    "Servers": [
      {
        "Address": "39.108.125.154",
        "Port": 11211
      },
      {
        "Address": "39.108.125.154",
        "Port": 11210
      }
    ]
  }
}
```