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

# Connect From a Fly App

<Warning>
  Important: We are not able to provide support or guidance for unmanaged Postgres. We now offer [Fly.io Managed Postgres](/mpg) , our fully-managed database service that handles all aspects of running production PostgreSQL databases.
</Warning>

Connection string URIs are a common way to describe a connection to a Postgres server. The output from `flyctl postgres create` provides a connection string of the format:

```
postgres://{username}:{password}@{hostname}:{port}/{database}?options
```

Fly Postgres is an app that belongs to your Fly organization. The `hostname` in this string resolves to an internal IPv6 address that can be reached by any of your apps that live in the same [IPv6 private network](/networking/private-networking).

You can give this connection string to another Fly app by passing it as a secret, or by [Attaching](/postgres/managing/attach-detach) it.