As of the end of SGA2, all sites participating in the Fenix project have federated their OpenStack resources in the Fenix AAI. It is now possible to access any of the services and select authentication through the Fenix AAI. This will in turn take the user to the selected origin Identity Provider (IdP) for authentication.
The video below details an example of the OpenStack web federation. A simple use case is shown, connecting to three different OpenStack platforms at CSCS, Juelich, and CINECA. In addition, how to connect to an instance on the Juelich OpenStack through SSH is demonstrated, thus mimicking the example of a user with different instances on different OpenStack platforms.

A demo video can be found here: https://drive.google.com/file/d/1riJww9Lm8QUVC6ujoQeEJUa0xjNLleHH/view