Fleet management
Also called: multi-device management, centralized device management
Fleet management is administering several machines from one place — seeing their status, pushing updates, and running commands across all of them.
Fleet management means operating more than one machine as a group rather than logging into each one.
At minimum it needs: an inventory of what exists, live status for each device, a way to push updates safely, and a way to run a command across a selection. Useful additions are per-device cost and resource tracking, and an audit trail of who did what.
This is the gap in the consumer appliance category. Home-server operating systems are built around a single box; running five means five browser tabs and five upgrade decisions. Teams that need more usually leave the appliance world entirely for Proxmox clusters plus Ansible, trading ease of setup for manageability.
deputyOS treats multi-device administration as a first-class feature rather than something you graduate to.