I’m thinking about buying a Raspberry Pi to start my self-hosted journey. I have three usecases in mind: Navidrome server, Jellyfin server and a Pi-hole network ad-blocking. Can a single machine (like a Raspberry Pi) run these operations simultaneously? Thanks in advance!


As other commenters have said yes you can run these depending on the Pi. Do note however if you need transcoding, A Pi is not recommended by jellyfin:
https://jellyfin.org/docs/general/administration/hardware-selection#potentially-problematic-hardware