I use powetop on laptops to recommend config optimizations, it could run on a server too.
hdparm can configure HDDs to powerdown, but I’ve never had any success using it on my router.
In theory I think You could use WoL and have your router wake a device before sending traffic but I haven’t seen any guides for doing this so maybe I’m missing something.


What’s the timeout on a TCP connect?
Could you not wake from suspend in that window? Maybe even a full hibernate?