I have an old ThinkPad 11e running Debian that I have repurposed into a home server. It’s only supposed to run TVheadend. I don’t need any other services for now, but later on i might add a few using docker.
Is it enough to set multiuser.target as default to disable gui and keep the system always on?
How can I disable all unnecessary services and minimize power usage?
Depends. Usually it is still good as a UPS for a few minutes, and some laptops have a bios option to limit full charge which lowers the risk even further.
And how much need is there for a UPS in this scenario - realistically.
Some of the people here take their admin-LARPing a tad too seriously. Most households have reliable enough electricity, and even if there’s an outage once every quarter, would a dead battery even help?
I advocate for being realistic with one’s own needs. Don’t build a five-nines datacenter for a glorified weather station or VCR.
That is why I said it depends. There are many places where electricity cuts for a short duration are quite frequent. Often you don’t even notice it, but a 24/7 server would be effected.
In general, I think the risk of laptop batteries catching fire is overstated especially if you limit the charge to 80% or so. So weighting these two issues against each other you can come out either way, but I think for most places it will come down towards a UPS being nice to have.
Everything has pros and cons. I’ve seen 3 laptops (of my family) with batteries that looked like a baloon after several years. I’ve subsequently removed or replaced them. I’d definitely check on them every now and then. A UPS is nice. Burning down a house isn’t. I haven’t seen them catch on fire (yet), they supposedly have at least some protection. But definitely get them out of the laptop once they’re dead anyways or don’t look alright. Everyone is responsible to make that decision on their own. Take care.
Worth taking a look at the battery - especially an old one on a repurposed device - before considering it safe. Spicy pillows happen.