Post: #3

unfortunately the best solution is not the same for all servers because every server have its own scenario. Many years ago the only option was rent overpriced dedicated server because on this age the only hosting plans available are webhostings and dedicated hostings

but now with the cloud revolution on IT/hosting, everyone can find an cheap cloud. If your have an small shard, any cloud server with 1.0GHz single core CPU and 2gb ram will be enough. You will only need something better if your shard is getting bigger or if you have some retarted ppl making DDoS attacks on your server, making it consume more RAM. Anyway, there's no OS preference, both linux and windows are able to run sphere, windows is much easier to setup but its paid, and linux is a hell to do the first setup but its free

you must also take really care with bandwidth costs. On huge clouds like AWS / Azure / Google Cloud / etc you doesn't have to pay incoming bandwidth but the outgoing bandwidth is paid. Or you can also find some reseller cloud hostings that are not so good as these huge clouds but usually they offer an fixed bandwidth limit per month and if you reach this limit they will shutdown your server instead keep it online making you pay this extra cost. So some ppl prefer the freedom of these huge clouds, some others prefer stay on the safe line with an reseller hosting with fixed price that won't bring surprises on the monthly bill. Each hosting company have its own contract so you must always read it first to prevent future problems