One rented machine, a free hypervisor, and as many virtual machines as the hardware will hold. How to budget RAM, lay out ZFS, get networking right on a data-centre switch port — the part that differs from a homelab — and keep the backups off the box.
What you can rent is not this year's Xeon against this year's EPYC but an eight-year spread of generations at prices seven times apart. Per-core speed, memory bandwidth, PCIe lanes and price per core — and which of those differences your workload can actually feel.
The port is the easy part — it is lit in an afternoon. Then the machine behind it has to produce 12.5 gigabytes every second, and each layer between the disk and the wire gets a chance to be the reason it does not. The arithmetic, in the order it fails.
Renting turns hardware into a monthly line item; colocating turns it back into an asset with jobs attached. The technical difference is small, the financial one decides everything. Build both sides over three years — and cost your own engineer's time honestly.
One exit node is easy to specify and tells you nothing about the next fifty. Concurrency, throughput per session and oversubscription set subscribers per node; packet rate rather than cipher choice sets the ceiling; and country coverage wants a tiered fleet, not identical boxes.
No one can quote a player count without knowing the title, but the shape of the limit is knowable. The tick deadline binds first, memory decides instances per box, and bandwidth binds the fleet rather than the instance. Each has arithmetic you can run on your own numbers.
A shared slot and a dedicated node can cost the same per terabyte and behave nothing alike. Contended random IO, fair-use ceilings and shared address reputation are what separate them — along with everything a slot simply cannot run.
A virtual machine is a slice of a box; a dedicated server is the box. The useful question is where the slice stops being enough. Four ceilings decide it — single-thread speed, disk latency, packet rate and RAM — and an afternoon of measurement settles it better than a year of guessing.
The machine is the easy part. Address reputation, geolocation and an abuse process that answers decide whether the service works at all — then conntrack, MSS clamping and IPv6 decide whether it scales past one node.
A game server is a simulation loop with a fixed deadline, and no amount of cores makes one thread finish sooner. What to buy for a single instance, what to buy for density, and why jitter beats port size.
The edges take the load until a purge, a deploy or a cold region sends every one of them to the origin at once. Hit-ratio arithmetic, the cache headers that are the whole contract, and which machine to actually build.
A broken AAAA record does not take a site down, it makes it slower for everyone who has IPv6. The prefix you get, the static configuration to prefer, the three things that break it, and how to prove it works.