Copying data is solved; sequencing is what fails. Lower the TTL two days out, sync in two passes so the window moves only a delta, replicate rather than copy databases, and rehearse the whole cutover once a week early. Plus the six things that always break.
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 streaming server does three jobs with three different bottlenecks. Ingest wants path quality, transcode wants cores, egress wants a port. Size them separately, work a real build end to end, and see why the blended ABR bitrate — not the top rung — sets the uplink.
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.
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.
A stock kernel moves a few gigabits and then flattens. The bandwidth-delay arithmetic behind it, the sysctl ceilings to raise, the NIC queue work that follows, and the nginx settings that stop copying bytes.
The first fifteen minutes after handover: a real user account, key-only SSH, a firewall that defaults to closed, and updates that install themselves.