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load balancer
One address, many machines. It spreads requests and stops sending them to a dead one.
What is load balancer?
A load balancer sits in front of identical servers and picks one per request. Health checks pull a bad instance out of rotation. Sticky sessions pin a user to one machine — useful, and a trap if that machine holds the only copy of their state.
Why does load balancer matter when vibe coding?
Models “scale” by making the server faster, or they put session state in memory and then add a second instance that cannot see it. Name the balancer and say where state lives.
How do you do load balancer?
Stateless app servers behind a balancer. Session and uploads live in a shared store. Health check hits a real ready route. Do not pin everyone to one box unless you must.
How do you ask a model for load balancer?
Put (service) behind a load balancer. Servers are stateless. Session and files live in a shared store. Unhealthy instances leave rotation. Do not keep user state only in process memory.
What goes wrong with load balancer?
A balancer in front of one server “for later.” You added a hop and no capacity. Add it when the second instance exists.