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liveness and readiness
Liveness: the process is not stuck, so restart it. Readiness: it can take traffic, so leave it out of the balancer until it can.
What is liveness and readiness?
A liveness probe failure means kill and restart. A readiness probe failure means stop sending requests, but do not restart. Mixing them makes a database blip kill every pod, which then all restart and stampede back.
Why does liveness and readiness matter when vibe coding?
Models expose one `/health` that checks the database and wire it as liveness. The database hiccups, every instance restarts, and the hiccup becomes an outage. Split the probes.
How do you do liveness and readiness?
Liveness is local: the event loop is scheduling. Readiness includes dependencies you refuse to serve without. Neither probe should be expensive or recursive.
How do you ask a model for liveness and readiness?
Split health checks. Liveness only proves the process is not deadlocked — do not check the database there. Readiness fails when (dependency) is down, and the load balancer stops routing. Do not restart on readiness failure.
What goes wrong with liveness and readiness?
A readiness check that calls yourself through the public URL. The probe depends on the thing it is probing.