Readiness Gate - CI/CD Glossary Definition
A readiness gate holds an instance out of rotation until a required condition is met.
A readiness gate is a condition that must be satisfied before an instance or deployment is considered ready to receive traffic, letting a rollout wait on external signals.
Beyond a basic readiness probe, a readiness gate can require external state (such as a load balancer registering the instance) before traffic is routed, which prevents shifting load to a not-yet-ready target.
Where this shows up in a real pipeline
A definition is only useful if you can recognise the thing in your own logs. In practice this concept surfaces when a job behaves differently between a local run and a runner, which is where most CI debugging starts.
- Compare a local run against a CI run of the same command before assuming a tool is at fault.
- Runner environments differ in shell, PATH, TTY availability, available memory, and disk. Most CI-only behaviour traces to one of those five.
- Pin tool versions so an environment difference cannot be introduced by an unrelated update.
Frequently asked questions
What is Readiness gate?
A readiness gate is a condition that must be satisfied before an instance or deployment is considered ready to receive traffic, letting a rollout wait on external signals.