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Hands-on Lab·Certified Kubernetes Administrator

Probes and Pod Lifecycle

Three probes that look similar and do entirely different things: one gates traffic, one restarts the container, one buys time at startup. Then the other end of the lifecycle, where a preStop hook and SIGTERM decide whether shutdown drops requests.

Configuration and Secrets Guide 36 of 103 Intermediate

Written against the versions above. Timings and restart counts depend on how long you wait. The probe semantics do not.

Any cluster does. Run against the four-node lab.
Server NameIP AddressOSRolesCPURAMHDD
CKA1001192.168.0.175Ubuntu 26.04 LTSControl Plane Node2 Core4 GB50 GB
CKA1001-NODE01192.168.0.176Ubuntu 26.04 LTSWorker Node2 Core4 GB50 GB
CKA1001-NODE02192.168.0.177Ubuntu 26.04 LTSWorker Node2 Core4 GB50 GB
CKA1001-NODE03192.168.0.178Ubuntu 26.04 LTSWorker Node2 Core4 GB50 GB

Before you start

  1. Three probes, three jobs

  2. Ready is a condition, not a status

  3. A failing liveness probe restarts the container

  4. Shutdown: preStop, then SIGTERM, then the grace period

  5. Clean up

Official sources