← IXL Learning Interview Insights
I started with kubectl describe and logs which felt right, but I fumbled a bit when they pushed on init-container failures specifically.
Start by describing a systematic, layered debugging approach that moves from the pod's status and events to logs, configuration, and finally the node or cluster level. Emphasize using kubectl commands to gather evidence at each layer and forming hypotheses to test. Conclude by explaining how you would fix the root cause and prevent recurrence.
Pro tip: Mention that you always check the pod's restart count and last termination reason first, as this often immediately points to the root cause (e.g., OOMKilled, CrashLoopBackOff). Also, highlight the importance of checking events and logs from the previous container instance using --previous.
Use kubectl describe pod to see the pod's status, restart count, and recent events. Look for clues like OOMKilled, CrashLoopBackOff, or scheduling issues.
Retrieve logs from the current and previous container instances using kubectl logs and --previous. Look for application errors, stack traces, or startup failures.
Review the pod's YAML for misconfigurations (e.g., wrong image, missing env vars, resource limits). Check if dependent services (DB, API) are reachable and healthy.
Reproduce the issue locally or in a staging environment. Try running the container with a shell to debug interactively. Adjust resource limits or configuration to see if the crash persists.
Apply the fix (e.g., increase memory, correct config) and verify the pod stabilizes. Add monitoring, alerts, or health checks to catch similar issues early.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.
Covered liveness, readiness, startup probes.
Start by defining the three main probe types (liveness, readiness, startup) and their purposes, then explain how each affects traffic routing and deployment behavior. Use concrete examples of misconfigurations and their consequences to demonstrate practical understanding.
Pro tip: Emphasize that readiness probes control traffic routing by removing pods from service endpoints, while liveness probes trigger restarts—confusing these is a common pitfall that can cause outages during deployments.
Briefly explain liveness, readiness, and startup probes, including their primary goals and how they differ.
Describe how readiness probes determine whether a pod receives traffic by adding/removing it from service endpoints.
Discuss how liveness and startup probes affect pod lifecycle, restarts, and rolling updates, including failure scenarios.
Give concrete examples of correct and incorrect configurations, highlighting trade-offs like probe timing and thresholds.
Conclude with best practices for setting probes in production, such as using startup probes for slow-starting apps.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.