On-callEasyoc-g542

Subject Env misconfigLevel Entry–Mid~15 minCommon in Reliability & on-call interviewsIndustries Software development, Technology

Question

A service starts up fine after a deploy, but one feature — sending notification emails — silently stopped working. No errors in the main request path, no 500s, just no emails going out. The deploy moved the service to a new environment config. You suspect the email integration. Where do you look, and how do you confirm the cause?

What a strong answer looks like

Stop the bleeding first (mitigate), then form hypotheses from real signals. Separate root cause from symptom, communicate status as you go, and close with what prevents a repeat.

Learn the concepts

Diagram & narrate the incident

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Run or narrate your approach, then ask the coach.