You are incident commander for a total outage. It is 2am, 6 engineers are online, and nobody knows the cause. What do you do?
What they are really testing: Incident leadership, not debugging skill. They want structure, communication and the discipline to keep people from making uncoordinated changes.
A real interview question
You are incident commander for a total outage. It is 2am, 6 engineers are online, and nobody knows the cause. What do you do?
What most people say
drag me
“Get everyone looking at logs and dashboards to find the root cause as fast as possible.”
Six people investigating in parallel with no coordination is the classic failure: duplicated work, conflicting changes applied simultaneously, nobody talking to stakeholders, and no record of what was tried.
The follow-ups they ask next
An executive joins the call and starts directing engineers. How do you handle it?
Redirect politely and firmly: acknowledge them, offer a dedicated update channel, and keep technical direction with the commander. Split authority during an incident is dangerous.
What makes a postmortem blameless in practice, not just in name?
Focus on the conditions that made the error reasonable: what did the person see, what did the tooling allow. Actions target systems and guardrails, not people or "be more careful".
What the interviewer is listening for
- Assigns roles and does not debug personally
- Mitigates before diagnosing
- Plans handover and communicates on cadence
What sinks the answer
- Commander joins the debugging
- Parallel uncoordinated changes
- No stakeholder communication
If you genuinely do not know
Say this instead of freezing. Reasoning out loud from what you do know beats silence every single time, and a good interviewer is listening for exactly that.
“I [command rather than debug]: state roles, [one comms owner, assigned investigation areas]. Then [mitigate first, rollback or failover or shed traffic]. Enforce [one announced change at a time so effects are attributable], keep [a timestamped timeline], update stakeholders [every 30 minutes even with no news], and [plan handover before fatigue].”
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