You're on-call, and a critical microservice responsible for user authentication is experiencing a complete outage during peak business hours, impacting all users. The primary monitoring dashboards are also unresponsive. Describe your immediate actions, how you would triage the situation without your usual tools, and what communication strategy you would employ to keep stakeholders informed under extreme pressure.
final round · 5-7 minutes
How to structure your answer
MECE Framework: 1. Establish Communication: Immediately notify on-call lead/manager via alternative channels (SMS, direct call). Create a dedicated incident bridge (Slack/Teams channel, conference call). 2. Initial Assessment (Manual): Attempt direct SSH/console access to known authentication service hosts. Check basic network connectivity (ping, traceroute) to service IPs. Verify load balancer status/health checks. 3. Hypothesize & Isolate: Based on connectivity, assume network, host, or application layer failure. Prioritize network/host issues first due to monitoring outage. 4. Remediate (Manual): Attempt service restarts on suspected hosts. If host-level, try reboot. 5. Restore Monitoring: Work to bring up secondary/backup monitoring tools or access logs directly from hosts. 6. Communicate: Provide frequent, concise updates on status, actions, and estimated time to resolution (ETR) to stakeholders.
Sample answer
My immediate actions would follow a modified CIRCLES framework for incident response. First, I'd Communicate: immediately notify my on-call lead and key stakeholders via alternative channels (SMS, direct call) and establish a dedicated incident bridge (e.g., Slack channel, emergency conference line). Next, I'd Investigate without dashboards: attempt direct SSH/console access to known authentication service instances and underlying infrastructure (e.g., Kubernetes nodes, EC2 instances). I'd manually check basic network connectivity (ping, traceroute), process lists (ps aux), and recent logs (journalctl, tail -f /var/log/auth.log) on those hosts. My goal is to Root cause rapidly. If host-level issues are suspected (e.g., high CPU/memory), I'd prioritize a restart of the service or even the host. I'd then Communicate frequent, concise updates on status, actions taken, and estimated time to resolution (ETR) to the incident bridge. Once service is restored, I'd Learn from the incident, ensuring monitoring is restored and a post-mortem is scheduled to prevent recurrence and improve resilience.
Key points to mention
- • Prioritization of direct access and command-line tools when primary monitoring fails.
- • Systematic triage approach (e.g., network -> infrastructure -> application -> dependencies).
- • Proactive and frequent communication strategy under pressure, even with limited information.
- • Understanding of potential immediate mitigation steps (restart, rollback, failover).
- • Recognition of the critical impact of an authentication service outage.
Common mistakes to avoid
- ✗ Panicking and not following a structured approach.
- ✗ Spending too much time trying to fix monitoring before addressing the core outage.
- ✗ Failing to communicate frequently or clearly, leading to increased stakeholder anxiety.
- ✗ Making changes without understanding potential side effects or having a rollback plan.
- ✗ Not involving other team members or escalating appropriately when stuck.