How do you troubleshoot a complex technical issue in a production environment?

This question assesses your problem-solving abilities, particularly in high-pressure situations involving technical issues. Key points to consider include: 1) identifying the scope and nature of the problem; 2) gathering data and relevant information; 3) forming hypotheses and testing them; 4) involving stakeholders if necessary; 5) documenting the process and learnings. Articulate your thought process clearly, demonstrating both technical knowledge and analytical skills.

In a situation where a web application went down in production, my first step would be to check the error logs and monitoring alerts to get a preliminary understanding of the issue. After identifying that the server had run out of memory, I would then analyze our current usage patterns to ascertain whether it was a temporary spike or a deeper issue. I’d investigate possible memory leaks in the code and run performance profiling tools to confirm my hypothesis. If necessary, I would scale the server resources while working on a more permanent code fix and ensure all stakeholders are kept informed throughout the process.

Once, when I encountered a complex issue with a database where queries were timing out, I first gathered relevant metrics and logs to diagnose the problem. I noticed that the load was significantly higher than usual, so I checked for any recent changes in the application or infrastructure that might have contributed to the bottleneck. After identifying that a new reporting feature was causing excessive loads, I proposed optimizing the queries and implementing caching mechanisms. Throughout this process, I communicated regularly with the team to ensure alignment on the resolution steps and next actions, ultimately restoring normal operation while documenting our findings for future reference.