Q: How would you design monitoring for a new microservice?
Instrument RED metrics (rate, errors, duration). Add resource metrics (CPU, memory). Create a dashboard with SLO status. Set up alerts on SLO burn rate. Ensure logs are structured.
Q: A service is slow but CPU and memory look fine. How do you debug?
Check downstream dependencies. Look at traces to find the slow span. Check database query latency. Look for lock contention or connection pool exhaustion.
Q: How do you handle log volume at scale?
Sample verbose logs. Use log levels appropriately. Aggregate at the edge. Set retention policies.