A curated list of the most commonly asked Microservices interview questions, ranging from beginner to advanced architecture and distributed systems topics.
- Fundamentals
- Architecture and Design
- Communication
- Data Management
- Distributed Systems
- Security
- Scalability and Performance
- Deployment and DevOps
- Observability
- Resilience and Reliability
- Testing
- Event-Driven Architecture
- Cloud and Kubernetes
- Java and Spring Boot
- Advanced and Difficult Questions
- What are microservices?
- What problems do microservices solve?
- Difference between monolith and microservices?
- Advantages of microservices?
- Disadvantages of microservices?
- When should you NOT use microservices?
- What are the characteristics of microservices?
- What is a bounded context?
- What is domain-driven design (DDD)?
- What is loose coupling?
- What is high cohesion?
- What is service autonomy?
- What is independent deployment?
- What is decentralized governance?
- What is decentralized data management?
- What is Conway’s Law?
- What is the strangler pattern?
- What is service decomposition?
- How do you identify service boundaries?
- What is the difference between SOA and microservices?
- What are design principles of microservices?
- What is API-first design?
- What is contract-first development?
- What is a hexagonal architecture?
- What is clean architecture?
- What is CQRS?
- What is event sourcing?
- What is a sidecar pattern?
- What is the ambassador pattern?
- What is backend-for-frontend (BFF)?
- What is API composition?
- What is aggregation pattern?
- What is database-per-service?
- Shared database vs database-per-service?
- What is anti-corruption layer?
- What is transactional outbox pattern?
- What is saga pattern?
- Choreography vs orchestration?
- What is service mesh?
- What is API Gateway?
- Synchronous vs asynchronous communication?
- REST vs gRPC?
- REST vs messaging?
- What is idempotency?
- What is eventual consistency?
- What are HTTP status codes?
- What is correlation ID?
- What is request tracing?
- What is service discovery?
- Client-side vs server-side discovery?
- What is load balancing?
- What is message broker?
- Kafka vs RabbitMQ?
- What is backpressure?
- What is retry mechanism?
- What is exponential backoff?
- What is dead-letter queue?
- What is circuit breaker?
- What is bulkhead pattern?
- What is timeout management?
- How is data managed in microservices?
- Why should each service own its database?
- SQL vs NoSQL in microservices?
- What is distributed transaction?
- Why are distributed transactions difficult?
- What is two-phase commit?
- Why is 2PC avoided in microservices?
- What is CAP theorem?
- What is BASE consistency?
- ACID vs BASE?
- What is data replication?
- What is sharding?
- What is read replica?
- What is cache-aside pattern?
- What is distributed caching?
- Redis use cases in microservices?
- What is schema evolution?
- What is data synchronization?
- How do you handle schema migration?
- How do you avoid data inconsistency?
- What makes distributed systems hard?
- What is network partition?
- What is split-brain problem?
- What is consensus?
- What is leader election?
- What is distributed locking?
- What is clock skew?
- What is distributed tracing?
- What is service registry?
- What is service heartbeat?
- What is quorum?
- What is eventual consistency in practice?
- What are distributed failures?
- What is failover?
- What is graceful degradation?
- What is chaos engineering?
- What is the fallacies of distributed computing?
- What is horizontal scaling?
- What is vertical scaling?
- How do microservices fail differently than monoliths?
- How do you secure microservices?
- What is OAuth2?
- What is OpenID Connect?
- JWT vs session authentication?
- What is mTLS?
- What is zero trust architecture?
- What is API security?
- What is rate limiting?
- What is API throttling?
- What is RBAC?
- What is ABAC?
- How do services authenticate each other?
- What is secret management?
- What is Vault?
- How do you secure Kafka?
- What is token propagation?
- What are common security vulnerabilities?
- What is OWASP?
- How do you secure communication channels?
- What is certificate rotation?
- How do microservices scale?
- Stateless vs stateful services?
- What is autoscaling?
- What is caching strategy?
- What is connection pooling?
- What is thread pool exhaustion?
- What is reactive programming?
- What is non-blocking I/O?
- What is performance bottleneck analysis?
- What is load shedding?
- What is request batching?
- What is asynchronous processing?
- What is high throughput architecture?
- What is low latency architecture?
- What is memory leak in microservices?
- How do you optimize startup time?
- What is cold start problem?
- How do you handle traffic spikes?
- What are performance anti-patterns?
- What metrics matter most?
- What is CI/CD?
- Blue-green deployment?
- Canary deployment?
- Rolling deployment?
- What is immutable infrastructure?
- What is Infrastructure as Code?
- What is Docker?
- Why are containers important?
- What is Kubernetes?
- What is Helm?
- What is service orchestration?
- What is configuration management?
- What is feature toggle?
- What is GitOps?
- What is deployment rollback?
- What is container orchestration?
- What is init container?
- What is sidecar container?
- What is liveness probe?
- What is readiness probe?
- What is observability?
- Logging vs monitoring vs tracing?
- What is centralized logging?
- What is distributed tracing?
- What is OpenTelemetry?
- What is Prometheus?
- What is Grafana?
- What are golden signals?
- What are SLIs, SLOs, and SLAs?
- What is alert fatigue?
- What is structured logging?
- What is log correlation?
- What metrics should each service expose?
- What is health check endpoint?
- What is tracing propagation?
- What is span?
- What is trace sampling?
- What is root cause analysis?
- What is anomaly detection?
- What are observability best practices?
- How do you build resilient microservices?
- What is retry storm?
- What is cascading failure?
- What is resilience testing?
- What is fault tolerance?
- What is disaster recovery?
- What is multi-region deployment?
- What is active-active architecture?
- What is active-passive architecture?
- What is self-healing infrastructure?
- What types of testing are used in microservices?
- What is contract testing?
- What is consumer-driven contract testing?
- What is integration testing?
- What is end-to-end testing?
- What is test container?
- How do you mock dependencies?
- What is chaos testing?
- What is performance testing?
- What is reliability testing?
- How would you migrate a monolith to microservices?
- How do you debug production issues in distributed systems?
- How do you handle cross-service transactions?
- How do you prevent cascading failures?
- How would you design a globally distributed system?
- How do you achieve exactly-once processing?
- How do you design idempotent APIs?
- How do you handle versioning in APIs?
- How would you design a payment system?
- How would you design a high-scale notification system?
- How would you design a real-time fraud detection platform?
- How would you design microservices for banking systems?
- How do you optimize Kafka for massive throughput?
- How do you handle schema evolution in event-driven systems?
- What are the biggest anti-patterns in microservices?
- How do you handle distributed tracing at scale?
- How do you ensure consistency across services?
- How do you design multi-tenant microservices?
- How do you reduce operational complexity?
- What are the biggest lessons learned from production microservices?