Unit 5: Cloud-Native Development - Practice Quiz

1 What is the main goal of cloud-native architecture?

2 Which technology commonly packages a cloud-native application with its dependencies?

3 What does it mean for microservices to be loosely coupled?

4 How do loosely coupled services commonly communicate?

5 What is the purpose of service discovery in a microservices system?

6 Where are service locations commonly recorded for service discovery?

7 What does a load balancer do?

8 Why does a load balancer perform health checks?

9 What is autoscaling?

10 Which metric is commonly used to trigger autoscaling?

11 Which data management pattern is common in microservices?

12 What does eventual consistency mean in a distributed system?

13 According to the twelve-factor app methodology, where should deployment-specific configuration be stored?

14 What does the twelve-factor methodology recommend for application dependencies?

15 How should twelve-factor application processes generally operate?

16 Who manages the underlying servers in a serverless architecture?

17 What commonly causes a serverless function to execute?

18 Why does Netflix use microservices in its streaming platform?

19 What organizational benefit is associated with Amazon's use of small, service-focused teams?

20 Why did Uber adopt microservices as its platform grew?

21 An online retailer wants each product team to deploy its service independently without coordinating every release. Which architectural decision best supports this goal?

22 A payment service publishes a PaymentCompleted event without knowing which services will consume it. What is the main architectural benefit?

23 Service instances receive dynamic IP addresses and may be replaced frequently. How should an API gateway locate healthy instances?

24 Four service instances have active connection counts of 12, 7, 19, and 4. Which instance would a least-connections load balancer select for the next request?

25 A worker service processes messages from a queue. CPU usage stays low even when thousands of messages are waiting. Which scaling metric is most appropriate?

26 An order workflow updates the order, payment, and inventory services, each with its own database. Which approach best handles a failure after payment succeeds but inventory reservation fails?

27 A service uses different database URLs in development, testing, and production. According to the twelve-factor methodology, where should these values be stored?

28 A containerized service writes logs to local files, but those logs disappear whenever the container is replaced. Which change best follows twelve-factor guidance?

29 A serverless function may receive the same payment event more than once because the platform retries failed deliveries. Which design most effectively prevents duplicate charges?

30 Users experience high latency on the first request after a serverless function has been idle. Which measure most directly reduces this cold-start impact?

31 A video platform wants playback recommendations to remain available even when the personalization service is failing. Which pattern associated with Netflix-style resilience best addresses this requirement?

32 A large e-commerce company wants teams to own services from development through production. Which practice most closely matches Amazon's service-oriented operating model?

33 A ride-sharing platform must continuously match drivers with nearby riders as locations change. Which architecture is most suitable for this Uber-like workload?

34 A product catalog service becomes unavailable, but the storefront should continue showing recently viewed products. Which cloud-native design principle best supports this behavior?

35 A customer service must add a field to its response without immediately breaking existing consumers. Which API change best preserves loose coupling?

36 A terminated service instance remains listed in the registry and continues receiving requests. Which mechanism would most directly reduce this problem?

37 A web application stores user sessions only in each server's local memory. Users lose their sessions when requests reach different instances. What is the most scalable correction?

38 A service repeatedly scales out and then scales in within a few minutes because its CPU utilization fluctuates near the target threshold. Which configuration change best limits this oscillation?

39 A reporting dashboard needs fast queries across data produced by several microservices, but direct cross-service joins are causing failures and high latency. Which design is most appropriate?

40 A service requires several minutes to shut down because it keeps temporary work only in process memory. Which redesign best supports the twelve-factor principle of disposability?

41 A request passes synchronously through services A, B, and C. Each service independently retries a failed downstream call up to two additional times. If C remains unavailable, what architectural change most directly prevents retry amplification while preserving transient-failure recovery?

42 A producer publishes CustomerAddressChanged events. Several consumers fail whenever the producer adds optional fields or changes its internal database schema. Which redesign best reduces structural coupling?

43 Instances register with a discovery service using leases. During a network partition, an isolated instance continues serving traffic but cannot renew its lease. Which behavior best limits routing to stale instances after connectivity is restored?

44 A service has instances with similar CPU capacity, but request durations vary from 10 ms to 30 s. Connections are reused through HTTP/2, so connection count poorly represents active work. Which load-balancing policy is most appropriate?

45 Jobs arrive at an average rate of jobs per minute. One worker processes jobs per minute, and the target utilization is . Ignoring burst headroom, how many workers are required to sustain the average rate?

46 An order workflow reserves inventory, authorizes payment, and schedules shipment across independently owned databases. Atomic distributed transactions are unavailable. Which design best handles a payment failure after inventory has been reserved?

47 The same container image must run in development, staging, and production, but each environment uses different credentials and service endpoints. Which implementation most closely follows twelve-factor methodology?

48 A serverless function processes messages from an at-least-once queue and charges a customer through an external payment API. A timeout may occur after the API accepts a charge but before the function records success. Which mechanism best prevents duplicate charges?

49 A streaming platform modeled after Netflix must continue presenting useful content when its personalized recommendation service is unavailable. Which resilience strategy best matches this requirement?

50 An Amazon-style retail platform partitions checkout into regional cells. A malformed configuration causes failures in one cell. Which property most directly reduces the incident's blast radius?

51 An Uber-like dispatch system stores driver locations that update every few seconds. Matching must remain low-latency, while temporary location staleness is acceptable. Which architecture is most suitable?

52 A user request triggers asynchronous work across six services and three message brokers. Logs contain timestamps but cannot reliably reconstruct one request because clocks differ and messages are retried. Which observability change provides the strongest causal trace?

53 Service A publishes an event and then waits synchronously for acknowledgments from every current consumer before committing its own transaction. What form of coupling has primarily been reintroduced?

54 A client-side discovery cache has a 60-second TTL. After an instance is terminated, clients continue routing to it until cache expiration, causing failures. Which modification reduces stale routing without making the registry a dependency for every request?

55 A cache cluster is scaled from 100 to 101 nodes. The system must minimize key remapping while keeping load reasonably balanced. Which technique best satisfies both goals?

56 A CPU-based autoscaler repeatedly adds instances during short traffic spikes, then removes them before their caches warm. Latency worsens despite adequate average capacity. Which tuning is most likely to stabilize the system?

57 A service updates its database and publishes an integration event. Crashes between these operations sometimes produce missing events or events for rolled-back writes. Which pattern best resolves the dual-write problem without requiring a distributed transaction?

58 A web service scales horizontally, but user sessions are stored in each process's memory. Requests routed to a different instance lose session state. Which change most directly applies the twelve-factor processes principle?

59 A latency-sensitive serverless API receives unpredictable bursts but has a strict 100 ms response objective. Profiling shows that cold initialization alone takes 600 ms. Which intervention most directly addresses the measured tail-latency cause?

60 A read model consumes ordered account events from a partitioned stream. Events for the same account must remain ordered, but events for different accounts may be processed concurrently. Which partitioning strategy satisfies this constraint?