Free Alibaba Cloud CAP-C01 Practice Exam with Questions & Answers | Set: 2

Option A offers the strongest combination of resilience, predictable baseline capacity, flexibility, and reduced cost. Nine standard pay-as-you-go ECS instances are spread evenly across three zones and can support the scheduled workloads that have strict SLA requirements. The remaining three instances use lower-cost preemptible/spot capacity for user jobs that can tolerate interruption or delay.

Alibaba Cloud describes spot instances as offering the same compute performance as ordinary pay-as-you-go ECS but at substantially lower prices, with the trade-off that capacity can be reclaimed. This makes spot capacity appropriate for interruption-tolerant workloads but inappropriate as the sole capacity supporting strict SLAs.

A Savings Plan discounts eligible pay-as-you-go ECS usage while preserving significantly greater flexibility than traditional reserved-instance matching. Current Alibaba Cloud documentation states that Savings Plans apply discounts to pay-as-you-go usage and can offer flexibility across instance configurations; they do involve a one- or three-year hourly spend commitment, but they do not provision or reserve fixed ECS capacity.

Options C and D concentrate too much reliable capacity into fewer zones or place excessive workload on interruptible capacity. Option A therefore provides the best workload-tiering and multi-zone design among the available choices.

Study Guide reference: Building Highly Available, Performant Cloud Architecture — multi-zone ECS, workload resilience, Savings Plans, and spot instances.

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Express Connect combined with Cloud Enterprise Network Transit Routers provides the appropriate enterprise hybrid-network architecture. Express Connect establishes a dedicated private circuit from the on-premises data center to Alibaba Cloud, providing lower latency, predictable performance, high bandwidth, and reduced exposure compared with Internet-based VPN connectivity.

The Express Connect circuit terminates through a Virtual Border Router. That VBR can be attached to CEN, where Transit Routers provide hub-and-spoke connectivity to multiple VPCs instead of requiring separate point-to-point connections for every VPC. Transit Routers can connect VPCs, VBRs, VPN attachments, and inter-region Transit Routers, enabling centralized routing across a geographically distributed enterprise network.

Alibaba Cloud also supports connecting an on-premises VBR and multiple VPCs to a Transit Router so that all attached networks communicate over private connectivity. Cross-region CEN connections then extend the architecture to VPCs in additional regions.

VPN Gateway relies on Internet-based encrypted tunnels and would require more tunnel management at scale. NAT Gateway performs address translation and does not provide private hybrid interconnection. Apsara Stack is an on-premises cloud platform rather than the required connectivity service.

Study Guide reference: Building Enterprise-grade Networks on Alibaba Cloud — Express Connect, CEN, Transit Router, hybrid networking, and cross-region connectivity.

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The core problem is durability during transient processing or network failures. A topic provides publish/subscribe notification delivery, but placing an SMQ queue behind the topic creates a persistent buffer between the notification producer and the Function Compute consumer. Alibaba Cloud supports subscribing a queue to an SMQ topic so that every message published to the topic is copied into the queue and retained for consumption.

Function Compute should then process records from the queue. Queue semantics provide the required failure recovery: after a consumer receives a message, it becomes temporarily invisible. The consumer deletes the message only after successful processing. If processing fails—for example because of a temporary connectivity problem—the message is not deleted and becomes visible again after the visibility timeout, allowing another processing attempt.

Function Compute also supports SMQ queue triggers with configurable retries, fault-tolerance behavior, and dead-letter handling, which can further strengthen this architecture.

Increasing memory does not fix network reliability, and multi-region deployment alone does not guarantee message persistence. A durable queue therefore prevents transient failures from silently losing ingestion work.

Study Guide reference: Core Infrastructure Deep Dive — Simple Message Queue, Function Compute, durable asynchronous processing, retries, and decoupled event-driven architecture.

Alibaba Cloud CDN addresses the front-end performance problem by caching static resources at edge Points of Presence close to users. Instead of every image, JavaScript file, stylesheet, or other cacheable object being retrieved from the origin application, CDN returns cached copies from nearby edge nodes. This reduces network latency and decreases load on the original application servers. Alibaba Cloud specifically identifies reduced latency and lower origin workload as primary benefits of CDN.

Read/write splitting addresses database-side pressure. ApsaraDB RDS for MySQL can use database proxy functionality to direct write operations to the primary instance and distribute eligible read operations to read-only instances. This is especially effective for read-heavy web applications because it reduces CPU and I/O load on the primary database and increases aggregate read throughput.

A multi-zone database improves availability rather than directly solving page-load latency. AnalyticDB is an analytical database and should not replace RDS simply to handle transactional data. OSS is optimized for static objects; hosting dynamic application content there does not fit its object-storage model.

Study Guide reference: Building Highly Available, Performant Cloud Architecture — CDN acceleration, RDS read scaling, database proxies, and application performance optimization.

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Basic security groups support group-based authorization, allowing one security group ' s rules to reference another security group rather than requiring administrators to maintain long lists of individual IP addresses. Alibaba Cloud explicitly recommends source-security-group authorization for internal application communication because it is more manageable than maintaining individual private IP addresses or CIDR ranges.

This distinction is important because advanced security groups do not support another security group as an authorization object. Their primary benefit is higher private-IP capacity for very large deployments, not simplified service-to-service authorization.

For workloads residing in different VPCs, network connectivity must first exist through VPC Peering, Cloud Enterprise Network, PrivateLink, or another appropriate mechanism. Security groups do not themselves establish cross-VPC routes; they enforce authorization once the relevant network path exists.

Centralized logging provides visibility but does not simplify the actual authorization rules. Network ACLs operate at the vSwitch/subnet boundary and are less appropriate for application-tier identity based on security-group membership.

Thus, basic security groups with group-based authorization provide the intended simplified access-control model.

Study Guide reference: Securing Workloads on Alibaba Cloud — security groups, group-based authorization, least privilege, and VPC workload segmentation.

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