SAA-C03 Design Resilient Architectures Practice Test 21 — 15 Questions

Question 1

A media company stores original video masters in an Amazon S3 bucket in the us-east-1 Region. Compliance requires that a readable copy of every object exists in eu-west-1 within 15 minutes of upload, and that objects deleted in the source bucket do not automatically disappear from the destination. Which S3 feature should the solutions architect enable?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

S3 Cross-Region Replication with S3 Replication Time Control and DeleteMarkerReplication disabled. S3 Cross-Region Replication is the AWS feature that asynchronously copies new and updated objects to a bucket in another Region. S3 Replication Time Control adds an SLA that 99.99% of objects replicate within 15 minutes, matching the compliance window. Disabling DeleteMarkerReplication keeps the destination copy intact when the source object is deleted, which is exactly the retention behaviour the compliance team requires.

Answer

S3 Same-Region Replication into a bucket in us-east-1 with S3 Object Lock in compliance mode

Answer

AWS Backup with a cross-Region backup vault and a daily scheduled backup plan for the bucket

Answer

S3 Transfer Acceleration on the source bucket with a lifecycle rule transitioning objects to S3 Glacier Deep Archive

Question 2

A logistics company runs an order-tracking service on Amazon EC2 instances that write state to an Amazon DynamoDB table. A recent incident showed that a single Availability Zone failure caused the service to lose capacity, and the team also discovered that a developer accidentally deleted a production table. The architect must improve both Availability Zone resilience and protection against accidental table deletion. (Choose two.)

Accepted Answer

Enable DynamoDB point-in-time recovery on the table and attach a resource-based policy that denies the dynamodb:DeleteTable action to non-administrative principals.. Zone resilience for the compute tier comes from running instances across multiple Availability Zones behind a load balancer, so a single zone loss does not remove all capacity. Accidental table deletion is mitigated by enabling point-in-time recovery, which allows restore to a recent point in time, and by restricting who holds the delete-table permission so the mistake is far less likely to recur.

Answer

Create a DynamoDB global secondary index on the partition key used by the tracking queries and project all attributes into the index.

Answer

Enable DynamoDB Streams on the table and write a consumer that copies every change into an Amazon S3 bucket for long-term retention.

Answer

Convert the DynamoDB table to use provisioned capacity mode with auto scaling so that read and write capacity automatically adjusts during traffic spikes.

Question 3

A financial analytics platform runs an Amazon Aurora MySQL cluster with one writer and two readers. During month-end reporting, read traffic spikes and the application sometimes receives TooManyConnections errors on the reader endpoint. The architect wants to absorb bursts without changing application code and must keep failover behaviour intact. Which change meets these requirements?

Accepted Answer

Add an Amazon RDS Proxy in front of the Aurora cluster and point the application at the proxy endpoint. Amazon RDS Proxy sits between the application and Aurora, maintaining a warm pool of database connections that are shared across many client connections. This absorbs connection bursts and prevents TooManyConnections errors without application changes beyond updating the endpoint. Because RDS Proxy is failover-aware, it automatically routes to the new writer during a failover, preserving the resilience behaviour the architect requires.

Answer

Increase the aurora_max_connections parameter on the cluster parameter group and reboot the readers

Answer

Replace the reader endpoint with a Network Load Balancer that distributes TCP connections across the Aurora readers

Answer

Convert the readers to Aurora Replicas in a second Region and use a global database secondary cluster

Question 4

A financial services firm runs a batch settlement job on a fleet of Amazon EC2 instances that pull work from an Amazon SQS queue. The job must not lose messages if an instance is terminated mid-processing, and duplicate processing must be minimized because each settlement charge is expensive. The team also wants to avoid indefinite reprocessing of a message that repeatedly fails. Which two changes should the solutions architect make to meet these requirements? (Choose two.)

Accepted Answer

Increase the queue's visibility timeout so it exceeds the maximum expected processing time.. Raising the visibility timeout above the maximum processing time prevents a still-running message from being redelivered to another consumer, which directly reduces duplicate settlement charges. Attaching a dead-letter queue with a maximumReceiveCount moves repeatedly failing messages aside after a set number of receives, so they are not reprocessed indefinitely while healthy traffic continues.

Answer

Switch the queue to an Amazon SQS FIFO queue with content-based deduplication.

Answer

Store a processing flag in an Amazon ElastiCache for Redis cluster and check it before charging.

Answer

Enable long polling on the queue by setting ReceiveMessageWaitTimeSeconds to 20.

Question 5

A healthcare company runs a stateless patient-intake API on a fleet of Amazon EC2 instances in a single VPC. The compliance team requires the workload to survive the complete loss of one Availability Zone with no manual intervention, and the instances must be replaced automatically if they fail health checks. The application stores no local state and writes all data to Amazon RDS. Which approach meets these requirements with the LEAST operational effort?

Accepted Answer

Create an Auto Scaling group spanning two Availability Zones with a launch template, and attach it to an Application Load Balancer target group with health checks enabled.. Resilience to a full Availability Zone loss requires capacity spread across at least two zones, and automatic instance replacement requires an Auto Scaling group whose health checks are tied to the load balancer. Combining a multi-AZ Auto Scaling group with an Application Load Balancer target group delivers both properties without manual intervention, which is exactly what the compliance requirement demands.

Answer

Launch the instances directly with a launch template into two subnets in different Availability Zones, and attach each instance to a Network Load Balancer with cross-zone load balancing enabled.

Answer

Place the instances behind an Application Load Balancer in one Availability Zone and configure an Amazon Route 53 health check with a failover record pointing to a static Elastic IP address.

Answer

Deploy the instances as an Auto Scaling group in a single Availability Zone and enable detailed CloudWatch monitoring with a scaling policy based on CPU utilization.

Question 6

A healthcare provider runs a patient-record API on Amazon EC2 instances behind an Application Load Balancer in one AWS Region. The API reads from an Amazon RDS for MySQL DB instance. The provider must be able to continue serving read traffic if the primary database instance fails, and must minimize the time the application is unavailable. Which change should a solutions architect make?

Accepted Answer

Convert the DB instance to an Amazon RDS Multi-AZ DB instance deployment so a standby is maintained in another Availability Zone.. Database high availability with minimal application downtime is achieved by running Amazon RDS Multi-AZ, which keeps a synchronously replicated standby in another Availability Zone and performs automatic failover to it. Because the failover updates the same endpoint, applications reconnect without manual reconfiguration.

Answer

Store the database credentials in AWS Secrets Manager and rotate them automatically on a schedule.

Answer

Create a read replica in the same Availability Zone and point read traffic to it using a custom application load-balancing layer.

Answer

Enable automated backups with a longer retention period and increase the DB instance class size.

Question 7

A SaaS provider runs a multi-tenant application on Amazon EC2 instances behind an Application Load Balancer. Tenants are identified by a subdomain, and each tenant's data is stored in a separate Amazon S3 bucket. The provider wants HTTPS with a single certificate, automatic renewal, and the ability to add new tenant subdomains without redeploying or replacing the certificate. Which solution meets these requirements?

Accepted Answer

Request a public certificate in AWS Certificate Manager for the apex domain and a wildcard for its subdomains, validate it with DNS, and attach it to the Application Load Balancer HTTPS listener.. A public ACM certificate that includes the apex domain and a wildcard for its subdomains covers every current and future tenant hostname. DNS validation lets ACM renew the certificate automatically while the validation records persist, and attaching the certificate to the Application Load Balancer listener provides HTTPS termination without touching the application when new tenants are onboarded.

Answer

Import a self-signed certificate covering all current tenant subdomains into AWS Certificate Manager and attach it to the Application Load Balancer listener.

Answer

Terminate TLS on the EC2 instances using certificates issued by AWS Private Certificate Authority, and pass traffic from the Application Load Balancer to the instances over HTTP.

Answer

Store the private key and certificate in AWS Secrets Manager, and configure the Application Load Balancer to retrieve and rotate the certificate at each renewal.

Question 8

A media company runs a transcoding fleet on Amazon EC2 instances behind an Application Load Balancer in a single Availability Zone. The business requires the workload to survive the loss of that Availability Zone with no manual intervention and minimal downtime. The instances store intermediate files on instance store volumes and the fleet is managed by an Auto Scaling group. Which change should a solutions architect make to meet the requirement?

Accepted Answer

Add a second Availability Zone to the Auto Scaling group and configure the Application Load Balancer with subnets in both Availability Zones.. Resilience to an Availability Zone failure requires spreading compute across multiple zones and giving the load balancer subnets in each of those zones. The Auto Scaling group then replaces failed instances in the surviving zone while the load balancer routes only to healthy targets, delivering continuous service without human action.

Answer

Increase the desired capacity of the Auto Scaling group so that more instances run in the existing Availability Zone.

Answer

Convert the instances to Spot Instances and configure a placement group to keep them close together.

Answer

Enable detailed CloudWatch monitoring and create an alarm that notifies operators when an instance becomes unhealthy.

Question 9

A logistics company runs a stateless order-tracking API on Amazon EC2 instances in an Auto Scaling group behind an Application Load Balancer. The architect must ensure the API survives the loss of an entire Availability Zone and that unhealthy instances are replaced automatically. (Choose two.)

Accepted Answer

Attach an Application Load Balancer target group health check and enable ELB health checks on the Auto Scaling group so unhealthy instances are terminated and replaced. Zone-level resilience with EC2 Auto Scaling requires the group to span multiple Availability Zones with enough desired capacity to run in each, so a single zone failure leaves serving capacity. Automatic replacement of unhealthy instances requires ELB health checks on the group, which makes the group act on the load balancer's health determination rather than only EC2 status checks. Together these two settings deliver the required survival and self-healing behaviour.

Answer

Enable termination protection on all EC2 instances so the Auto Scaling group cannot remove them during a zone failure

Answer

Create a second Auto Scaling group in a different Region and use Amazon Route 53 latency-based routing to distribute traffic

Answer

Place the instances in a single Availability Zone and enable detailed CloudWatch monitoring with a 1-minute granularity

Question 10

A logistics firm runs an order-processing service that reads from an Amazon SQS queue and writes results to an Amazon DynamoDB table. During a marketing event, the consumer fleet scaled out aggressively and DynamoDB began returning ProvisionedThroughputExceededException errors, causing messages to be retried and some orders to be processed twice. The architects want to absorb traffic spikes without overprovisioning capacity and without duplicate processing. Which combination of changes should they make?

Accepted Answer

Switch the DynamoDB table to on-demand capacity mode and have the consumer use a conditional write with an idempotency key derived from the message ID.. The symptom set has two distinct causes: a capacity model that cannot absorb spikes and a consumer that is not idempotent. On-demand capacity mode lets the table follow the workload without manual provisioning, while a conditional write on a stable idempotency key makes repeated delivery harmless. Addressing both together is what stops the throttling and the duplicate orders.

Answer

Add a global secondary index on the message ID and query it before each write to check whether the order has already been stored.

Answer

Increase the table's provisioned write capacity units substantially and enable DynamoDB Streams so that duplicate items can be detected after the fact.

Answer

Move the table to a different AWS Region and enable DynamoDB Accelerator (DAX) in front of it to cache the writes during the spike.

Question 11

A media company runs a stateless transcoding fleet on Amazon EC2 instances spread across three Availability Zones behind a Network Load Balancer. The fleet must keep processing jobs even if an entire Availability Zone becomes unavailable, and the architect wants to minimize manual intervention. Which combination of actions should the architect take to meet these requirements?

Accepted Answer

Create an Auto Scaling group that spans the three Availability Zones, enable ELB health checks, and configure the group to replace unhealthy instances automatically.. The requirement is automatic recovery from the loss of a whole Availability Zone. An Auto Scaling group distributed across three zones, combined with ELB health checks, continuously replaces unhealthy instances and rebalances capacity into surviving zones. That removes the need for manual intervention. The other configurations either concentrate risk in one zone, rely on interruptible capacity, or alter load balancing behavior without providing replacement capacity.

Answer

Launch the instances as a Spot Fleet with a capacity-optimized allocation strategy and attach an Application Load Balancer in front of the fleet.

Answer

Configure the Network Load Balancer with cross-zone load balancing disabled and register all instances in a single target group.

Answer

Place all instances in a single Availability Zone and create an Amazon Route 53 latency routing policy pointing at the Network Load Balancer.

Question 12

A startup runs a customer-facing web application on a single Amazon EC2 instance in one Availability Zone, with the database on the same instance. The founders want the application to survive the failure of that Availability Zone with minimal changes and no server management for the database tier. Which action should the solutions architect take first?

Accepted Answer

Move the database to Amazon RDS with a Multi-AZ DB instance deployment and place the application instances in an Auto Scaling group spanning multiple Availability Zones.. The core problem is that both the application and database reside in a single Availability Zone. Relocating the database to Amazon RDS with Multi-AZ deployment gives automatic failover and removes database server management, while running the application in a multi-AZ Auto Scaling group provides compute redundancy. Together these changes let the application survive a zonal failure with minimal rework.

Answer

Create an Amazon Machine Image of the instance and copy it to a second Region for disaster recovery.

Answer

Enable termination protection on the EC2 instance and take regular Amazon EBS snapshots.

Answer

Place an Application Load Balancer in front of the single instance and enable sticky sessions.

Question 13

A media startup stores user-uploaded video files in an Amazon S3 bucket in the us-east-1 Region. The compliance team requires that the data remain recoverable if an entire AWS Region becomes unavailable, and that recovery can be performed by pointing applications at a different endpoint. Cost should be minimized while still meeting the requirement. Which solution should a solutions architect recommend?

Accepted Answer

Enable S3 Cross-Region Replication to a bucket in a second Region and configure the application to use the replica bucket endpoint during a regional failure.. Protecting S3 data against a full regional outage requires a copy in a different Region, which Cross-Region Replication provides asynchronously and cost-effectively. Versioning, lifecycle transitions, and Transfer Acceleration all operate within the source Region and therefore cannot deliver recovery when that Region is lost.

Answer

Configure an S3 Lifecycle rule to transition objects to S3 Glacier Deep Archive after 30 days for regional durability.

Answer

Enable S3 Transfer Acceleration on the bucket so uploads and downloads are faster during a regional event.

Answer

Enable S3 Versioning on the existing bucket and rely on version history to restore objects if the Region fails.

Question 14

A financial analytics platform ingests events into an Amazon Kinesis Data Stream with four shards. During month-end peaks, producers receive ProvisionedThroughputExceededException errors and consumers fall behind. The architects want to increase capacity without changing producer code and must preserve the order of records that share the same partition key. What should they do?

Accepted Answer

Increase the number of open shards using UpdateShardCount to a higher count.. Producer throttling on a Kinesis data stream is resolved by adding shards, since each shard provides a fixed write and read capacity. UpdateShardCount performs this online, and because the partition key still hashes to one shard, per-key ordering is maintained and no producer changes are required.

Answer

Enable server-side encryption on the stream and increase the retention period to 365 days.

Answer

Switch the consumers to enhanced fan-out and raise the number of registered consumers.

Answer

Replace the Kinesis Data Stream with an Amazon SQS FIFO queue and have consumers poll it.

Question 15

A startup runs a nightly batch job on a single Amazon EC2 instance that stores results in an Amazon EBS volume. The job takes six hours, and the team wants to resume from the last completed step if the instance is terminated unexpectedly. Which approach provides the required durability with the least operational effort?

Accepted Answer

Store intermediate results in Amazon S3 and write a checkpoint file after each completed step. Storing intermediate results in Amazon S3 with checkpoint files gives durable, externally persisted state that survives instance termination and lets the job resume from the last completed step. S3 is managed, so there is no replication or volume management to operate, which matches the low-effort requirement. Snapshots and RAID do not provide automatic step-level resume without custom logic.

Answer

Enable EBS Multi-Attach on the volume and attach it to a standby instance in another Availability Zone

Answer

Move the EBS volume to a RAID 1 configuration across two Availability Zones using mdadm

Answer

Create a snapshot schedule for the EBS volume and restore from the latest snapshot after termination