SOA-C02 Reliability and Business Continuity Practice Test 2 — 15 Questions

Question 1

A company runs a stateful web application on a single Amazon EC2 instance. The application stores session state in memory and writes critical data to an Amazon EBS volume. The SysOps administrator needs to implement a highly available architecture that can tolerate an Availability Zone (AZ) failure. The administrator plans to use an Auto Scaling group and an Application Load Balancer (ALB). Which combination of steps is required to make the application highly available while preserving session and data durability across AZ failures?

Accepted Answer

Use an Auto Scaling group across multiple AZs, migrate session storage to Amazon ElastiCache (multi-AZ), and migrate application data from EBS to Amazon EFS (file system mounted across AZs).. Option C is correct because it addresses both session state and data durability across AZ failures. Migrating session storage to ElastiCache (multi-AZ) ensures session data survives instance failure, and migrating application data from EBS to EFS provides a shared, multi-AZ file system that persists independently of any single EC2 instance. This combination allows the Auto Scaling group to launch new instances in any AZ and immediately access both session and application data.

Answer

Create an AMI of the current instance, configure an Auto Scaling group with a launch template that uses the AMI, and attach the existing EBS volume to new instances.

Answer

Create a multi-AZ Auto Scaling group and use sticky sessions (session affinity) on the ALB to tie users to specific instances.

Answer

Use an Auto Scaling group in a single AZ and use a Multi-AZ RDS instance for data storage.

Question 2

A company runs a global e-commerce application that uses Amazon DynamoDB as its primary database. The application requires single-digit millisecond read and write latency from any region and must continue to operate during a regional outage with minimal data loss. Which DynamoDB feature should the SysOps administrator enable to meet these requirements?

Accepted Answer

DynamoDB global tables. DynamoDB global tables provide multi-Region, multi-active replication, enabling single-digit millisecond reads and writes from any Region while offering automatic failover and recovery during a regional outage. This feature uses DynamoDB Streams to replicate data across Regions with eventual consistency, meeting the requirement for continued operation with minimal data loss.

Answer

DynamoDB Accelerator (DAX)

Answer

DynamoDB Point-in-Time Recovery (PITR)

Answer

DynamoDB Auto Scaling

Question 3

A company runs a web application on two EC2 instances in different Availability Zones, each with an Elastic IP address. The SysOps administrator needs to automatically route traffic to the healthy instance and fail over if one instance becomes unhealthy. The application must be accessible via a single DNS name. Which Route 53 routing policy should be used?

Accepted Answer

Failover routing policy. The failover routing policy in Amazon Route 53 is designed to route traffic from a primary resource to a secondary resource when the primary becomes unhealthy. In this scenario, the two EC2 instances in different Availability Zones act as primary and secondary endpoints, and Route 53 uses health checks to monitor the primary instance. If the health check fails, Route 53 automatically fails over to the secondary instance, ensuring the application remains accessible via a single DNS name.

Answer

Weighted routing policy

Answer

Geolocation routing policy

Answer

Simple routing policy

Question 4

A company runs an Amazon RDS for MySQL DB instance in us-east-1. The SysOps administrator needs to implement a disaster recovery solution that can recover from a regional outage with a Recovery Point Objective (RPO) of less than 1 second and a Recovery Time Objective (RTO) of less than 1 minute. Which solution should the administrator use?

Accepted Answer

Aurora Global Database. Aurora Global Database is the correct choice because it provides a fully managed cross-region replication solution with a typical RPO of less than 1 second and an RTO of less than 1 minute during a regional failover. It uses a primary cluster in one region and up to five secondary clusters in other regions, with asynchronous replication that is optimized for low latency, meeting the stringent RPO/RTO requirements.

Answer

Multi-AZ deployment

Answer

Cross-region read replica

Answer

Automated snapshot copy to another region

Question 5

A company has an Amazon RDS for PostgreSQL DB instance with Multi-AZ deployment in us-east-1. The SysOps administrator must design a disaster recovery strategy to recover from a regional outage. The Recovery Time Objective (RTO) is 1 hour and the Recovery Point Objective (RPO) is 5 minutes. Which solution meets these requirements at the lowest cost?

Accepted Answer

Create a Read Replica in a different region and promote it during a disaster.. A cross-region Read Replica meets the RPO of 5 minutes because replication is continuous (asynchronous) with minimal lag, and the RTO of 1 hour is achievable by promoting the replica during a disaster. This is the lowest-cost option because it uses a single standby instance in another region without the overhead of a full Multi-AZ deployment or frequent snapshot transfers.

Answer

Take daily snapshots and copy them to another region.

Answer

Use cross-region automated backups.

Answer

Deploy a second Multi-AZ DB instance in another region.

Question 6

A company runs a critical application on Amazon EC2 instances. The application uses an NFS file system stored on an Amazon EFS file system. The SysOps administrator must ensure that the file system is highly available and can withstand an Availability Zone failure. The file system must be accessible from all Availability Zones in the region. Which configuration is required to meet these requirements?

Accepted Answer

Configure the EFS file system for Standard storage class and mount it using the regional DNS name.. Option B is correct because the EFS Standard storage class replicates data across multiple Availability Zones (AZs) within a region, providing high availability and resilience against an AZ failure. Mounting the file system using the regional DNS name ensures that clients in any AZ can reach the file system via the nearest mount target, as the regional DNS name resolves to the mount target IP addresses in the local AZ. This configuration meets the requirement for the file system to be accessible from all AZs in the region while withstanding an AZ outage.

Answer

Configure the EFS file system for One Zone storage class and mount it using the file system ID.

Answer

Configure EFS to use provisioned throughput and mount it using a mount target IP address.

Answer

Enable EFS lifecycle management to move files to Infrequent Access storage class.

Question 7

A company runs a critical database on an Amazon RDS for MySQL DB instance. The SysOps administrator needs to ensure that the database can survive a single Availability Zone failure with minimal downtime. Which configuration should the administrator implement?

Accepted Answer

Enable Multi-AZ deployment.. Multi-AZ deployment for Amazon RDS automatically provisions and maintains a synchronous standby replica in a different Availability Zone. If the primary AZ fails, Amazon RDS automatically fails over to the standby, typically within 60–120 seconds, minimizing downtime without manual intervention. This meets the requirement for surviving a single AZ failure with minimal downtime.

Answer

Enable automatic backups.

Answer

Deploy a read replica in a different AZ.

Answer

Take a manual snapshot and copy it to another AZ.

Question 8

A company runs a critical MySQL database on an Amazon RDS DB instance in a single Availability Zone. The SysOps administrator needs to implement a disaster recovery solution with a Recovery Point Objective (RPO) of 5 minutes and a Recovery Time Objective (RTO) of 1 hour, while minimizing costs. Which solution meets these requirements?

Accepted Answer

Enable cross-Region automated backups to another Region. Option C is correct because cross-Region automated backups replicate transaction logs to another AWS Region with a typical lag of a few minutes, enabling point-in-time recovery (PITR) that can meet an RPO of 5 minutes. When a disaster occurs, you can restore the automated backup to a new DB instance in the destination Region, and the RTO depends on the restore time, which can be under 1 hour for a properly sized instance. This solution minimizes costs by avoiding the continuous compute and storage overhead of a standby replica or read replica.

Answer

Enable Multi-AZ deployment with a synchronous standby replica in another Availability Zone

Answer

Create a cross-Region read replica and promote it to a standalone DB instance during a disaster

Answer

Take daily automated snapshots and copy them to another Region manually

Question 9

A company stores critical data in an Amazon S3 bucket in the us-west-2 Region. The SysOps administrator needs to ensure that all objects are automatically replicated to another AWS Region for disaster recovery. The Recovery Point Objective (RPO) must be less than 15 minutes, and existing objects must also be replicated. Which S3 feature should the administrator use?

Accepted Answer

S3 Cross-Region Replication (CRR) with Replication Time Control (RTC). S3 Cross-Region Replication (CRR) with Replication Time Control (RTC) is the correct choice because it provides automatic, asynchronous replication of objects to a different AWS Region, meeting the RPO of less than 15 minutes by guaranteeing replication within 15 minutes for most objects (99.99% of objects are replicated within 15 minutes). Additionally, CRR can replicate existing objects when configured with the appropriate replication rule and batch operations, satisfying the requirement to replicate all objects.

Answer

S3 Same-Region Replication (SRR)

Answer

S3 Event Notifications with an AWS Lambda function to copy objects to another region

Answer

S3 Transfer Acceleration

Question 10

A company processes orders using an Amazon SQS standard queue. The order processing application occasionally fails to process a message. The SysOps administrator wants to ensure that any message that fails to be successfully processed after three attempts is automatically moved to a separate queue for manual review. Which SQS feature should be configured?

Accepted Answer

Configure a Dead Letter Queue (DLQ) with a redrive policy. A Dead Letter Queue (DLQ) with a configured redrive policy is the correct SQS feature to automatically move messages that have failed processing after a specified number of attempts (in this case, three) to a separate queue for manual review. The redrive policy defines the source queue, the DLQ, and the maximum receive count (maxReceiveCount) threshold. When a message is received from the source queue more times than the maxReceiveCount, SQS automatically redirects it to the DLQ, isolating problematic messages without manual intervention.

Answer

Increase the visibility timeout of the queue

Answer

Convert the queue to a FIFO queue

Answer

Enable redrive allow policy on the queue

Question 11

A company runs a critical application on Amazon EC2 instances across multiple Availability Zones. The application stores state data on a shared Amazon EFS file system. The SysOps administrator needs to ensure that the file system remains available if an entire Availability Zone fails. The file system must also provide low-latency access from all instances. Which configuration meets these requirements?

Accepted Answer

Create an EFS file system with the Standard storage class in the same Region, and mount it from all instances using the regional mount target.. Option C is correct because the EFS Standard storage class stores data redundantly across multiple Availability Zones (AZs) within a Region, ensuring high availability and durability even if an entire AZ fails. By mounting the file system using the regional mount target (which resolves to the EFS file system's regional DNS name), instances in any AZ can access the file system with low latency, as EFS automatically routes traffic to the most appropriate mount target in the same AZ. This configuration meets both the availability and low-latency requirements without additional replication or failover complexity.

Answer

Create an EFS file system with the One Zone storage class and mount it from all instances.

Answer

Create an EFS file system with the Standard storage class, enable replication to another Region, and use DNS failover.

Answer

Create an EFS file system with the Standard storage class, and enable Multi-AZ deployment.

Question 12

A company has an Amazon DynamoDB table with on-demand capacity mode. The SysOps administrator needs to ensure that the table can survive a regional outage. The table is currently in us-east-1. Which feature should be configured to achieve regional resilience with minimal data loss?

Accepted Answer

DynamoDB global tables. DynamoDB global tables provide multi-Region, fully replicated tables that automatically propagate writes to all configured Regions, enabling the table to survive a regional outage with minimal data loss. This feature uses DynamoDB Streams to replicate data asynchronously across Regions, offering recovery point objectives (RPO) of typically under one second. For the requirement of regional resilience, global tables are the correct choice because they maintain active copies in multiple AWS Regions.

Answer

DynamoDB Accelerator (DAX)

Answer

DynamoDB point-in-time recovery

Answer

DynamoDB auto scaling

Question 13

A company runs a critical application on Amazon ECS with the Fargate launch type. The application must remain available if a single Availability Zone fails. The SysOps administrator needs to configure the ECS service for high availability. Which configuration should be used?

Accepted Answer

Use a spread placement strategy across multiple Availability Zones.. Option B is correct because using a spread placement strategy across multiple Availability Zones ensures that ECS tasks are distributed across distinct zones, so the application remains available if a single zone fails. With Fargate, the spread strategy can be applied at the Availability Zone level, and ECS automatically manages task placement to maintain the desired distribution. This configuration meets the high availability requirement by eliminating a single point of failure at the zone level.

Answer

Place tasks in a single Availability Zone.

Answer

Use a binpack placement strategy.

Answer

Increase the desired task count to 10.

Question 14

A company hosts a critical web application on Amazon EC2 instances in a single AWS Region (us-east-1). The SysOps administrator needs to implement a Disaster Recovery (DR) solution using a different AWS Region (us-west-2). The DR plan requires a Recovery Time Objective (RTO) of 1 hour and a Recovery Point Objective (RPO) of 15 minutes. The application uses an Amazon Aurora MySQL DB cluster and static assets stored in an Amazon S3 bucket. Which combination of actions should the administrator take to meet these requirements?

Accepted Answer

Create an Aurora cross-Region read replica in us-west-2. Configure S3 Cross-Region Replication from the source bucket to a destination bucket in us-west-2. During DR, promote the read replica to a primary cluster and update DNS.. Option A is correct because Aurora cross-Region read replicas provide asynchronous replication with an RPO typically under 1 second, easily meeting the 15-minute RPO requirement. Promoting the read replica to a primary cluster in us-west-2 can be completed within minutes, satisfying the 1-hour RTO. S3 Cross-Region Replication (CRR) automatically replicates static assets to the destination bucket in us-west-2 with near-real-time latency, ensuring the S3 data is also current within the RPO window.

Answer

Take a manual snapshot of the Aurora DB cluster every 15 minutes and copy it to us-west-2. Use S3 batch operations to copy assets to us-west-2 daily.

Answer

Enable Aurora Multi-AZ in us-east-1 and configure S3 transfer acceleration to us-west-2.

Answer

Use AWS Database Migration Service (DMS) for continuous replication to a DB instance in us-west-2. Use S3 versioning to keep previous object versions.

Question 15

A company runs a critical application on a single Amazon EC2 instance. The SysOps administrator needs to ensure that if the instance fails, a new instance is automatically provisioned in a different Availability Zone. Which configuration should the administrator implement?

Accepted Answer

Create an Auto Scaling group with the instance in multiple Availability Zones. Option A is correct because an Auto Scaling group (ASG) can be configured with a minimum, desired, and maximum size of 1, spanning multiple Availability Zones (AZs). When the EC2 instance fails, the ASG health check replacement mechanism automatically terminates the unhealthy instance and launches a new one in a different AZ, ensuring the application remains available across AZ boundaries without manual intervention.

Answer

Create a placement group and launch the instance in it

Answer

Place the instance behind an Elastic Load Balancer

Answer

Configure an Amazon Route 53 health check with failover routing