SOA-C02 Reliability and Business Continuity Practice Test 9 — 15 Questions

Question 1

A company has an Auto Scaling group that launches EC2 instances in private subnets. The instances need to download software patches from the internet. Which component must be added to the VPC to allow outbound internet traffic while keeping the instances private?

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

Accepted Answer

A NAT gateway in a public subnet. A NAT gateway in a public subnet allows EC2 instances in private subnets to initiate outbound traffic to the internet (e.g., to download patches) while preventing unsolicited inbound connections. The NAT gateway translates the private IPs to its own Elastic IP and routes traffic through an internet gateway attached to the VPC, keeping instances private.

Answer

An internet gateway attached to the VPC

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A VPC peering connection to a VPC with internet access

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An egress-only internet gateway

Question 2

A team of developers is deploying a new microservice that uses Amazon DynamoDB as its data store. The SysOps administrator must ensure that the application can handle a sudden spike in read traffic without throttling. Which DynamoDB feature can be used to automatically handle increases in read capacity?

Accepted Answer

DynamoDB Auto Scaling. DynamoDB Auto Scaling is the correct feature because it automatically adjusts the provisioned read and write capacity based on actual traffic patterns, preventing throttling during sudden spikes. The SysOps administrator can define a target utilization percentage (e.g., 70%), and DynamoDB Auto Scaling uses the Application Auto Scaling service to increase capacity before requests are throttled, ensuring consistent performance without manual intervention.

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DynamoDB Global Tables

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DynamoDB Time to Live (TTL)

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DynamoDB Accelerator (DAX)

Question 3

A company runs a critical application on Amazon EC2 instances in an Auto Scaling group. The application stores data on an Amazon EBS volume. The SysOps administrator needs to implement a backup strategy that ensures data can be recovered in the event of an AZ failure. Which TWO actions should be taken? (Choose TWO.)

Accepted Answer

Configure automated snapshots using Amazon Data Lifecycle Manager.. Amazon Data Lifecycle Manager (DLM) automates the creation, retention, and deletion of EBS snapshots, providing a scheduled backup mechanism that protects against data loss. Option C is correct because copying snapshots to another region ensures data is recoverable even if an entire AWS Availability Zone (AZ) fails, as the snapshots are stored independently in a different geographic region.

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Increase the EBS volume size to maximize I/O performance.

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Enable EBS encryption using AWS KMS.

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Enable EBS Multi-Attach to allow the volume to be attached to instances in another AZ.

Question 4

A SysOps administrator is designing a highly available architecture for a web application using an Application Load Balancer and an Auto Scaling group across three Availability Zones. The application must be able to withstand the loss of an entire AZ. Which THREE components are necessary to meet this requirement? (Choose THREE.)

Accepted Answer

Launch EC2 instances in at least two Availability Zones.. Launching EC2 instances in at least two Availability Zones (AZs) ensures that if one AZ fails, the Auto Scaling group can still serve traffic from instances in the remaining AZs. This is a fundamental requirement for high availability, as an Auto Scaling group spanning multiple AZs can automatically replace failed instances in other zones. Without multi-AZ deployment, a single AZ failure would cause complete application downtime.

Answer

Use a single NAT gateway to provide internet access.

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Use a cluster placement group for EC2 instances.

Question 5

A company uses Amazon S3 to store backup data. The SysOps administrator needs to ensure that the data is encrypted at rest and that access is limited to only authorized users. Which TWO actions should be taken? (Choose TWO.)

Accepted Answer

Enable default encryption on the S3 bucket using SSE-S3 or AWS KMS.. Enabling default encryption on the S3 bucket using SSE-S3 or AWS KMS ensures that all objects stored in the bucket are encrypted at rest automatically, meeting the encryption-at-rest requirement. This can be configured via the bucket properties, and it applies to any object uploaded without explicit encryption headers.

Answer

Block all public access to the S3 bucket.

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Enable S3 Versioning on the bucket.

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Enable S3 Transfer Acceleration.

Question 6

A company is designing a highly available web application using an Application Load Balancer (ALB) with EC2 instances in an Auto Scaling group across two Availability Zones. Which configuration ensures that the application remains available if one Availability Zone fails?

Accepted Answer

Configure the Auto Scaling group to launch instances in at least two Availability Zones. Configuring the Auto Scaling group to launch instances in at least two Availability Zones ensures that if one AZ fails, the remaining AZ continues to serve traffic. The ALB distributes incoming requests across healthy targets in all enabled AZs, and Auto Scaling replaces failed instances in the remaining AZs automatically, maintaining application availability.

Answer

Use a single large EC2 instance instead of multiple instances

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Disable health checks on the ALB to avoid false positives

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Launch all EC2 instances in a single Availability Zone

Question 7

A SysOps administrator is designing a disaster recovery plan for a critical RDS MySQL database. The database must be available with a Recovery Point Objective (RPO) of less than 1 hour and a Recovery Time Objective (RTO) of less than 2 hours. The primary region is us-east-1. Which solution meets these requirements?

Accepted Answer

Create a cross-Region read replica in us-west-2 and promote it during a disaster. A cross-Region read replica in us-west-2 can be promoted to a standalone primary database in under 2 hours, and the replication lag is typically less than 1 hour, meeting both RPO and RTO requirements. This solution provides continuous asynchronous replication from the primary region, ensuring minimal data loss and fast failover without needing to restore from backups.

Answer

Enable Multi-AZ deployment in the primary region

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Enable automated backups and restore to a new region when needed

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Take daily manual snapshots and copy them to another region

Question 8

A company runs a stateful application on EC2 instances behind a Network Load Balancer (NLB). The application uses sticky sessions (session affinity) to maintain client state. During a deployment, the SysOps administrator needs to replace instances without disrupting active sessions. Which approach should be used?

Accepted Answer

Deregister the old instances from the target group with connection draining enabled, then register new instances. Deregistering instances from the target group with connection draining enabled allows existing connections to complete gracefully before the instances are removed. The Network Load Balancer (NLB) continues to route new connections to the remaining healthy instances, and once draining finishes, new instances can be registered without disrupting active sessions. This approach maintains session affinity (sticky sessions) by ensuring that in-flight requests are completed before the instance is taken out of service.

Answer

Stop the NLB, replace instances, and restart the NLB

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Update the target group health check to remove old instances faster

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Terminate the old instances immediately and launch new ones

Question 9

An organization needs to back up an Amazon EFS file system daily and retain backups for 30 days. Which AWS service provides a managed backup solution for EFS?

Accepted Answer

AWS Backup. AWS Backup is the correct answer because it is a fully managed, policy-based backup service that supports Amazon EFS natively. It allows you to define backup plans with daily schedules and retention rules (e.g., 30 days) without needing to manage any backup infrastructure or scripts. AWS Backup handles the lifecycle of backups, including incremental backups and automatic deletion of expired recovery points.

Answer

Amazon Data Lifecycle Manager (DLM)

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EFS replication to another region

Answer

S3 Lifecycle policies

Question 10

A company is running a critical application on EC2 instances in an Auto Scaling group. The application experiences occasional CPU spikes. The SysOps administrator needs to configure a scaling policy that reacts quickly to increased load but avoids unnecessary scaling actions due to short bursts. Which scaling policy type should be used?

Accepted Answer

Target tracking scaling policy with a CPU utilization target of 70%. Target tracking scaling policy with a CPU utilization target of 70% is correct because it dynamically adjusts the Auto Scaling group's desired capacity to maintain a specified metric (CPU utilization) at the target value. It uses a built-in algorithm that reacts quickly to sustained load increases while smoothing out short bursts by applying a cooldown and proportional control logic, preventing unnecessary scaling actions from transient spikes.

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Manual scaling

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Scheduled scaling policy

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Simple scaling policy

Question 11

A company uses Amazon Route 53 for DNS. They want to ensure that if the primary web server fails, traffic is automatically routed to a secondary server in another region. Which routing policy should be used?

Accepted Answer

Failover routing policy. The Failover routing policy in Amazon Route 53 is specifically designed for active-passive failover configurations. When the primary endpoint fails a health check, Route 53 automatically returns the secondary record in DNS responses, ensuring traffic is routed to the secondary server in another region. This directly meets the requirement for automatic failover between primary and secondary web servers.

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Simple routing policy

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Latency routing policy

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Weighted routing policy

Question 12

A SysOps administrator notices that an RDS instance's storage is nearly full. The instance uses General Purpose SSD (gp2) storage. The administrator needs to increase storage with minimal downtime. Which action should be taken?

Accepted Answer

Modify the RDS instance to increase the allocated storage size. Modifying the RDS instance to increase the allocated storage size is the correct action because RDS for MySQL, MariaDB, PostgreSQL, Oracle, and SQL Server supports dynamic storage scaling with minimal downtime. When you modify the allocated storage for a gp2 volume, RDS performs the modification in the background, and the instance remains available during the process, though you may experience a brief performance impact. This directly addresses the near-full storage condition without requiring a full outage.

Answer

Enable storage auto-scaling

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Delete old data to free up space

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Convert the storage type to Provisioned IOPS

Question 13

A company runs a microservices architecture on Amazon ECS with Fargate. They need to ensure that if a task fails, it is automatically restarted. Which configuration is required?

Accepted Answer

Create an ECS service with a desired count and task definition. An ECS service with a desired count and task definition ensures that Fargate tasks are automatically restarted if they fail. The ECS service scheduler monitors the desired count and replaces any stopped or failed tasks to maintain the specified number of running instances, providing built-in resilience without additional infrastructure.

Answer

Configure a CloudWatch alarm to restart the task

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Define tasks using the ECS RunTask API

Answer

Use an Auto Scaling group for the Fargate tasks

Question 14

A company is designing a backup strategy for its on-premises file servers to AWS. Which TWO services can be used to back up data to AWS? (Choose TWO.)

Accepted Answer

AWS Backup. AWS Backup is correct because it provides a fully managed, policy-based backup service that can centrally automate and manage backups for on-premises file servers via the AWS Backup Gateway (formerly Storage Gateway Virtual Tape Library). It integrates with AWS Storage Gateway to back up on-premises data to S3 and Glacier, supporting file-level recovery without needing custom scripts.

Answer

AWS Snowball

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Amazon EFS

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S3 Transfer Acceleration

Question 15

A SysOps administrator is designing a highly available architecture for a web application using an Application Load Balancer (ALB) with EC2 instances in an Auto Scaling group. Which TWO configurations are required to ensure high availability? (Choose TWO.)

Accepted Answer

Configure the ALB with health checks for the target group. Health checks allow the ALB to monitor the status of each EC2 instance in the target group. If an instance fails health checks, the ALB automatically stops routing traffic to it, preventing user requests from reaching a failed instance. This is essential for maintaining application availability and is a core feature of the ALB's high-availability design.

Answer

Launch all EC2 instances in a single Availability Zone to reduce latency

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Use t2.micro instances to reduce cost

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Disable health checks to reduce load on the ALB