SOA-C02 Practice Exam 58 — 20 Questions

Question 1

A SysOps administrator is reviewing AWS Cost Explorer and notices that data transfer costs from EC2 to the internet are high. The EC2 instances are in a VPC with a NAT Gateway in a public subnet. The route table for private subnets sends 0.0.0.0/0 traffic to the NAT Gateway. The application serves content to users over the internet. Which change will LEAST impact application performance while reducing costs?

Accepted Answer

Purchase a Dedicated NAT Gateway in the same region to get lower data processing rates.. The correct answer is C. Purchasing a Dedicated NAT Gateway in the same region does not reduce costs; the NAT Gateway itself incurs costs. Option A is wrong because reducing NAT Gateway size limits throughput and may impact performance. Option B is wrong because an egress-only Internet Gateway is for IPv6 only. Option D is wrong because using a VPC Gateway Endpoint for S3 reduces costs for S3 traffic but not general internet traffic.

Answer

Replace the NAT Gateway with a smaller NAT Gateway to reduce hourly charges.

Answer

Use an egress-only Internet Gateway for the private subnets.

Answer

Implement a VPC Gateway Endpoint for Amazon S3 to keep S3 traffic within AWS.

Question 2

A SysOps administrator reviews the Lambda invocation metrics for a function. The function processes data from an S3 bucket and is triggered by S3 events. The cost for this function is higher than expected. What should the administrator do to reduce costs?

Accepted Answer

Increase the function's memory allocation to reduce execution time.. The correct answer is B. The function has very high invocations during peak hours (12:00-14:00). Increasing memory reduces execution time, which can lower total cost because Lambda pricing is based on compute time. Option A is wrong because reducing memory increases duration and may increase cost. Option C is wrong because the function is already triggered by events; changing to scheduled invocation may not meet requirements. Option D is wrong because concurrency limit does not reduce total invocations.

Answer

Set a reserved concurrency limit to cap the number of concurrent executions.

Answer

Change the function to be invoked on a schedule instead of by S3 events.

Answer

Reduce the function's memory allocation to lower cost per invocation.

Question 3

A company wants to reduce costs for their Amazon RDS for PostgreSQL database. Which TWO actions would help achieve this?

Accepted Answer

Stop the database instance during non-business hours.. Options B and D are correct because stopping idle DB instances saves compute costs, and using Reserved Instances for predictable workloads reduces hourly costs. Option A is wrong because Multi-AZ increases costs. Option C is wrong because enabling deletion protection does not reduce costs. Option E is wrong because increasing backup retention increases storage costs.

Answer

Enable Multi-AZ deployment for high availability.

Answer

Enable deletion protection to prevent accidental deletion.

Answer

Increase the backup retention period to 35 days.

Question 4

A company has a web application that uses an Application Load Balancer (ALB) and an Auto Scaling group of EC2 instances. The Auto Scaling group uses a dynamic scaling policy based on average CPU utilization. The SysOps administrator notices that during traffic spikes, the scaling policy adds instances too slowly, causing performance degradation. Which action should the administrator take to improve performance without significantly increasing costs?

Accepted Answer

Change the scaling policy to a target tracking policy with a target CPU utilization of 70%.. Option A is correct because a target tracking policy with a higher CPU threshold (e.g., 70%) can be more responsive than a step scaling policy. Option B is wrong because increasing the cooldown period would slow scaling down further. Option C is wrong because using a simple scaling policy with a higher threshold may not be as responsive. Option D is wrong because a scheduled scaling policy is not suitable for unpredictable spikes.

Answer

Use a scheduled scaling policy to add instances during known peak hours.

Answer

Increase the cooldown period for the scaling policy to allow instances to warm up.

Answer

Switch to a simple scaling policy that scales out when CPU exceeds 80%.

Question 5

A SysOps administrator notices that the monthly bill for Amazon S3 has increased significantly. The company uses S3 for storing application logs and user uploads. The logs are accessed rarely but must be retained for 3 years. User uploads are accessed frequently for the first 30 days, then rarely after. Which S3 lifecycle policy will optimize storage costs?

Accepted Answer

Transition logs to S3 Glacier Deep Archive after 30 days, and transition user uploads to S3 Standard-IA after 30 days, then to Glacier Deep Archive after 90 days.. The correct answer is D. This policy transitions objects to cost-effective storage classes based on access patterns. Option A is wrong because logs should be moved to Glacier Deep Archive for long-term retention. Option B is wrong because logs are rarely accessed but need retention, so moving to S3 Standard-IA is insufficient cost savings. Option C is wrong because user uploads should not be immediately archived; they are accessed frequently initially.

Answer

Transition user uploads to S3 Glacier Deep Archive after 30 days, and transition logs to S3 Glacier after 90 days.

Answer

Move logs to S3 Glacier Deep Archive after 30 days, and delete user uploads after 1 year.

Answer

Transition logs to S3 Standard-IA after 30 days, and transition user uploads to S3 One Zone-IA after 30 days.

Question 6

A company has a production RDS MySQL instance with 500 GB of gp2 storage. The database experiences high read traffic. The SysOps team needs to improve read performance at minimal cost. What should they do?

Accepted Answer

Create one or more RDS Read Replicas in the same region and direct read traffic to them.. Option A is correct because adding Read Replicas offloads read queries from the primary instance, improving performance cost-effectively. Option B is wrong because migrating to Aurora is more expensive. Option C is wrong because gp3 might not provide enough IOPS for read-heavy workloads. Option D is wrong because vertical scaling is more costly than horizontal scaling.

Answer

Migrate the database to Amazon Aurora with Auto Scaling enabled.

Answer

Change the storage type to gp3 and increase IOPS.

Answer

Upgrade the DB instance to a larger instance type with more vCPUs.

Question 7

A company runs a web application on EC2 instances with an Auto Scaling group. The application uses an Amazon RDS MySQL database. During a traffic spike, the database CPU utilization reaches 90%. The SysOps team needs to improve database performance cost-effectively. Which THREE actions should they take?

Accepted Answer

Enable RDS Performance Insights to identify slow queries.. Options A, B, and D are correct because adding Read Replicas offloads read traffic, enabling RDS Performance Insights helps identify bottlenecks, and using RDS Proxy reduces connection overhead. Option C is wrong because vertical scaling (upgrading instance) is more expensive than horizontal scaling. Option E is wrong because Multi-AZ does not improve performance; it's for failover.

Answer

Enable Multi-AZ for the RDS instance.

Answer

Upgrade the RDS instance to a larger instance type.

Question 8

A company runs a batch processing job every night that takes 2 hours on a single m5.xlarge EC2 instance. The job is fault-tolerant and can be interrupted. The SysOps administrator wants to reduce costs. Which solution is MOST cost-effective?

Accepted Answer

Use a Spot Instance with a Spot Fleet that includes a fallback to On-Demand if Spot is not available.. Option D is correct because using Spot Instances with a fleet and fallback to On-Demand provides cost savings while ensuring the job completes. Option A is wrong because Reserved Instances require a commitment and may not be cost-effective for a 2-hour daily job. Option B is wrong because Dedicated Hosts are expensive. Option C is wrong because using only On-Demand is more expensive than using Spot.

Answer

Use an On-Demand instance and set up a CloudWatch alarm to stop it when the job completes.

Answer

Use a Dedicated Host to run the job.

Answer

Purchase a Reserved Instance for the m5.xlarge instance.

Question 9

A company uses Amazon CloudWatch Logs to store application logs from EC2 instances. The log volume is 100 GB per day, and logs are retained for 1 year. The SysOps administrator wants to reduce costs while maintaining compliance. Which solution is MOST effective?

Accepted Answer

Export logs to Amazon S3 and configure a lifecycle policy to transition them to Glacier Deep Archive after 30 days.. The correct answer is B. Exporting logs to S3 and using S3 lifecycle policies to transition to cheaper storage classes (e.g., Glacier Deep Archive) is cost-effective for long-term retention. Option A is wrong because CloudWatch Logs Insights is a query tool, not a cost reduction method. Option C is wrong because reducing retention period violates compliance. Option D is wrong because disabling encryption does not reduce costs significantly and may violate security policies.

Answer

Reduce the log retention period to 30 days.

Answer

Disable server-side encryption for the log group to reduce overhead.

Answer

Use CloudWatch Logs Insights to query logs instead of storing them.

Question 10

A company uses AWS Lambda functions to process messages from an SQS queue. The Lambda function is configured with a reserved concurrency of 100. The SQS queue receives unpredictable spikes of up to 10,000 messages per second. The function takes about 1 second to process a message. The SysOps team notices that during spikes, messages are being throttled and appear in the DLQ. How can the team resolve this while optimizing cost?

Accepted Answer

Increase reserved concurrency to 1000 and enable batch processing with a batch size of 10 in the SQS event source mapping.. Option D is correct because increasing reserved concurrency allows Lambda to scale to handle the spike, and using batch processing reduces the number of invocations, lowering cost. Option A is wrong because reducing concurrency would worsen throttling. Option B is wrong because a larger instance type might not be available and increases cost per invocation. Option C is wrong because Lambda cannot be run on EC2 in a serverless manner.

Answer

Reduce the reserved concurrency to 10 to force the function to process messages more slowly.

Answer

Provision an EC2 fleet to poll the SQS queue and invoke the Lambda function.

Answer

Increase the Lambda function memory and timeout to use a larger instance type.

Question 11

A company has three EC2 instances as shown in the exhibit. The company pays for a t3.micro Reserved Instance. Which instance(s) will receive the RI discount?

Accepted Answer

Only i-0abcd1234. Option A is correct because RI discounts apply to running instances of the same instance size (or size flexible family). The t3.micro RI covers t3.micro instances; the t3.medium is larger and not covered. The stopped instance does not run, so no discount. Option B is wrong because the stopped instance does not run. Option C is wrong because t3.medium is not covered. Option D is wrong because only the t3.micro running instance qualifies.

Answer

i-0abcd1234 and i-0abcd5678

Answer

i-0abcd1234 and i-0abcd9012

Answer

All three instances

Question 12

A company has an S3 bucket that stores millions of small objects (1-10 KB) and uses S3 Standard storage. The bucket receives frequent PUT requests and occasional GET requests. The monthly bill shows high costs for S3 PUT requests. Which action would reduce costs?

Accepted Answer

Aggregate small objects into larger files (e.g., 1 MB) before uploading to S3.. Option C is correct because aggregating small objects into larger files reduces the number of PUT requests, which are billed per request. Option A is wrong because S3 Intelligent-Tiering is for storage cost, not request cost. Option B is wrong because S3 Glacier is for archival, and PUT requests to Glacier cost more. Option D is wrong because lifecycle policies do not reduce PUT request costs.

Answer

Move the objects to S3 Glacier Deep Archive to reduce storage cost.

Answer

Move the objects to S3 Intelligent-Tiering to optimize storage costs.

Answer

Use S3 Lifecycle policies to transition objects to S3 Standard-IA after 30 days.

Question 13

A company has a web application running on EC2 instances behind an Application Load Balancer. The application experiences latency spikes during peak hours. Amazon CloudWatch metrics show that CPU and memory are not fully utilized. The SysOps administrator suspects the bottleneck is the database. The database is an RDS for MySQL instance. Which action should the administrator take to improve performance without over-provisioning?

Accepted Answer

Enable RDS Performance Insights to analyze database load and identify slow queries.. The correct answer is B. RDS Performance Insights helps identify database bottlenecks (e.g., slow queries, locks). Option A is wrong because increasing instance size may not address the root cause. Option C is wrong because Multi-AZ improves availability but not performance. Option D is wrong because Read Replicas help with read traffic but not if the bottleneck is writes or locking.

Answer

Add a Read Replica to offload read queries.

Answer

Convert the RDS instance to a Multi-AZ deployment.

Answer

Increase the RDS instance size to the next tier.

Question 14

A company uses CloudFront to distribute content globally. They want to reduce data transfer costs and improve performance for users. What feature should they enable?

Accepted Answer

Enable Origin Shield to create a central caching layer.. Option B is correct because Origin Shield increases cache hit ratio by centralizing requests, reducing origin load and data transfer cost. Option A is wrong because Lambda@Edge adds processing but does not directly reduce transfer. Option C is wrong because it increases cache hits but does not reduce origin requests as effectively as Origin Shield. Option D is wrong because origin failover is for availability, not cost.

Answer

Configure multiple origins with failover.

Answer

Enable Lambda@Edge to modify requests and responses.

Answer

Increase the TTL for cache behaviors to the maximum allowed value.

Question 15

A company has an S3 bucket policy as shown. A developer tries to upload an object using the AWS CLI without the --no-verify-ssl flag. What will happen?

Accepted Answer

The upload will succeed because the CLI uses HTTPS by default.. Option A is correct because the policy denies requests that are not using secure transport (HTTPS). Since the CLI uses HTTPS by default, the request is allowed. Option B is wrong because the default is HTTPS. Option C is wrong because the policy denies HTTP, not HTTPS. Option D is wrong because the policy allows HTTPS requests.

Answer

The upload will succeed only if the developer uses HTTP.

Answer

The upload will fail because the policy denies all s3:* actions.

Answer

The upload will fail because the policy requires explicit HTTPS.

Question 16

A SysOps administrator wants to monitor the cost and usage of AWS resources for different departments. Which AWS service should they use to tag resources and generate cost allocation reports?

Accepted Answer

AWS Cost Explorer with cost allocation tags. Option B is correct because AWS Cost Explorer with cost allocation tags allows filtering by tags. Option A is wrong because AWS Budgets sets alerts, not reporting. Option C is wrong because AWS Trusted Advisor provides optimization recommendations. Option D is wrong because AWS Config tracks configuration, not cost.

Answer

AWS Trusted Advisor

Answer

AWS Budgets

Answer

AWS Config

Question 17

A SysOps administrator is optimizing an AWS Lambda function that processes data from an S3 bucket. The function currently runs with 128 MB memory and a 5-second timeout. The function experiences timeouts for large files. The administrator wants to improve performance and reduce cost. Which TWO actions should they take?

Accepted Answer

Enable provisioned concurrency to reduce cold starts.. Options A and D are correct because increasing memory often reduces execution time and cost due to faster processing, and enabling reserved concurrency prevents cold starts and ensures capacity. Option B is wrong because increasing timeout alone does not improve performance and may increase cost. Option C is wrong because provisioning more functions does not affect a single function's performance. Option E is wrong because moving to S3 Standard-IA is for storage cost, not compute.

Answer

Increase the function timeout to 15 minutes.

Answer

Configure the S3 event notification to use S3 Standard-IA for the input files.

Answer

Create multiple Lambda functions to process different files concurrently.

Question 18

A SysOps administrator is reviewing the monthly AWS bill and notices a significant cost for data transfer from EC2 to the internet. The EC2 instances are in a VPC and serve content to users. Which action would MOST effectively reduce data transfer costs?

Accepted Answer

Use Amazon CloudFront as a content delivery network (CDN).. Option C is correct because CloudFront caches content at edge locations, reducing data transfer from EC2 to the internet. Option A is wrong because using a NAT Gateway adds cost. Option B is wrong because VPC endpoints are for private connectivity to AWS services, not for reducing internet data transfer. Option D is wrong because moving to a different region does not reduce data transfer costs.

Answer

Use VPC endpoints to connect to S3 and DynamoDB.

Answer

Move the EC2 instances to a different AWS Region with lower data transfer rates.

Answer

Use a NAT Gateway to route traffic through a single IP.

Question 19

A company is running a production web application on EC2 instances behind an Application Load Balancer. The company wants to optimize costs without sacrificing performance. Which TWO actions should the SysOps administrator take?

Accepted Answer

Purchase Reserved Instances for the baseline capacity.. Option A (Reserved Instances) provides a significant discount for steady-state workloads, and Option C (Auto Scaling) ensures capacity matches demand, preventing over-provisioning. Option B (Dedicated Hosts) is more expensive and unnecessary. Option D (T3 unlimited) could cause unexpected costs if credits exhausted. Option E (Multiple instance types per AZ) is not a cost optimization.

Answer

Use Dedicated Hosts for all instances to control placement.

Answer

Enable T2/T3 unlimited to handle spikes without throttling.

Answer

Use multiple instance types in each Availability Zone.

Question 20

A SysOps administrator reviews the CloudWatch metrics for an EC2 instance as shown. The instance is part of an Auto Scaling group with a target tracking scaling policy based on average CPU utilization set to 50%. During the time period shown, what is the expected behavior?

Accepted Answer

The Auto Scaling group will scale out because CPU utilization exceeded 50% for several consecutive data points.. Option C is correct because CPU utilization peaks at 95.1% at 00:20, exceeding the 50% target, so the Auto Scaling group should scale out. Option A is wrong because it does exceed the target. Option B is wrong because the average over the hour is around 47%, but the policy reacts to sustained breaches; the peak would trigger scaling. Option D is wrong because scaling would occur.

Answer

The Auto Scaling group will not scale because the average CPU utilization over the hour is below 50%.

Answer

The Auto Scaling group will scale in because the CPU utilization dropped below 50% at the end.

Answer

The Auto Scaling group will not scale because the metric shows a decline after the peak.