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CCNA Cost and Performance Optimization Questions

75 of 199 questions · Page 2/3 · Cost and Performance Optimization · Answers revealed

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76
MCQhard

A company has a stateful web application that requires session persistence. The application is deployed on EC2 instances behind an Application Load Balancer. The company wants to improve performance by caching frequently accessed data. Which solution is MOST cost-effective?

A.Increase the instance size of the EC2 instances to improve performance.
B.Use Amazon ElastiCache with Memcached to cache session data and frequently accessed data.
C.Use Amazon CloudFront to cache static and dynamic content at the edge.
D.Enable sticky sessions (Session Affinity) on the ALB.
AnswerB

ElastiCache improves performance by caching data and is cost-effective.

Why this answer

ElastiCache with Memcached is a cost-effective in-memory caching solution that can improve performance by caching frequently accessed data. It supports session storage. ELB sticky sessions (Session Affinity) ensure requests from the same user go to the same instance, but do not cache data.

Increasing instance size improves performance but at a higher cost. CloudFront caches content at the edge, not application data.

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77
MCQhard

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?

A.Move the objects to S3 Glacier Deep Archive to reduce storage cost.
B.Aggregate small objects into larger files (e.g., 1 MB) before uploading to S3.
C.Move the objects to S3 Intelligent-Tiering to optimize storage costs.
D.Use S3 Lifecycle policies to transition objects to S3 Standard-IA after 30 days.
AnswerB

Fewer PUT requests reduce request costs.

Why this answer

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.

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78
MCQeasy

A company runs a batch processing job on a single EC2 instance that runs for 2 hours every night. The job is fault-tolerant and can be interrupted. The SysOps administrator wants to minimize compute costs. What is the MOST cost-effective solution?

A.Use an On-Demand instance to ensure the job runs every night.
B.Purchase a Reserved Instance for 1 year to get a discount.
C.Launch a Dedicated Host to ensure consistent performance.
D.Use a Spot Instance that can be interrupted but is significantly cheaper.
AnswerD

Spot Instances provide large cost savings for fault-tolerant jobs.

Why this answer

A Spot Instance is the most cost-effective choice because the job is fault-tolerant and can be interrupted, allowing you to leverage unused AWS EC2 capacity at up to 90% discount compared to On-Demand pricing. Since the job runs for only 2 hours nightly and can handle interruptions, Spot Instances provide the lowest compute cost while meeting the workload requirements.

Exam trap

The trap here is that candidates often choose Reserved Instances for any recurring workload, failing to recognize that the short duration (2 hours/night) and interruptibility of the job make Spot Instances far more cost-effective without the long-term commitment.

How to eliminate wrong answers

Option A is wrong because using an On-Demand instance incurs the highest per-hour cost with no discount, which is not cost-effective for a fault-tolerant batch job that can be interrupted. Option B is wrong because purchasing a Reserved Instance for 1 year requires a long-term commitment and upfront payment, which is wasteful for a job that runs only 2 hours per night (approximately 730 hours per year) and does not benefit from the steady-state usage discount. Option C is wrong because a Dedicated Host is a physical server dedicated to your use, which is significantly more expensive and unnecessary for a single batch processing job that does not require dedicated hardware or licensing compliance.

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79
MCQeasy

A SysOps administrator wants to identify underutilized Amazon EC2 instances that could be downsized to reduce costs. The administrator needs a tool that provides recommendations based on historical utilization data. Which AWS service should the administrator use?

A.AWS Trusted Advisor
B.AWS Compute Optimizer
C.AWS Cost Explorer
D.AWS Budgets
AnswerB

Compute Optimizer provides specific recommendations to downsize or terminate underutilized EC2 instances based on usage patterns.

Why this answer

AWS Compute Optimizer is the correct service because it analyzes historical utilization metrics (CPU, memory, network, and storage) for EC2 instances and generates specific downsizing recommendations to reduce cost without sacrificing performance. It uses machine learning to identify underutilized resources and provides actionable guidance, making it the ideal tool for this use case.

Exam trap

The trap here is that candidates often confuse AWS Trusted Advisor's idle instance check with Compute Optimizer's detailed, ML-driven downsizing recommendations, but Trusted Advisor only flags instances with low average CPU utilization (e.g., below 10%) without considering memory, network, or storage patterns.

How to eliminate wrong answers

Option A is wrong because AWS Trusted Advisor provides general best-practice checks (e.g., idle instances, security groups) but does not offer granular, ML-based downsizing recommendations based on historical utilization data. Option C is wrong because AWS Cost Explorer focuses on visualizing and analyzing cost and usage trends, not on providing specific EC2 instance type recommendations for downsizing. Option D is wrong because AWS Budgets allows you to set cost thresholds and alerts, but it does not analyze historical utilization or generate downsizing recommendations.

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80
MCQeasy

A company wants to receive alerts when its AWS costs exceed a certain threshold. Which AWS service should be used?

A.Amazon CloudWatch
B.AWS Cost Explorer
C.AWS Trusted Advisor
D.AWS Budgets
AnswerD

Allows setting cost budgets and sending alerts.

Why this answer

AWS Budgets allows you to set custom cost and usage budgets and receive alerts when actual or forecasted costs exceed a defined threshold. It directly supports cost-based alerting with actions such as sending an SNS notification or applying an IAM policy to restrict resources when the budget limit is breached.

Exam trap

The trap here is that candidates confuse AWS Budgets with AWS Cost Explorer, assuming Cost Explorer can send alerts, when in fact Cost Explorer is only a reporting and analysis tool without native alerting capabilities.

How to eliminate wrong answers

Option A is wrong because Amazon CloudWatch monitors AWS resource utilization and application performance metrics, not cost thresholds; while it can trigger alarms on billing metrics if you enable detailed billing metrics, it is not the primary service for cost-based budget alerts. Option B is wrong because AWS Cost Explorer provides visualization and analysis of historical cost data but does not support proactive threshold-based alerts. Option C is wrong because AWS Trusted Advisor offers cost optimization recommendations and checks for idle resources, but it does not allow you to set custom cost thresholds or send alerts when costs exceed a specific amount.

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81
MCQeasy

A company wants to monitor the performance of its Amazon RDS for MySQL database. The database is experiencing high CPU utilization during peak hours. The SysOps administrator needs to identify the queries causing the load. Which AWS service should be used?

A.Amazon RDS Performance Insights
B.AWS CloudTrail
C.Amazon Inspector
D.Amazon CloudWatch Logs
AnswerA

Performance Insights identifies top queries by load.

Why this answer

Option C is correct because Amazon RDS Performance Insights provides a dashboard that visualizes database load and helps identify the queries that are causing high CPU usage. Option A is wrong because Amazon CloudWatch Logs only collects log files, not query performance data. Option B is wrong because AWS CloudTrail records API activity, not database queries.

Option D is wrong because Amazon Inspector is a vulnerability management service, not a database performance tool.

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82
MCQhard

A SysOps administrator is troubleshooting high CPU utilization on an RDS for MySQL instance. The application is read-heavy. Which optimization technique would improve performance and potentially reduce costs?

A.Delete unused indexes from the database.
B.Implement RDS Read Replicas to offload read traffic.
C.Increase the allocated storage size.
D.Enable Multi-AZ deployment for failover support.
AnswerB

Read Replicas reduce load on the primary instance, improving performance and allowing cost savings.

Why this answer

Option A is correct because adding Read Replicas offloads read queries, reducing CPU on the primary and allowing use of smaller instance types. Option B is wrong because Multi-AZ is for high availability, not performance. Option C is wrong because increasing storage doesn't improve CPU.

Option D is wrong because deleting unused indexes reduces storage but not CPU.

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83
MCQeasy

A company uses Amazon S3 to store log files. The logs are accessed frequently for the first 30 days, then rarely accessed after that. The company must retain logs for 7 years for compliance. What is the MOST cost-effective storage solution?

A.Use S3 Standard for 30 days and then transition to S3 Glacier Deep Archive.
B.Use S3 Standard for 7 years.
C.Use S3 One Zone-IA for 30 days and then transition to S3 Glacier Flexible Retrieval.
D.Use S3 Intelligent-Tiering for the entire 7 years.
AnswerA

This minimizes cost by using low-cost deep archive for long-term retention.

Why this answer

S3 Lifecycle policies can transition objects from S3 Standard to S3 Glacier Deep Archive after 30 days, minimizing costs while meeting compliance. S3 Glacier Flexible Retrieval is more expensive than Deep Archive for long-term archival. S3 Intelligent-Tiering adds monitoring costs.

S3 One Zone-IA is not suitable for long-term archival due to lower durability.

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84
MCQmedium

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?

A.Use an On-Demand instance and set up a CloudWatch alarm to stop it when the job completes.
B.Use a Spot Instance with a Spot Fleet that includes a fallback to On-Demand if Spot is not available.
C.Use a Dedicated Host to run the job.
D.Purchase a Reserved Instance for the m5.xlarge instance.
AnswerB

Spot Instances are cost-effective for fault-tolerant jobs, and the fallback ensures completion.

Why this answer

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.

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85
MCQeasy

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?

A.Use VPC endpoints to connect to S3 and DynamoDB.
B.Use Amazon CloudFront as a content delivery network (CDN).
C.Move the EC2 instances to a different AWS Region with lower data transfer rates.
D.Use a NAT Gateway to route traffic through a single IP.
AnswerB

CloudFront reduces data transfer from EC2 by serving cached content from edge locations.

Why this answer

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.

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86
Multi-Selecteasy

A SysOps administrator needs to reduce costs for an Amazon RDS for PostgreSQL database. The database is used for a reporting application that only runs during business hours (9 AM to 5 PM). Which TWO actions would reduce costs without losing data?

Select 2 answers
A.Take a snapshot before stopping to preserve data.
B.Delete the database during off-hours and restore it each morning.
C.Convert the database to a read replica of another database.
D.Use a Multi-AZ cluster for high availability.
E.Stop the database during off-hours.
AnswersA, E

Ensures data is saved and can be restored.

Why this answer

Stopping the database during off-hours stops billing for instance hours. Creating a snapshot before stopping ensures data is preserved. Option A is wrong because deleting the database loses data.

Option B is wrong because converting to a read replica does not reduce cost. Option D is wrong because using a Multi-AZ cluster increases costs.

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87
MCQmedium

A company uses an Amazon DynamoDB table with provisioned capacity. The average write usage is 500 write capacity units (WCU) but regularly spikes to 2,000 WCU during business hours. The SysOps administrator wants to reduce costs without affecting performance during the spikes. Which solution should the administrator implement?

A.Enable DynamoDB auto scaling
B.Switch to DynamoDB on-demand capacity mode
C.Purchase reserved capacity for 2,000 WCU
D.Use DynamoDB Time to Live (TTL) to delete old items
AnswerA

Auto scaling adjusts provisioned capacity based on actual usage, handling spikes and reducing cost during low usage.

Why this answer

DynamoDB auto scaling allows the table to automatically adjust its provisioned write capacity between a minimum and maximum range based on actual traffic. By setting the minimum WCU to cover the average usage (500) and the maximum to handle the spikes (2,000), the administrator pays only for the baseline capacity most of the time, while the service scales up during spikes without manual intervention or over-provisioning.

Exam trap

The trap here is that candidates often confuse on-demand mode as a cost-saving measure for spiky workloads, but in reality, on-demand is more expensive than provisioned capacity with auto scaling when there is a predictable baseline, and the question specifically asks to reduce costs without affecting performance.

How to eliminate wrong answers

Option B is wrong because switching to on-demand capacity mode would eliminate the need to manage capacity but would result in significantly higher costs for the described workload, as on-demand charges per write request are higher than provisioned capacity, especially when the baseline usage is predictable. Option C is wrong because purchasing reserved capacity for 2,000 WCU would lock the company into paying for that high capacity 24/7, even during off-peak hours when usage is only 500 WCU, leading to wasted expenditure. Option D is wrong because DynamoDB Time to Live (TTL) is a feature for automatically expiring and deleting old items to manage storage costs, not for handling write capacity spikes or optimizing provisioned throughput costs.

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88
Multi-Selectmedium

A SysOps administrator is optimizing costs for an AWS account. The account has multiple EC2 instances running 24/7 with varying utilization. Which TWO actions will help reduce costs without impacting performance? (Choose TWO.)

Select 2 answers
A.Use AWS Compute Optimizer to right-size instances.
B.Use larger instance types to improve performance.
C.Enable detailed CloudWatch monitoring for all instances.
D.Enable termination protection on all instances.
E.Purchase Reserved Instances for instances that run consistently.
AnswersA, E

Compute Optimizer recommends optimal instance sizes based on utilization.

Why this answer

The correct answers are A and D. Converting to reserved instances provides significant discount for steady-state workloads. Right-sizing instances based on CloudWatch metrics ensures you are not over-provisioned.

Option B is wrong because increasing instance size increases costs. Option C is wrong because disabling termination protection does not affect costs. Option E is wrong because detailed monitoring incurs additional charges.

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89
MCQmedium

A SysOps administrator needs to reduce costs for a fleet of EC2 instances that run a stateless web application. The instances are currently On-Demand. The workload runs 24/7 for the next 12 months. Which pricing model provides the greatest cost savings?

A.Use Dedicated Hosts.
B.Use Spot Instances.
C.Purchase Standard Reserved Instances for a 1-year term.
D.Purchase Convertible Reserved Instances for a 1-year term.
AnswerC

Provides up to 40% discount for steady-state usage.

Why this answer

Standard Reserved Instances (RIs) for a 1-year term provide a significant discount (up to 40%) over On-Demand pricing for workloads that run continuously 24/7. Since this stateless web application runs constantly for the next 12 months, Standard RIs offer the greatest cost savings among the options, as they are designed for steady-state usage and do not require flexibility in instance family or operating system.

Exam trap

The trap here is that candidates often choose Spot Instances (Option B) thinking they are always cheaper, but they overlook the requirement for 24/7 availability and the risk of interruption, which makes them unsuitable for a stateless web application that must run continuously without disruption.

How to eliminate wrong answers

Option A is wrong because Dedicated Hosts are a physical server dedicated to your use, which incurs additional costs (per-host billing) and does not provide the same discount level as Reserved Instances; they are used for licensing or compliance requirements, not cost savings for a stateless web app. Option B is wrong because Spot Instances can be interrupted with a 2-minute warning, making them unsuitable for a 24/7 stateless web application that requires constant availability; they are designed for fault-tolerant or batch workloads, not always-on production traffic. Option D is wrong because Convertible Reserved Instances offer flexibility to change instance attributes (family, OS, tenancy) but have a lower discount (typically 10-20% less than Standard RIs) for the same 1-year term, making them less cost-effective for a fixed, predictable workload.

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90
MCQeasy

A company stores large volumes of log data in Amazon S3. The logs are accessed frequently for the first 30 days, then occasionally for the next 60 days, and after 90 days they are rarely accessed but must be retained for 7 years for compliance. The SysOps administrator wants to minimize storage costs while ensuring data is available when needed. Which S3 lifecycle policy configuration should be applied?

A.Transition objects to S3 Standard-IA after 30 days, and to S3 Glacier after 60 days. Delete after 7 years.
B.Transition objects to S3 Glacier Deep Archive after 30 days, and delete after 7 years.
C.Transition objects to S3 One Zone-IA after 30 days, and to S3 Glacier Deep Archive after 90 days. Delete after 7 years.
D.Transition objects to S3 Standard-IA after 30 days, and to S3 Glacier Deep Archive after 90 days. Delete after 7 years.
AnswerD

This lifecycle policy matches the access patterns: frequent access -> Standard-IA after 30 days, occasional access for next 60 days (still in IA), then rarely accessed -> Deep Archive after 90 days. Deep Archive is the lowest-cost storage option for long-term retention. Deleting after 7 years meets compliance. This is the most cost-effective configuration.

Why this answer

Option D is correct because it aligns the lifecycle transitions with the access patterns: frequent access for the first 30 days (S3 Standard), occasional access for the next 60 days (S3 Standard-IA), and rare access after 90 days (S3 Glacier Deep Archive, the lowest-cost storage class for long-term retention). The deletion after 7 years meets compliance requirements while minimizing costs by using progressively cheaper storage classes.

Exam trap

The trap here is that candidates may choose Option A because they think S3 Glacier is the standard archival tier, but they overlook that S3 Glacier Deep Archive is cheaper for 7-year retention and that the occasional-access period (days 31–90) is better served by S3 Standard-IA, not S3 Glacier.

How to eliminate wrong answers

Option A is wrong because transitioning to S3 Glacier after 60 days (instead of 90) would incur unnecessary retrieval costs and slower access during the occasional-access period (days 31–90), and S3 Glacier is more expensive than S3 Glacier Deep Archive for long-term retention. Option B is wrong because moving directly to S3 Glacier Deep Archive after 30 days ignores the frequent-access period, causing high retrieval costs and latency for logs that are still accessed often. Option C is wrong because S3 One Zone-IA is not resilient to AZ failures and is unsuitable for compliance data that must be retained for 7 years; also, transitioning after 30 days to One Zone-IA does not match the occasional-access pattern (days 31–90) as well as Standard-IA.

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91
MCQhard

A company runs a production Amazon DynamoDB table with provisioned capacity of 1000 write capacity units (WCU). The table experiences unpredictable spikes up to 2000 WCU, causing throttling. The SysOps administrator wants to minimize cost while handling the spikes. Which solution should be used?

A.Switch to on-demand capacity mode.
B.Increase provisioned WCU to 2000 to cover the peak.
C.Enable DynamoDB Auto Scaling with minimum 1000, maximum 2000 WCU.
D.Use a DynamoDB Accelerator (DAX) cache.
AnswerA

On-demand mode instantly accommodates usage spikes without capacity planning. While typically more expensive for steady-state workloads, for unpredictable spikes it can be cost-effective because you don't pay for unused capacity. It eliminates throttling.

Why this answer

Switching to on-demand capacity mode eliminates throttling during unpredictable spikes by automatically scaling write capacity up to the required 2000 WCU without any manual intervention or pre-provisioning. This minimizes cost because you pay only for the actual reads and writes consumed, avoiding the fixed cost of over-provisioning for peak capacity that may be rarely used.

Exam trap

The trap here is that candidates often choose DynamoDB Auto Scaling (Option C) thinking it handles spikes instantly, but they overlook the inherent scaling delay and the fact that it still requires a maximum capacity setting that may not cover sudden bursts, leading to throttling.

How to eliminate wrong answers

Option B is wrong because increasing provisioned WCU to 2000 permanently incurs higher base costs even during low-traffic periods, which contradicts the goal of minimizing cost. Option C is wrong because DynamoDB Auto Scaling adjusts capacity based on utilization metrics, but it cannot react instantly to sudden spikes up to 2000 WCU, leading to throttling during the scaling delay. Option D is wrong because DynamoDB Accelerator (DAX) is an in-memory cache that improves read performance, not write capacity, and does not address write throttling caused by insufficient WCU.

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92
MCQhard

A SysOps team manages a fleet of EC2 instances used for batch processing. The workload runs daily, taking approximately 6 hours. The instances are launched via an Auto Scaling group using On-Demand instances from a custom AMI. The team has noticed that while the instances are running, the CPU utilization is moderate, but the memory usage is high. After the batch completes, the instances are terminated. The team wants to reduce costs without changing the architecture. Which solution would be MOST cost-effective?

A.Modify the Auto Scaling group to use a mixed instances policy with a percentage of Spot Instances and a fallback to On-Demand.
B.Use a Compute Savings Plan covering the entire compute usage across the account.
C.Change the instance type to a memory-optimized family to reduce the number of instances needed.
D.Purchase Reserved Instances for the expected daily usage to get a lower hourly rate.
AnswerA

Spot Instances are ideal for fault-tolerant workloads like batch processing, offering large discounts.

Why this answer

Option A is correct because Spot Instances can provide significant discounts (up to 90%) for fault-tolerant batch workloads, and the team can use a mixed instances policy with On-Demand as a fallback. Option B (memory optimized instances) would likely increase cost. Option C (reserved instances) is not suitable for short-lived, sporadic workloads.

Option D (savings plan) could help but still requires committing to a consistent amount, which may not align with the varying batch size. Option A offers the most flexibility and cost savings.

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93
Multi-Selecthard

A company runs a web application on Amazon EC2 instances behind an Application Load Balancer (ALB). The ALB is configured with a target group that has health checks. The application is experiencing intermittent 503 errors. The SysOps administrator needs to identify the root cause. Which THREE steps should the administrator take to diagnose the issue? (Choose THREE.)

Select 3 answers
A.Check the security group rules for the ALB.
B.Monitor the CloudWatch metric 'HealthyHostCount' for the target group.
C.Increase the unhealthy threshold count in the health check settings.
D.Enable and review the ALB access logs.
E.Check the target group health check logs for failed health checks.
AnswersB, D, E

This metric shows the number of healthy targets.

Why this answer

Correct options: A, B, D. Option A is correct because checking the ALB access logs can reveal the HTTP response codes and client IPs. Option B is correct because reviewing the target group health check logs helps determine if instances are failing health checks.

Option D is correct because CloudWatch metrics like HealthyHostCount can show if the number of healthy instances drops. Option C is wrong because increasing the unhealthy threshold will make the ALB less sensitive, but it does not diagnose the cause. Option E is wrong because checking the security group of the ALB is not directly related to 503 errors; 503 errors typically indicate that there are no healthy targets.

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94
Multi-Selecteasy

A company wants to monitor the performance of its application running on EC2. Which TWO metrics should be monitored to detect performance bottlenecks? (Choose TWO.)

Select 2 answers
A.Network Packets In
B.CPU Utilization
C.Status Check Failed
D.Disk Space Utilization
E.Memory Utilization
AnswersB, E

High CPU indicates a bottleneck.

Why this answer

Options A and C are correct. CPU utilization (A) and Memory utilization (C) are key performance metrics. Option B is wrong because Disk space is not a metric by default; it requires custom scripts.

Option D is wrong because Network packets in is not a standard performance metric. Option E is wrong because Status check is for health, not performance.

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95
MCQmedium

A company has an EC2-based application that runs at inconsistent times. The workloads are fault-tolerant and can be interrupted. Which purchasing option provides the most cost savings?

A.Reserved Instances
B.On-Demand Instances
C.Dedicated Hosts
D.Spot Instances
AnswerD

Spot Instances offer significant discounts for fault-tolerant workloads.

Why this answer

Option B is correct because Spot Instances offer the largest discount (up to 90%) for interruptible workloads. Option A is wrong because On-Demand has no discount. Option C is wrong because Reserved Instances require a commitment and are for steady-state workloads.

Option D is wrong because Dedicated Hosts are expensive and unnecessary.

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96
MCQhard

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?

A.Reduce the reserved concurrency to 10 to force the function to process messages more slowly.
B.Increase reserved concurrency to 1000 and enable batch processing with a batch size of 10 in the SQS event source mapping.
C.Provision an EC2 fleet to poll the SQS queue and invoke the Lambda function.
D.Increase the Lambda function memory and timeout to use a larger instance type.
AnswerB

Higher concurrency allows handling spikes, batch processing reduces invocations.

Why this answer

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.

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97
MCQhard

A SysOps administrator is investigating a cost increase in a production AWS account. They notice that an EC2 instance with a Reservation has been running continuously for months. The instance type is m5.large in us-east-1. The administrator sees that the instance is using a Standard Reserved Instance (RI) that was purchased 6 months ago for a 1-year term. However, the current utilization shows that the instance is only used for 4 hours per day. What should the administrator do to optimize costs without affecting availability?

A.Stop the instance during off-hours using Instance Scheduler, but keep the RI as-is.
B.Sell the current RI on the Reserved Instance Marketplace and purchase a new Convertible RI for a smaller instance type.
C.Modify the existing RI to a smaller instance size (e.g., m5.large to m5.xlarge? no, smaller: e.g., t3.medium) and use Auto Scaling with a schedule to start/stop the instance during business hours.
D.Convert the RI to a Convertible RI and exchange it for a larger instance family to get more compute per hour.
AnswerC

Modifying RI to a smaller size matches usage; scheduled stop reduces running hours.

Why this answer

Option B is correct because modifying the RI to a smaller size can better match the usage pattern, and using Auto Scaling with a scheduled scaling puts the instance to sleep when not needed. Option A is wrong because selling on the Reserved Instance Marketplace would lose the upfront payment and not address the over-provisioning. Option C is wrong because converting to On-Demand is more expensive for the hours used.

Option D is wrong because simply stopping the instance during off-hours does not change the RI benefit; the RI will still be applied to the stopped instance (though RI cannot be applied to stopped instances; it would be wasted).

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98
MCQhard

A company is running a critical application on Amazon RDS for MySQL. The database is experiencing high read traffic, causing performance issues. The SysOps administrator needs to improve read performance while keeping costs low. Which solution should the administrator choose?

A.Enable Multi-AZ deployment
B.Increase the DB instance class to a larger size
C.Use Amazon ElastiCache to cache read results
D.Add one or more Read Replicas in the same Region
AnswerD

Offloads reads effectively and is cost-efficient.

Why this answer

Option A is correct because adding Read Replicas offloads read traffic from the primary DB, improving performance at low cost. Multi-AZ is for high availability, not read scaling. Larger instance class increases cost.

ElastiCache can help but may be overkill and adds complexity and cost.

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99
MCQmedium

A SysOps team is using CloudWatch to monitor CPU utilization of EC2 instances. They want to receive a notification when average CPU exceeds 80% for 5 consecutive minutes. Which combination of services should they use?

A.CloudWatch Metrics, CloudWatch Alarm, and AWS Lambda
B.AWS Config, CloudWatch Alarm, and Amazon SNS
C.CloudWatch Metrics, CloudWatch Alarm, and Amazon SNS
D.CloudWatch Logs, CloudWatch Alarm, and AWS Lambda
AnswerC

Standard pattern for metric-based alerts.

Why this answer

Option A is correct because CloudWatch Metrics collect CPU data, CloudWatch Alarm triggers when threshold is breached, and SNS sends notifications. CloudWatch Logs is for log data, not metrics. Lambda is not needed for simple notification.

Systems Manager is for management, not monitoring.

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100
MCQeasy

A SysOps administrator manages a web application running on Amazon EC2 instances that run 24/7 for the next 12 months. The workload is steady and predictable. Which EC2 purchasing option provides the highest cost savings for this use case?

A.Standard Reserved Instances
B.Spot Instances
C.On-Demand Instances
D.Savings Plans (Compute)
AnswerA

Correct. Standard Reserved Instances offer the highest discount for a steady, predictable 24/7 workload with a 1-year or 3-year term.

Why this answer

Standard Reserved Instances provide the highest cost savings for a steady, predictable 24/7 workload over a 12-month period because they offer a significant discount (up to 72% compared to On-Demand) in exchange for a commitment to a specific instance family, region, and term length. Since the workload runs continuously without interruption, the upfront payment or partial upfront payment for a 1-year term maximizes savings without the risk of interruption or the need for flexibility.

Exam trap

The trap here is that candidates often choose Savings Plans (Compute) because they offer flexibility across instance families, but for a predictable, steady-state workload with a fixed instance type, Standard Reserved Instances provide the highest discount and capacity guarantee, making them the optimal choice for cost savings.

How to eliminate wrong answers

Option B is wrong because Spot Instances are designed for fault-tolerant, flexible workloads that can handle interruptions, not for a steady 24/7 production web application that requires reliability. Option C is wrong because On-Demand Instances offer no upfront commitment but have the highest per-hour cost, making them the least cost-effective for a predictable, always-on workload. Option D is wrong because Savings Plans (Compute) provide flexibility across instance families and regions but typically offer slightly lower discounts than Standard Reserved Instances for a specific, steady-state workload with a known instance type and region.

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101
MCQhard

A company uses this IAM policy to restrict S3 uploads to the STANDARD storage class only. A developer tries to upload an object to the bucket using the CLI without specifying a storage class. What will happen?

A.The upload will fail because the condition does not allow PutObject.
B.The upload will succeed if the bucket has a default storage class of STANDARD-IA.
C.The upload will succeed because the default storage class is STANDARD.
D.The upload will fail because the condition requires explicit specification of the storage class.
AnswerC

Default storage class is STANDARD, which matches the condition.

Why this answer

Option A is correct because the condition requires the storage class to be STANDARD. When no storage class is specified, the default is STANDARD, so the upload succeeds. Option B is wrong because the condition is satisfied.

Option C is wrong because the default is STANDARD, not STANDARD-IA. Option D is wrong because the policy allows PutObject.

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102
MCQeasy

A SysOps administrator wants to monitor the cost of EC2 instances. Which AWS service should be used to visualize and track costs over time?

A.AWS CloudWatch
B.AWS Budgets
C.AWS Trusted Advisor
D.AWS Cost Explorer
AnswerD

Cost Explorer provides graphs and cost trends.

Why this answer

Option D is correct because AWS Cost Explorer is designed for cost visualization and analysis. CloudWatch is for performance metrics, Trusted Advisor provides recommendations, and Budgets sets alerts.

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103
MCQmedium

A SysOps administrator manages a fleet of Amazon EC2 instances. The administrator needs to identify underutilized instances and receive recommendations for instance type changes to reduce costs. Which AWS service should be used to provide these rightsizing recommendations?

A.AWS Cost Explorer
B.AWS Trusted Advisor
C.AWS Compute Optimizer
D.Amazon CloudWatch Dashboard
AnswerC

AWS Compute Optimizer uses machine learning to analyze historical utilization and provides actionable recommendations to right-size EC2 instances, Auto Scaling groups, and other resources, helping to reduce costs and improve performance.

Why this answer

AWS Compute Optimizer is the correct service because it uses machine learning to analyze historical utilization metrics (CPU, memory, network, and storage) of EC2 instances and generates rightsizing recommendations, including instance type changes, to reduce costs and improve performance. It directly addresses the need to identify underutilized instances and provide actionable recommendations for cost optimization.

Exam trap

The trap here is that candidates often confuse AWS Compute Optimizer with AWS Trusted Advisor, because both offer cost optimization checks, but Compute Optimizer is the only service that provides detailed, ML-driven rightsizing recommendations for EC2 instance types based on historical utilization data.

How to eliminate wrong answers

Option A is wrong because AWS Cost Explorer provides cost and usage data visualization and forecasting, but it does not analyze instance utilization metrics or generate specific rightsizing recommendations for EC2 instance types. Option B is wrong because AWS Trusted Advisor offers general best-practice checks, including cost optimization, but its EC2-specific recommendations are limited to idle instances and reserved instance utilization, not detailed rightsizing recommendations based on historical utilization patterns. Option D is wrong because Amazon CloudWatch Dashboard is a monitoring and visualization tool for metrics and logs, but it does not automatically analyze utilization data to produce instance type change recommendations; it requires manual setup and interpretation.

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104
MCQmedium

A company runs a web application on EC2 instances behind an ALB. They want to optimize costs for variable traffic patterns while maintaining high availability. Which solution is MOST cost-effective?

A.Use Dedicated Hosts to run the application and share resources across multiple accounts.
B.Use a mix of On-Demand and Spot Instances in an Auto Scaling group with a target tracking scaling policy.
C.Purchase Reserved Instances for the expected baseline capacity and use On-Demand for spikes.
D.Use only On-Demand EC2 Instances with an Auto Scaling group to handle variable traffic.
AnswerB

Spot Instances provide cost savings for fault-tolerant workloads, and Auto Scaling adjusts capacity dynamically.

Why this answer

Option B is correct because using Spot Instances in an Auto Scaling group with a mix of On-Demand and Spot instances provides cost savings while maintaining availability. Option A is wrong because Reserved Instances require a 1- or 3-year commitment and are not flexible for variable traffic. Option C is wrong because Dedicated Hosts are more expensive and not needed for this use case.

Option D is wrong because On-Demand only is more expensive than using Spot.

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105
MCQeasy

A company runs a web application on EC2 instances behind an Application Load Balancer. The application experiences variable traffic patterns. What is the MOST cost-effective way to ensure the application scales based on demand?

A.Provision a fixed number of EC2 instances that can handle peak load at all times.
B.Use EC2 Auto Scaling with a scheduled scaling policy that adds instances during business hours.
C.Use EC2 Auto Scaling with a target tracking scaling policy based on average CPU utilization.
D.Use EC2 Auto Scaling with a manual scaling plan that requires an administrator to adjust the desired capacity.
AnswerC

Target tracking automatically adjusts capacity to maintain a target metric, scaling cost-effectively.

Why this answer

Option C is correct because a target tracking scaling policy automatically adjusts capacity based on a CloudWatch metric, which is cost-effective compared to manual or scheduled scaling. Option A is wrong because manual scaling is not automated. Option B is wrong because scheduled scaling does not handle variable traffic well.

Option D is wrong because it over-provisions instances.

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106
Multi-Selectmedium

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?

Select 2 answers
A.Purchase Reserved Instances for the baseline capacity.
B.Use Dedicated Hosts for all instances to control placement.
C.Implement Auto Scaling to match capacity with demand.
D.Enable T2/T3 unlimited to handle spikes without throttling.
E.Use multiple instance types in each Availability Zone.
AnswersA, C

Correct: Reserved Instances offer up to 72% discount for steady-state usage.

Why this answer

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.

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107
Multi-Selecthard

Which TWO configurations can improve the performance of an Amazon RDS for PostgreSQL database that is experiencing high read latency? (Choose TWO.)

Select 2 answers
A.Upgrade to a larger instance size.
B.Enable provisioned IOPS on the DB instance.
C.Create a read replica in the same AWS Region.
D.Enable Multi-AZ deployment.
E.Enable storage auto-scaling.
AnswersB, C

Provisioned IOPS provides consistent and low-latency I/O.

Why this answer

Option B is correct because enabling Provisioned IOPS on an Amazon RDS for PostgreSQL database provides consistent and predictable I/O performance, which directly reduces read latency by ensuring sufficient IOPS for read-intensive workloads. Option C is correct because creating a read replica offloads read traffic from the primary DB instance to the replica, reducing contention and improving read latency for the primary instance.

Exam trap

The trap here is that candidates often confuse Multi-AZ deployment with read replicas, mistakenly thinking Multi-AZ improves read performance, when in fact the standby in Multi-AZ is not accessible for reads and only provides failover redundancy.

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108
Multi-Selecthard

An application writes logs to an S3 bucket. The logs are accessed frequently for the first 30 days, then rarely after that, but must be retained for 7 years. Which THREE steps should be taken to optimize cost? (Choose three.)

Select 3 answers
A.Use an S3 Lifecycle policy to transition objects to S3 Glacier Deep Archive after 90 days.
B.Use an S3 Lifecycle policy to transition objects to S3 Standard-IA after 30 days.
C.Delete logs older than 30 days.
D.Set an S3 Lifecycle policy to expire objects after 7 years.
E.Use S3 Intelligent-Tiering to automatically optimize costs.
AnswersA, B, D

Deep Archive is cheapest for long-term archival.

Why this answer

Options A, C, and E are correct. S3 Lifecycle rules can transition objects to lower-cost storage classes. S3 Standard-IA is for infrequent access, and Glacier Deep Archive is for long-term archiving.

Option B is incorrect because Intelligent-Tiering has monitoring costs. Option D is incorrect because deleting logs violates retention requirement.

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109
MCQmedium

A company has a production RDS for PostgreSQL database with a db.r5.large instance. The database experiences high read traffic during business hours. The SysOps administrator needs to improve read performance and ensure high availability at minimal cost. Which solution should the administrator implement?

A.Upgrade the instance to db.r5.xlarge and enable automatic backups.
B.Create a Multi-AZ deployment and then add a Read Replica in a different Availability Zone.
C.Enable Multi-AZ on the existing instance to provide automatic failover but no read scaling.
D.Use Amazon ElastiCache for Redis to cache frequent queries.
AnswerB

Multi-AZ provides failover, Read Replica offloads read traffic, and both improve availability.

Why this answer

The correct answer is A. A Multi-AZ deployment with a Read Replica in another AZ provides both high availability and read scaling. Option B is wrong because increasing instance size is costly and does not provide HA.

Option C is wrong because Multi-AZ alone does not offload read queries. Option D is wrong because ElastiCache adds complexity and cost, and is not directly a database solution.

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110
Multi-Selectmedium

A company is running a production web application on EC2 instances. Which TWO actions would improve both cost efficiency and performance?

Select 2 answers
A.Enable detailed monitoring on all instances.
B.Purchase Reserved Instances for the baseline capacity.
C.Terminate all idle instances.
D.Use larger instance types for all instances.
E.Implement Auto Scaling to adjust capacity based on demand.
AnswersB, E

Reserved Instances reduce cost for steady load.

Why this answer

Option A and D are correct. Auto Scaling adjusts capacity to match demand, reducing cost during low traffic and maintaining performance during peaks. Purchasing Reserved Instances for baseline reduces cost.

Terminating idle instances saves cost but doesn't improve performance. Using larger instances may improve performance but increases cost.

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111
MCQmedium

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?

A.The upload will succeed only if the developer uses HTTP.
B.The upload will fail because the policy denies all s3:* actions.
C.The upload will fail because the policy requires explicit HTTPS.
D.The upload will succeed because the CLI uses HTTPS by default.
AnswerD

Default CLI uses HTTPS, which satisfies the policy condition.

Why this answer

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.

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112
MCQmedium

A company runs an e-commerce application on Amazon EC2 instances behind an Auto Scaling group. The application has a predictable baseline load from 8 AM to 8 PM daily and low load overnight. The SysOps administrator wants to optimize costs while ensuring sufficient capacity for the baseline load. Which purchasing option and scaling strategy should the administrator use?

A.Use On-Demand instances for the baseline and Spot Instances for any additional capacity.
B.Use Reserved Instances for the predicted baseline and On-Demand for any unexpected spikes.
C.Use Dedicated Hosts for all instances to maximize cost savings.
D.Use Spot Instances for all instances to minimize costs.
AnswerB

Reserved Instances offer up to 72% discount for consistent usage. On-Demand covers variable capacity needs, providing a cost-effective and flexible solution.

Why this answer

Option B is correct because Reserved Instances provide a significant discount (up to 72%) over On-Demand for predictable, steady-state workloads like the 8 AM to 8 PM baseline. On-Demand instances then cover any unexpected spikes without requiring upfront commitment, ensuring cost optimization while maintaining capacity for the predictable load.

Exam trap

The trap here is that candidates assume Spot Instances are always the cheapest option, but they fail to recognize that the predictable baseline load requires guaranteed availability, which Spot Instances cannot provide due to potential interruptions.

How to eliminate wrong answers

Option A is wrong because Spot Instances can be interrupted with a 2-minute warning when AWS needs capacity back, making them unsuitable for a baseline load that must be reliably available during business hours. Option C is wrong because Dedicated Hosts are a physical server dedicated to your use, which is far more expensive than Reserved Instances and provides no cost optimization benefit for a standard e-commerce application that does not require license compliance or physical isolation. Option D is wrong because Spot Instances are not suitable for all instances due to their potential for interruption, which would cause the application to fail during the predictable baseline load.

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113
MCQhard

A SysOps administrator notices that a Lambda function is timing out after 30 seconds. The function processes large files from S3. How can the administrator improve performance while minimizing cost?

A.Increase the timeout value to 5 minutes.
B.Enable Provisioned Concurrency.
C.Increase the memory allocation of the Lambda function.
D.Deploy the function on an EC2 instance.
AnswerC

More memory provides more CPU, reducing execution time.

Why this answer

Option A is correct because increasing memory also increases CPU and network, which can speed up processing. Increasing timeout alone won't improve speed. Using a larger instance type is not applicable.

Provisioned Concurrency adds cost.

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114
MCQhard

A company is using AWS Direct Connect to connect its on-premises data center to AWS. The company notices that data transfer costs are increasing. The company wants to reduce data transfer costs without impacting performance. Which action should the company take?

A.Increase the bandwidth of the Direct Connect connection to improve performance.
B.Use Direct Connect gateway to connect to multiple VPCs across regions.
C.Set up a VPN connection over the Direct Connect to encrypt traffic.
D.Use VPC endpoints for S3 and DynamoDB to reduce data transfer costs.
AnswerB

Direct Connect gateway enables connecting to multiple VPCs with a single connection, reducing costs.

Why this answer

Direct Connect gateway allows you to connect to multiple VPCs in different regions using a single Direct Connect connection, reducing the need for multiple connections and thus lowering costs. VPC endpoints reduce data transfer costs for traffic to S3 and DynamoDB but not general data transfer. VPN over Direct Connect adds complexity and does not reduce costs.

Increasing bandwidth would increase costs.

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115
MCQhard

An application runs on EC2 instances behind an ALB. Users report slow response times. CPU utilization averages 90% during peak hours. What is the MOST effective way to improve performance?

A.Enable detailed monitoring on CloudWatch.
B.Switch to a memory-optimized instance type.
C.Add more Security Group rules.
D.Increase the instance size to a larger type.
AnswerD

Larger instances provide more CPU capacity.

Why this answer

Option A is correct because increasing instance size directly addresses high CPU utilization. Auto Scaling handles load changes but may not fix underlying performance. Changing instance type to compute-optimized can help but scaling out is more cost-effective.

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116
MCQmedium

A company runs a batch processing job every night on Amazon EC2 instances. The job takes exactly 2 hours to complete and can be interrupted and resumed later. The SysOps administrator wants to minimize compute costs. Which purchasing option should be used?

A.Spot Instances
B.Reserved Instances
C.On-Demand Instances
D.Dedicated Instances
AnswerA

Spot Instances provide the highest discount and are suitable for flexible, interruptible workloads like batch processing.

Why this answer

Spot Instances are the correct choice because the batch job is fault-tolerant (can be interrupted and resumed) and runs for a fixed 2-hour window nightly. Spot Instances offer up to 90% cost savings compared to On-Demand, and with the ability to handle interruptions via checkpointing, they minimize compute costs without requiring a long-term commitment.

Exam trap

The trap here is that candidates often choose On-Demand Instances due to a mistaken belief that any interruptible workload requires guaranteed availability, ignoring that Spot Instances are explicitly designed for fault-tolerant, stateless, or checkpointable workloads like batch processing.

How to eliminate wrong answers

Option B (Reserved Instances) is wrong because they require a 1- or 3-year commitment and are cost-effective only for steady-state workloads, not for a nightly 2-hour job that can be interrupted. Option C (On-Demand Instances) is wrong because they are the most expensive option and provide no cost savings for a fault-tolerant, interruptible workload. Option D (Dedicated Instances) is wrong because they are designed for regulatory or licensing requirements that demand physical isolation, not for cost optimization, and they incur additional per-instance fees.

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117
MCQmedium

A company runs a batch processing job every night that takes exactly 2 hours to complete. The job is time-sensitive and cannot tolerate interruptions. The SysOps administrator needs to minimize compute costs for the Amazon EC2 instances used during this job. The job runs every day and has predictable resource requirements. Which purchasing option should the administrator choose?

A.Reserved Instances (Standard)
B.Spot Instances
C.On-Demand Instances
D.Dedicated Hosts
AnswerA

Reserved Instances provide a substantial discount for a steady-state workload and guarantee capacity, meeting both cost and reliability requirements.

Why this answer

A Standard Reserved Instance is the best choice because the job runs every night for exactly 2 hours with predictable resource requirements, making it ideal for a 1-year or 3-year commitment that provides a significant discount (up to 72%) over On-Demand pricing. Since the job cannot tolerate interruptions, Reserved Instances offer capacity reservation and cost savings without the risk of termination that Spot Instances carry.

Exam trap

The trap here is that candidates often choose Spot Instances for cost savings without recognizing the 'cannot tolerate interruptions' constraint, or they incorrectly assume Reserved Instances require a full-time workload, when in fact they can be applied to any predictable usage pattern, even a 2-hour daily window.

How to eliminate wrong answers

Option B is wrong because Spot Instances can be interrupted with a 2-minute warning when AWS reclaims capacity, which violates the requirement that the job cannot tolerate interruptions. Option C is wrong because On-Demand Instances are the most expensive option and do not minimize costs for a predictable, recurring workload. Option D is wrong because Dedicated Hosts are used for licensing or compliance requirements (e.g., Windows Server with per-socket licensing) and are significantly more expensive than Reserved Instances, providing no cost benefit for this batch processing job.

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118
MCQhard

A SysOps administrator notices that an S3 bucket's storage costs have increased significantly. The bucket stores log files and is configured with S3 Standard storage class. Most logs are accessed only once after 30 days. Which action will reduce costs without affecting data retrieval?

A.Create a lifecycle policy to transition objects to S3 Standard-IA after 30 days.
B.Create a lifecycle policy to transition objects to S3 Glacier Deep Archive after 30 days.
C.Create a lifecycle policy to transition objects to S3 Glacier Instant Retrieval after 30 days.
D.Create a lifecycle policy to transition objects to S3 One Zone-IA after 30 days.
AnswerC

Glacier Instant Retrieval has lower storage cost and millisecond retrieval for one-time access.

Why this answer

Option C is correct because transitioning to S3 Glacier Instant Retrieval after 30 days reduces storage cost while maintaining millisecond access. Option A is wrong because S3 Standard-IA has retrieval fees that might increase cost for single access. Option B is wrong because S3 One Zone-IA is cheaper but less durable.

Option D is wrong because S3 Glacier Deep Archive has long retrieval times.

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119
Multi-Selectmedium

A company is using Amazon S3 to store data for analytics. The data is accessed frequently for the first 30 days, then rarely after that. The company wants to optimize storage costs. Which THREE actions should the SysOps administrator recommend?

Select 3 answers
A.Use S3 Intelligent-Tiering to automatically optimize storage costs.
B.Use S3 One Zone-IA for all data after 30 days to reduce costs.
C.Create a lifecycle policy to transition objects to S3 Glacier Deep Archive after 90 days.
D.Create a lifecycle policy to transition objects to S3 Standard-IA after 30 days.
E.Use S3 Standard storage for all data to ensure high performance.
AnswersA, C, D

Intelligent-Tiering moves data between tiers based on access patterns.

Why this answer

Option B is correct because S3 Intelligent-Tiering automatically moves data between tiers. Option C is correct because lifecycle policies can transition objects to colder storage. Option E is correct because S3 Glacier Deep Archive is the cheapest for long-term archival.

Option A is wrong because S3 Standard is more expensive than Standard-IA for infrequent access. Option D is wrong because S3 One Zone-IA is for infrequent access but does not provide high availability.

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120
MCQmedium

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?

A.Migrate the database to Amazon Aurora with Auto Scaling enabled.
B.Change the storage type to gp3 and increase IOPS.
C.Upgrade the DB instance to a larger instance type with more vCPUs.
D.Create one or more RDS Read Replicas in the same region and direct read traffic to them.
AnswerD

Read Replicas distribute read load at a low cost.

Why this answer

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.

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121
MCQmedium

A SysOps administrator is troubleshooting slow application performance. The application runs on Amazon EC2 instances in an Auto Scaling group behind an Application Load Balancer. Amazon CloudWatch metrics show that the average CPU utilization across the instances is below 20%, but the application is still slow. What is the MOST likely cause of the performance issue?

A.The Auto Scaling group is scaling too aggressively, causing thrashing.
B.The Application Load Balancer has a sticky session configuration that is not distributing traffic evenly.
C.The application database is under-provisioned and is causing slow query responses.
D.The EC2 instances are using burstable performance and have exhausted their CPU credits.
AnswerC

A database bottleneck can cause slow performance despite low app server CPU.

Why this answer

Option B is correct because if the database is the bottleneck, even if the application servers have low CPU usage, the overall performance can be slow due to database contention. Option A is wrong because if the ALB is not distributing traffic, some instances would have high CPU. Option C is wrong because low CPU utilization indicates that the application servers are not overloaded.

Option D is wrong because burstable performance instances (T-series) have a CPU credit balance; if the balance is depleted, CPU performance is throttled, leading to low CPU but slow performance? Actually, when credits are exhausted, T instances provide baseline performance, which may be low, but CPU utilization would still be limited, not necessarily low; but more importantly, the symptoms match a database bottleneck.

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122
MCQeasy

A company is using AWS Cost Explorer to analyze spending. They want to receive an email alert when costs exceed a certain threshold. Which service should they use?

A.AWS Trusted Advisor
B.AWS Cost Explorer
C.Amazon CloudWatch
D.AWS Budgets
AnswerD

AWS Budgets can send notifications when costs exceed thresholds.

Why this answer

Option D is correct because AWS Budgets can send alerts when costs exceed thresholds. Option A is wrong because Cost Explorer is for analysis, not alerts. Option B is wrong because CloudWatch does not natively monitor AWS costs.

Option C is wrong because Trusted Advisor provides recommendations, not cost alerts.

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123
MCQmedium

A media company stores millions of video files in S3. Some files are accessed heavily after upload (when new) and rarely afterward; others are accessed unpredictably across months. The team cannot predict which files will be accessed and when. They want to minimize storage costs without risking retrieval latency penalties or per-object retrieval fees. Which storage class is appropriate?

A.Use S3 Intelligent-Tiering so objects automatically move between Frequent and Infrequent Access tiers based on access patterns, with no retrieval fees
B.Use S3 Standard-IA and configure a lifecycle policy to move objects back to Standard after every access
C.Use S3 Glacier Instant Retrieval for all objects because it offers the lowest storage cost with millisecond retrieval
D.Use S3 Standard for all objects because it has no retrieval fees and provides the best availability
AnswerA

Intelligent-Tiering handles the unpredictable access pattern automatically. Objects accessed within 30 days stay in Frequent Access. Unaccessed objects move to Infrequent Access (40 percent lower cost). No retrieval fee ensures there is no cost penalty when an old file is accessed unexpectedly. The per-object monitoring fee is offset by storage savings for objects over 128 KB.

Why this answer

S3 Intelligent-Tiering is the correct choice because it automatically moves objects between Frequent Access and Infrequent Access tiers based on changing access patterns, with no retrieval fees and no performance impact (millisecond latency). This matches the unpredictable access pattern described, as the service monitors access at the object level and adjusts storage tier without manual lifecycle rules or retrieval costs.

Exam trap

The trap here is that candidates often confuse S3 Intelligent-Tiering with S3 Standard-IA, assuming both have retrieval fees, or they incorrectly believe Glacier Instant Retrieval is always cheaper despite its retrieval fees and minimum storage duration penalties.

How to eliminate wrong answers

Option B is wrong because S3 Standard-IA charges a per-object retrieval fee (per GB retrieved) and a minimum storage duration fee (30 days), and moving objects back to Standard after every access would incur repeated retrieval fees and lifecycle transition costs, defeating cost minimization. Option C is wrong because S3 Glacier Instant Retrieval has a higher storage cost than Intelligent-Tiering for frequently accessed data and still incurs retrieval fees (per GB) for every access, plus a minimum 90-day storage charge, making it unsuitable for unpredictable access patterns. Option D is wrong because S3 Standard has the highest storage cost among the options, and while it has no retrieval fees, it does not optimize costs for files that become rarely accessed over time, leading to unnecessary expense.

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124
MCQmedium

A company runs a batch processing application on Amazon EC2 instances that runs every night for 2 hours. The job can be interrupted and resumed without any issue. The SysOps administrator wants to minimize compute costs for this workload. Which EC2 purchasing option should be used?

A.Spot Instances
B.On-Demand Instances
C.Reserved Instances
D.Dedicated Hosts
AnswerA

Spot Instances offer the deepest discounts and are suitable for workloads that can be interrupted and resumed.

Why this answer

Spot Instances are the correct choice because the workload is fault-tolerant (can be interrupted and resumed) and runs for only 2 hours nightly. Spot Instances offer significant cost savings (up to 90% off On-Demand) but can be reclaimed by AWS with a 2-minute warning, which is acceptable here since the job can resume without issue. This aligns with the goal of minimizing compute costs for a non-critical, interruptible batch process.

Exam trap

The trap here is that candidates often choose Reserved Instances (Option C) thinking they always save money, but they fail to recognize that Reserved Instances are only cost-effective for steady-state, always-on workloads, not for short, interruptible batch jobs where Spot Instances provide greater savings without long-term commitment.

How to eliminate wrong answers

Option B (On-Demand Instances) is wrong because they provide no cost savings for a fault-tolerant workload that can handle interruptions; On-Demand is priced at the standard rate and is intended for unpredictable or critical workloads, not for minimizing costs. Option C (Reserved Instances) is wrong because they require a 1- or 3-year commitment and are designed for steady-state, predictable usage, not for a 2-hour nightly job that could be interrupted; the upfront cost and commitment would not be cost-effective for such a short, interruptible workload. Option D (Dedicated Hosts) is wrong because they are a physical server dedicated to a single customer, incurring high costs regardless of usage, and are intended for compliance or licensing requirements, not for minimizing compute costs for a batch job.

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125
MCQhard

A company uses Amazon S3 to serve large files to users. The files are accessed frequently for the first 30 days after upload, then access drops significantly. The SysOps administrator wants to minimize storage costs while ensuring low-latency access for frequently accessed files and automatic optimization for changing access patterns. Which S3 storage class configuration should be used?

A.Use S3 Standard for 30 days, then transition to S3 Glacier Deep Archive.
B.Use S3 Intelligent-Tiering.
C.Use S3 Standard then transition to S3 Glacier Flexible Retrieval after 30 days.
D.Use S3 One Zone-IA for the first 30 days, then transition to S3 Standard-IA.
AnswerB

S3 Intelligent-Tiering automatically optimizes costs by moving objects between access tiers based on usage patterns. It provides low-latency access for frequently accessed objects and automatically moves infrequently accessed objects to a lower-cost tier.

Why this answer

S3 Intelligent-Tiering is the correct choice because it automatically moves objects between three access tiers (frequent, infrequent, and archive instant) based on changing access patterns, without any lifecycle rules or performance impact. This meets the requirement for low-latency access for frequently accessed files and automatic optimization, while minimizing storage costs as access drops after 30 days.

Exam trap

The trap here is that candidates often choose a lifecycle-based solution (like S3 Standard to Glacier) thinking it is automatic, but they overlook that lifecycle rules are static and do not adapt to changing access patterns, whereas S3 Intelligent-Tiering dynamically optimizes without manual intervention.

How to eliminate wrong answers

Option A is wrong because S3 Glacier Deep Archive has a retrieval time of 12-48 hours, which does not provide low-latency access for frequently accessed files, and it requires manual lifecycle rules rather than automatic optimization. Option C is wrong because S3 Glacier Flexible Retrieval has retrieval times of minutes to hours (typically 1-5 minutes for expedited, but with additional cost), which does not guarantee low-latency access, and it requires a lifecycle policy rather than automatic pattern adaptation. Option D is wrong because S3 One Zone-IA does not provide the durability of multiple Availability Zones and is not suitable for frequently accessed files due to retrieval costs, and transitioning to S3 Standard-IA after 30 days still requires manual lifecycle rules and does not automatically optimize for changing access patterns.

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126
MCQmedium

The finance team was surprised by a $12,000 spike in EC2 costs last month caused by a runaway Auto Scaling group. They want to receive an email alert within hours whenever any AWS service cost behaves unexpectedly, without manually setting fixed dollar thresholds for each service. Which AWS cost management feature provides this?

A.Enable Cost Anomaly Detection with an AWS services monitor and create an alert subscription to email the finance team when an anomaly is detected
B.Create an AWS Budget with a monthly EC2 cost threshold of $10,000 and an alert at 80 percent of the threshold
C.Enable AWS Cost Explorer and review the daily cost breakdown each morning to spot unexpected charges
D.Configure CloudWatch Billing alarms with a static threshold for each AWS service individually
AnswerA

Cost Anomaly Detection's ML model learns the historical spending pattern for each service. When EC2 (or any service) starts spending at an anomalous rate, the model detects it within hours. The alert subscription can notify via email or SNS with the anomaly amount, affected service, and percentage deviation. No manual threshold tuning is needed — the model self-calibrates.

Why this answer

Cost Anomaly Detection uses machine learning to model historical spending patterns for each AWS service and automatically detects unusual spikes without requiring manual thresholds. By creating an AWS services monitor and linking an alert subscription, the finance team receives email notifications within hours when any service deviates from its expected cost behavior, directly addressing the need for service-agnostic, threshold-free alerts.

Exam trap

The trap here is that candidates often confuse AWS Budgets or CloudWatch Billing alarms with anomaly detection, but those tools require manual static thresholds and do not automatically adapt to changing spending patterns across multiple services.

How to eliminate wrong answers

Option B is wrong because an AWS Budget with a fixed monthly EC2 cost threshold of $10,000 and an 80% alert requires manual threshold setting and only monitors EC2, not all services, and cannot detect unexpected behavior that stays under the threshold. Option C is wrong because manually reviewing AWS Cost Explorer daily is not an automated alerting mechanism and does not provide timely notification within hours of a spike. Option D is wrong because CloudWatch Billing alarms require configuring a static dollar threshold for each individual service, which is exactly what the finance team wants to avoid, and they do not adapt to changing spending patterns.

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127
MCQeasy

A SysOps administrator is responsible for an AWS account that hosts a development environment. The environment includes several EC2 instances that are used only during business hours (9 AM to 5 PM) on weekdays. The administrator wants to reduce costs by stopping the instances during off-hours. Which action should the administrator take to automate this process?

A.Manually stop the instances at 5 PM and start them at 9 AM each weekday.
B.Create an Auto Scaling group with a scheduled scaling action to set desired capacity to 0 during off-hours.
C.Set up a CloudWatch alarm that stops instances when CPU utilization is below 1% for 30 minutes.
D.Use the AWS Instance Scheduler to define a schedule that stops instances at 5 PM and starts them at 9 AM on weekdays.
AnswerD

Correct: Instance Scheduler automates start/stop on a schedule, reducing costs.

Why this answer

Option A is correct because AWS Instance Scheduler is a solution that automatically starts and stops instances based on a schedule. Option B (manual stop) is not automated. Option C (Auto Scaling) does not stop instances, it adds/removes based on demand.

Option D (CloudWatch alarm) can stop instances based on CPU, but not a fixed schedule.

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128
Multi-Selecteasy

A SysOps administrator wants to reduce the cost of storing infrequently accessed data in Amazon S3. The data must be retained for 10 years for compliance. Which TWO actions should the administrator take? (Choose TWO.)

Select 2 answers
A.Use S3 Glacier Deep Archive as the destination for the lifecycle transition.
B.Store the data in S3 Standard.
C.Enable S3 Versioning to protect against accidental deletion.
D.Configure an S3 Lifecycle policy to transition objects to S3 Glacier Deep Archive after 30 days.
E.Use S3 Intelligent-Tiering to automatically optimize costs.
AnswersA, D

Deep Archive is the lowest-cost storage class for long-term retention.

Why this answer

Correct options: B and D. Option B is correct because S3 Lifecycle policies can transition objects to lower-cost storage classes over time. Option D is correct because S3 Glacier Deep Archive is the cheapest storage class for long-term archival.

Option A is wrong because S3 Standard is expensive for infrequent access. Option C is wrong because S3 Intelligent-Tiering has a monitoring cost and is best for unknown access patterns. Option E is wrong because enabling versioning increases storage costs due to multiple versions.

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129
MCQmedium

A company hosts a web application on EC2 instances behind an Application Load Balancer (ALB). The application experiences variable traffic patterns with occasional spikes. The current setup uses On-Demand instances in an Auto Scaling group with a simple scaling policy based on average CPU utilization. The team wants to optimize cost while ensuring that the application can handle spikes in traffic. What should the team do to reduce cost?

A.Switch to a target tracking scaling policy based on request count per target.
B.Implement scheduled scaling to add capacity during known peak hours.
C.Configure the Auto Scaling group to use a mixed instances policy with Spot Instances for a portion of the capacity and On-Demand for the remainder.
D.Purchase Reserved Instances for the minimum expected capacity to get a discount.
AnswerC

Spot Instances can reduce costs significantly while maintaining availability through On-Demand fallback.

Why this answer

Option B is correct because Spot Instances are cost-effective and can be used alongside On-Demand for variable workloads; the Auto Scaling group can use a mixed instances policy to maintain availability while reducing cost. Option A (reserved instances) locks in cost for steady usage but does not help with spikes. Option C (scheduled scaling) is not suitable for unpredictable traffic.

Option D (target tracking) improves scaling but does not directly reduce cost; it uses On-Demand instances which are more expensive.

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130
MCQhard

A SysOps administrator is troubleshooting a cost overrun in an AWS account. The cost explorer shows that data transfer costs have significantly increased. The architecture includes an Application Load Balancer (ALB) internet-facing, EC2 instances in private subnets, and an S3 bucket for static assets. Which action will MOST effectively reduce data transfer costs?

A.Enable Amazon CloudFront to cache static assets and reduce direct requests to the ALB.
B.Implement a VPC Gateway Endpoint for S3 so that traffic from EC2 to S3 stays within the AWS network.
C.Replace the NAT Gateway with a NAT instance to reduce hourly charges.
D.Change the ALB to internal (private) and use AWS Direct Connect for user access.
AnswerB

Gateway endpoints are free and reduce data transfer costs to S3.

Why this answer

The correct answer is D. Data transfer from EC2 to S3 within the same region is free when using a VPC endpoint (gateway endpoint). Option A is wrong because CloudFront reduces latency but does not eliminate data transfer costs from ALB to EC2.

Option B is wrong because moving to private ALB would require a VPN and may increase costs. Option C is wrong because NAT Gateway charges for data processing and transfer.

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131
MCQhard

A company uses Amazon S3 for static website hosting. The website serves thousands of users globally, and the company wants to reduce latency and lower data transfer costs. Which solution should the SysOps administrator implement?

A.Set up Amazon CloudFront as a content delivery network (CDN) in front of the S3 bucket.
B.Use S3 Intelligent-Tiering storage class.
C.Enable cross-region replication and serve from multiple buckets.
D.Enable S3 Transfer Acceleration on the bucket.
AnswerA

CloudFront caches content at edge locations, reducing latency and data transfer costs.

Why this answer

Amazon CloudFront is a global content delivery network (CDN) that caches static content at edge locations closer to users, reducing latency and lowering data transfer costs by minimizing direct requests to the S3 origin. By serving cached objects from edge locations, CloudFront also reduces the amount of data transferred from S3, which can significantly decrease S3 data transfer egress charges.

Exam trap

The trap here is that candidates confuse S3 Transfer Acceleration (which speeds up uploads) with a CDN solution for download performance, or they think cross-region replication alone solves latency without considering the need for a global caching layer.

How to eliminate wrong answers

Option B is wrong because S3 Intelligent-Tiering optimizes storage costs by moving objects between access tiers based on usage patterns, but it does not reduce latency or data transfer costs for global users. Option C is wrong because cross-region replication creates copies in multiple regions, but users still access a single bucket directly unless a routing mechanism like Route 53 latency-based routing is added, and it increases storage costs without providing edge caching benefits. Option D is wrong because S3 Transfer Acceleration uses AWS edge locations to speed up uploads to S3 over long distances, but it does not cache content for downloads or reduce latency for end users retrieving static website content.

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132
MCQmedium

A company runs a mix of Amazon EC2 instances, Amazon RDS databases, and AWS Lambda functions for production workloads. The workloads are steady-state and predictable. The SysOps administrator wants to reduce costs while maintaining flexibility to change instance families and regions. Which pricing model should be recommended?

A.EC2 Instance Savings Plans
B.Compute Savings Plans
C.Standard Reserved Instances
D.Spot Instances
AnswerB

Applies to EC2, Fargate, and Lambda across families and regions.

Why this answer

Compute Savings Plans provide the most flexibility because they automatically apply to EC2 instances, AWS Lambda, and AWS Fargate usage across any instance family, size, or region, as long as the compute spend stays within the committed hourly amount. This matches the requirement to reduce costs on steady-state workloads while retaining the ability to change instance families and regions, unlike EC2 Instance Savings Plans which are limited to a specific instance family in a region.

Exam trap

The trap here is that candidates often confuse Compute Savings Plans with EC2 Instance Savings Plans, assuming both offer the same flexibility, but Compute Savings Plans are the only option that covers Lambda and Fargate while allowing cross-region and cross-family changes.

How to eliminate wrong answers

Option A is wrong because EC2 Instance Savings Plans are restricted to a specific instance family (e.g., m5) within a chosen region, so changing instance families or regions would break the commitment and lose the discount. Option C is wrong because Standard Reserved Instances lock you into a specific instance type, size, and Availability Zone for a 1- or 3-year term, offering no flexibility to change families or regions without incurring modification fees or forfeiting the discount. Option D is wrong because Spot Instances are designed for fault-tolerant, interruptible workloads and are not suitable for steady-state, predictable production workloads due to the risk of termination when capacity is reclaimed.

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133
MCQmedium

A company runs a web application on EC2 instances behind an Application Load Balancer. The application experiences variable traffic patterns. The operations team notices that during low traffic periods, there are still a large number of running instances, leading to higher costs. What should the team do to reduce costs while maintaining performance?

A.Replace the existing instances with larger instance types to handle peak load.
B.Implement a target tracking scaling policy based on average CPU utilization.
C.Manually scale down the number of instances during off-peak hours.
D.Purchase Reserved Instances for the baseline capacity.
AnswerB

Automatically adjusts capacity based on demand, lowering costs during low traffic.

Why this answer

Using a target tracking scaling policy based on average CPU utilization allows the Auto Scaling group to automatically adjust the number of instances based on demand, reducing costs during low traffic. Option A is wrong because manual scaling does not automate cost optimization. Option B is wrong because Reserved Instances do not address variable traffic.

Option D is wrong because increasing instance size may not reduce the number of instances during low traffic.

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134
MCQmedium

A company has multiple AWS accounts and wants to centrally track costs and usage across all accounts. Which AWS service should the SysOps administrator use?

A.AWS Budgets
B.AWS Config
C.AWS Trusted Advisor
D.AWS Organizations
AnswerD

Provides consolidated billing and central cost management.

Why this answer

Option B is correct because AWS Organizations allows you to consolidate billing and get a single bill for all accounts, enabling cost tracking. AWS Budgets and Cost Explorer help analyze costs but require consolidated view. AWS Config tracks configuration, not costs.

Trusted Advisor provides recommendations but not central cost tracking.

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135
MCQhard

A SysOps administrator manages a fleet of 50 EC2 instances running a batch processing application. The instances are launched via an Auto Scaling group with a dynamic scaling policy based on CPU utilization. The company recently switched to a new workload that is memory-intensive, causing frequent scale-out events. The administrator notices that the CPU utilization remains below 40%, but memory usage is consistently above 80%. The scaling policy does not trigger appropriately, leading to performance degradation. The administrator must optimize the solution to respond to memory pressure without incurring unnecessary costs. Which action should the administrator take?

A.Create a custom CloudWatch metric for memory utilization and configure a target tracking scaling policy using that metric.
B.Increase the minimum size of the Auto Scaling group to 10 instances and use manual scaling for peak times.
C.Change the dynamic scaling policy to a step scaling policy based on CPU utilization with a wider cooldown period.
D.Replace the current instance type with a memory-optimized instance type such as r5.large.
AnswerA

Correct: Custom metrics allow Auto Scaling to respond to memory pressure, optimizing performance and cost.

Why this answer

Option C is correct because creating a custom CloudWatch metric for memory utilization and using a target tracking policy allows Auto Scaling to respond to the actual bottleneck. Option A (changing to step scaling with CPU) does not address memory. Option B (manual scaling) is not automated.

Option D (t3.large) is a reactive instance type change, not a scaling solution.

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136
MCQhard

A company uses Amazon CloudFront to distribute content globally. The SysOps administrator notices that the origin load is high and the cache hit ratio is low. What should the administrator do to improve the cache hit ratio and reduce origin load?

A.Change the origin protocol policy to HTTPS only.
B.Add an additional origin server.
C.Enable compression for the content.
D.Increase the minimum, maximum, and default TTL values for the cache behavior.
AnswerD

Longer TTLs improve cache hit ratio.

Why this answer

Option C is correct because increasing the TTL allows objects to be cached for longer, which increases the likelihood of cache hits. Option A is wrong because enabling compression reduces transfer size but does not affect cache hit ratio. Option B is wrong because using a different origin protocol does not change caching behavior.

Option D is wrong because adding more origins does not improve cache hit ratio; it can actually complicate caching.

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137
MCQeasy

A company runs a development Amazon EC2 instance that is only used during business hours (9 AM to 5 PM). The SysOps administrator wants to reduce compute costs. Which action should be taken?

A.Use On-Demand instances
B.Use a Reserved Instance
C.Schedule the instance to automatically stop during off-hours and start before business hours
D.Use a Spot instance
AnswerC

This directly reduces costs by paying only for the hours the instance is running, aligning with the usage pattern.

Why this answer

Option C is correct because the instance is only needed during business hours (9 AM to 5 PM), so automatically stopping it during off-hours and starting it before business hours eliminates compute charges for idle time. Stopped instances incur no EC2 instance running costs (only storage and EBS volume costs), directly reducing the compute bill. AWS Instance Scheduler or a simple cron-based Lambda function can enforce this schedule reliably.

Exam trap

The trap here is that candidates often confuse cost reduction strategies and choose Reserved Instances (Option B) for any recurring workload, failing to recognize that a development instance with limited daily usage does not justify a long-term commitment and that stopping the instance when idle is the most direct way to eliminate compute costs.

How to eliminate wrong answers

Option A is wrong because On-Demand instances are already the default and do not reduce costs; they are the most expensive pricing model for predictable workloads. Option B is wrong because Reserved Instances require a 1- or 3-year commitment and are designed for steady-state, always-on usage, not for a development instance that is only used 8 hours a day. Option D is wrong because Spot instances can be terminated by AWS with only a 2-minute warning, making them unsuitable for a development instance that must be available during business hours without interruption.

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138
MCQhard

A SysOps administrator notices that the monthly bill for Amazon RDS is higher than expected. The environment includes multiple DB instances with low CPU and memory utilization. Which action will most effectively reduce costs while maintaining performance?

A.Enable Multi-AZ deployment for high availability
B.Resize the DB instances to a smaller instance class
C.Delete unused RDS snapshots
D.Provisioned IOPS (io1) storage for better performance
AnswerB

Matches capacity to actual usage, reducing cost.

Why this answer

Option D is correct because Rightsizing instances down to a smaller instance class can reduce costs when utilization is low. Option A may increase costs by adding read replicas. Option B may improve performance but at higher cost.

Option C reduces storage cost but doesn't address compute waste.

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139
MCQhard

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?

A.Replace the NAT Gateway with a smaller NAT Gateway to reduce hourly charges.
B.Use an egress-only Internet Gateway for the private subnets.
C.Implement a VPC Gateway Endpoint for Amazon S3 to keep S3 traffic within AWS.
D.Purchase a Dedicated NAT Gateway in the same region to get lower data processing rates.
AnswerD

Dedicated NAT Gateway offers lower per-GB data processing fees, reducing costs without performance impact.

Why this answer

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.

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140
Multi-Selectmedium

A company wants to optimize costs for its Amazon EC2 instances. Which TWO strategies are effective for reducing costs?

Select 2 answers
A.Use Spot Instances for fault-tolerant workloads.
B.Rightsize instances based on utilization metrics.
C.Increase the provisioned IOPS for EBS volumes.
D.Use EBS General Purpose SSD (gp2) volumes instead of gp3.
E.Use Dedicated Hosts to meet compliance requirements.
AnswersA, B

Spot Instances offer substantial discounts.

Why this answer

Using Spot Instances for fault-tolerant workloads can reduce costs significantly (up to 90%). Rightsizing instances ensures you are not paying for unused capacity. Dedicated Hosts increase costs.

Increasing provisioned IOPS increases costs. Using EBS General Purpose SSD (gp3) is cost-effective but not a primary cost reduction strategy.

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141
MCQeasy

A company runs a mix of Amazon EC2 instances and AWS Fargate tasks that are used for both production and development workloads. The usage is steady and predictable. The SysOps administrator wants to maximize cost savings across both compute services without having to manage specific instances or sizes. Which purchasing option should the administrator recommend?

A.Purchase Compute Savings Plans for a 1-year or 3-year term with a commitment that covers the expected compute spend.
B.Purchase EC2 Instance Savings Plans for the most commonly used instance family and region.
C.Purchase Standard Reserved Instances for the EC2 instances and convert Fargate tasks to use Spot Instances.
D.Use On-Demand instances for both EC2 and Fargate because the administrator does not want to make a commitment.
AnswerA

Compute Savings Plans apply to EC2, Fargate, and Lambda usage, regardless of instance size, family, OS, or region (within the plan's scope). This provides maximum flexibility and significant discounts.

Why this answer

Compute Savings Plans offer the most flexibility, automatically applying to EC2 instances (regardless of instance family, size, or region) and Fargate tasks. Since the company has a mix of both services and wants to maximize savings without managing specific instances or sizes, a 1-year or 3-term Compute Savings Plan with a commitment matching expected spend provides up to 66% savings while covering all compute usage. This aligns with the steady and predictable workload described.

Exam trap

AWS often tests the distinction between Compute Savings Plans and EC2 Instance Savings Plans, where candidates mistakenly choose the latter thinking it covers all EC2 usage, but fail to recognize that Compute Savings Plans also include Fargate and Lambda, making them the only option for a mixed compute environment.

How to eliminate wrong answers

Option B is wrong because EC2 Instance Savings Plans are restricted to a specific instance family within a region, which does not cover Fargate tasks and would not provide the cross-service flexibility needed for the mixed workload. Option C is wrong because Standard Reserved Instances apply only to EC2 instances and require a specific instance family and size commitment, while converting Fargate tasks to Spot Instances introduces interruption risk and does not guarantee cost savings for steady workloads. Option D is wrong because On-Demand pricing offers no discount, and the administrator explicitly wants to maximize cost savings, which requires a commitment-based purchasing option.

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142
Multi-Selectmedium

A company wants to reduce costs for a production Amazon RDS for MySQL DB instance that is running 24/7 but only heavily used during business hours (9 AM to 5 PM). Which TWO actions would be MOST effective in optimizing costs without significantly impacting performance during peak hours?

Select 2 answers
A.Enable Multi-AZ deployment for high availability.
B.Purchase Reserved Instances for the DB instance.
C.Migrate from Provisioned IOPS (io1) storage to General Purpose (gp3) storage.
D.Use AWS Application Auto Scaling to schedule scale-down of the instance size outside business hours.
E.Enable Auto Scaling for the DB instance.
AnswersB, D

Reserved Instances offer a significant discount over On-Demand for steady-state usage.

Why this answer

Option A (Multi-AZ) increases cost and is not needed for cost optimization. Option B (reserved instances) provides a discount for consistent usage. Option C (auto scaling) is not applicable to RDS without additional services like Aurora Auto Scaling.

Option D (scheduled scaling) can reduce instance size during off-peak hours, saving cost. Option E (gp3 storage) can be more cost-effective than provisioned IOPS for many workloads. Correct answers: B and D.

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143
Multi-Selectmedium

A SysOps administrator is optimizing costs for an Amazon RDS for PostgreSQL instance. The database is used for a reporting application that runs only during business hours (9 AM to 5 PM). Which TWO actions should the administrator take to reduce costs? (Choose TWO.)

Select 2 answers
A.Stop the database instance during non-business hours.
B.Move to a larger instance type to handle peaks.
C.Increase the provisioned IOPS for better performance.
D.Purchase a Reserved Instance for the database instance.
E.Configure the database as a Single-AZ deployment instead of Multi-AZ.
AnswersA, E

Stopping the instance eliminates compute charges during off-hours.

Why this answer

Correct options: B and C. Option B is correct because using a Multi-AZ deployment is not necessary if the database can be stopped during off-hours; a Single-AZ deployment reduces costs. Option C is correct because stopping the instance during off-hours saves compute costs.

Option A is wrong because Reserved Instances require a 1 or 3-year commitment and may not be cost-effective if the database is only used part-time; also, the question asks for cost reduction, not commitment. Option D is wrong because increasing instance size increases cost. Option E is wrong because increasing provisioned IOPS increases cost.

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144
Multi-Selecteasy

A SysOps administrator needs to reduce data transfer costs for a web application hosted on EC2 instances in a VPC. The application serves content to users over the internet. Which TWO actions will help reduce data transfer costs? (Choose TWO.)

Select 2 answers
A.Move all instances to private subnets and use AWS Direct Connect for user access.
B.Use a VPC Gateway Endpoint for Amazon S3 to keep S3 traffic within AWS.
C.Use Amazon CloudFront to cache and serve static content.
D.Use an Application Load Balancer to distribute traffic.
E.Use a larger NAT Gateway to improve throughput.
AnswersB, C

Gateway endpoints are free and reduce data transfer costs to S3.

Why this answer

The correct answers are A and B. Amazon CloudFront caches content at edge locations, reducing data transfer from origin to users. Using a VPC Gateway Endpoint for S3 keeps S3 traffic within AWS, avoiding internet data transfer costs.

Option C is wrong because using a larger NAT Gateway increases costs. Option D is wrong because moving to a private subnet and using Direct Connect adds cost. Option E is wrong because using an ALB does not reduce data transfer costs.

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145
Multi-Selecteasy

A company wants to reduce costs for its Amazon S3 storage. Which TWO strategies are effective?

Select 2 answers
A.Enable S3 Object Tagging to categorize data.
B.Enable S3 Replication to another region for disaster recovery.
C.Use S3 Lifecycle policies to transition objects to S3 Glacier Deep Archive after a period.
D.Use S3 Intelligent-Tiering for data with unknown or changing access patterns.
E.Enable S3 Transfer Acceleration for faster uploads.
AnswersC, D

Lifecycle policies reduce storage costs.

Why this answer

S3 Lifecycle policies transition objects to lower-cost storage classes. S3 Object Tagging helps organize data but does not directly reduce costs. S3 Transfer Acceleration increases costs.

S3 Replication increases costs. S3 Intelligent-Tiering can be cost-effective for unknown access patterns.

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146
MCQeasy

A company is running a stateful web application on a single EC2 instance with a 500 GB gp2 EBS volume. The instance is currently at 80% CPU and memory utilization during peak hours. The company wants to improve performance and scalability without incurring high costs. What should the SysOps administrator do?

A.Implement an Application Load Balancer with an Auto Scaling group to distribute traffic across multiple instances.
B.Upgrade the instance to a larger size (vertical scaling).
C.Increase the swap space on the instance to handle memory pressure.
D.Migrate the EBS volume from gp2 to gp3 to improve I/O performance.
AnswerA

Horizontal scaling improves performance and availability while optimizing cost.

Why this answer

The correct answer is B. Using an Application Load Balancer and Auto Scaling group allows the application to scale out based on demand, improving performance and cost efficiency. Option A is wrong because vertical scaling may cause downtime and is limited.

Option C is wrong because converting to gp3 provides performance at lower cost but does not address scalability. Option D is wrong because increasing swap space is a temporary fix and does not improve performance.

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147
MCQeasy

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?

A.AWS Trusted Advisor
B.AWS Budgets
C.AWS Config
D.AWS Cost Explorer with cost allocation tags
AnswerD

Cost Explorer provides detailed cost and usage reports filtered by tags.

Why this answer

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.

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148
MCQhard

A company runs a web application on Amazon EC2 instances in an Auto Scaling group. The application uses Amazon EBS volumes (gp2) for data storage. The SysOps administrator notices that the storage costs are high, and the application's IOPS requirements are consistently below 3000. The administrator wants to reduce storage costs without affecting performance. Which action should the administrator take?

A.Modify the EBS volumes to use Provisioned IOPS (io1) volumes and set IOPS to 2000.
B.Convert the EBS volumes from gp2 to gp3 volume type.
C.Implement an Amazon EBS snapshot lifecycle policy to delete old snapshots and reduce storage costs.
D.Enable EBS optimization on the EC2 instances to improve throughput and reduce costs.
AnswerB

gp3 offers baseline 3000 IOPS and 125 MB/s for a lower price than gp2 for many volume sizes. Since the application requires less than 3000 IOPS, gp3 provides sufficient performance at a reduced cost.

Why this answer

Option B is correct because gp3 volumes offer a baseline performance of 3000 IOPS and 125 MB/s throughput at a lower cost than gp2 volumes, making them ideal for workloads with IOPS requirements consistently below 3000. By converting from gp2 to gp3, the administrator can reduce storage costs without any performance impact, as gp3 provides the same or better baseline performance at a lower price per GB.

Exam trap

The trap here is that candidates may confuse cost reduction strategies for EBS volumes with snapshot management or instance-level optimizations, failing to recognize that gp3 is the direct, cost-effective replacement for gp2 when IOPS requirements are below the gp3 baseline.

How to eliminate wrong answers

Option A is wrong because Provisioned IOPS (io1) volumes are designed for high-performance workloads requiring more than 16,000 IOPS and are significantly more expensive than gp2 or gp3, so using io1 with only 2000 IOPS would increase costs unnecessarily. Option C is wrong because deleting old snapshots reduces snapshot storage costs, not the cost of the EBS volumes themselves, and the question specifically asks about reducing storage costs for the EBS volumes used by the application. Option D is wrong because EBS optimization is a feature that provides dedicated network bandwidth for EBS traffic, improving throughput and reducing latency, but it does not directly reduce storage costs; it may even incur additional costs if the instance type requires it.

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149
MCQeasy

A company runs a batch processing application on Amazon EC2 instances. The application runs for 3 hours every night and can tolerate interruptions. The SysOps administrator needs to minimize compute costs. Which purchasing option should the administrator use?

A.Spot Instances
B.On-Demand Instances
C.Reserved Instances
D.Dedicated Instances
AnswerA

Spot Instances provide large cost savings and are suitable for short-lived, fault-tolerant workloads like batch processing that can be interrupted and resumed.

Why this answer

Spot Instances are ideal for this workload because the application is fault-tolerant (can tolerate interruptions) and runs on a fixed schedule (3 hours nightly). Spot Instances offer significant cost savings (up to 90% compared to On-Demand) by using spare EC2 capacity, and the batch processing can be designed to resume from checkpoints if interrupted.

Exam trap

The trap here is that candidates often choose Reserved Instances for any scheduled workload, failing to recognize that the application's fault tolerance and short nightly duration make Spot Instances the most cost-effective choice despite the risk of interruption.

How to eliminate wrong answers

Option B (On-Demand Instances) is wrong because they are priced at the full rate and do not offer the cost savings needed for a batch workload that can tolerate interruptions. Option C (Reserved Instances) is wrong because they require a 1- or 3-year commitment and are designed for steady-state workloads, not for a 3-hour nightly job that could be run on cheaper Spot capacity. Option D (Dedicated Instances) is wrong because they are the most expensive option, intended for regulatory or licensing requirements, and provide no cost benefit for a fault-tolerant batch application.

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150
MCQhard

A company runs a web application on Amazon EC2 instances behind an Application Load Balancer (ALB). The application reads data from an Amazon RDS for MySQL database. During peak hours, the database CPU utilization is consistently high, and the application experiences increased latency. The SysOps administrator observes that 90% of database queries are read-only. Which combination of actions will both improve performance and optimize costs?

A.Enable Multi-AZ for the RDS instance and scale up the instance size
B.Implement a read replica for the RDS instance and modify the application to route read queries to the read replica
C.Enable Amazon RDS Performance Insights and increase the storage allocation
D.Implement Amazon ElastiCache for Memcached in front of the database and migrate read-heavy queries to cache
AnswerB

Read replicas can handle read traffic, reducing load on the primary instance. This improves performance and, by avoiding unnecessary scale-up, can be more cost-effective. Only the primary instance needs to be sized for writes.

Why this answer

Option B is correct because implementing a read replica offloads read-heavy (90%) queries from the primary RDS instance, reducing CPU utilization and latency. Modifying the application to route read queries to the replica distributes the workload, improving performance while avoiding costly vertical scaling. This optimizes costs by using a smaller primary instance and paying only for the replica's resources.

Exam trap

The trap here is that candidates often confuse Multi-AZ (high availability) with read replicas (performance scaling), or assume caching (ElastiCache) is always the best choice for read-heavy workloads without considering the simplicity and cost-effectiveness of read replicas for database-level offloading.

How to eliminate wrong answers

Option A is wrong because enabling Multi-AZ provides high availability, not performance improvement, and scaling up the instance size increases costs without addressing the read-heavy workload. Option C is wrong because Performance Insights is a monitoring tool that does not reduce CPU utilization or latency, and increasing storage allocation does not improve query performance. Option D is wrong because ElastiCache for Memcached is a caching layer that can reduce database load, but it requires application code changes to cache read queries and does not directly offload read queries like a read replica; it is more suitable for caching specific data, not all read queries.

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